Anatomy and Physiology PDF

ANAPHY REVIEWER ANATOMY - STUDY OF STRUCTURE AND PHYSIOLOGY:TYPES OF STUDY SHAPE - ANATOMY IS DERIVED FROM 1. NEUROPHYSIOLOGY THE GREEK WORDS. - FUNCTIONAL PROPERTIES OF - TO CUT (TOMY), APART (ANA) NERVE CELL PHYSIOLOGY...

ANAPHY REVIEWER ANATOMY - STUDY OF STRUCTURE AND PHYSIOLOGY:TYPES OF STUDY SHAPE - ANATOMY IS DERIVED FROM 1. NEUROPHYSIOLOGY THE GREEK WORDS. - FUNCTIONAL PROPERTIES OF - TO CUT (TOMY), APART (ANA) NERVE CELL PHYSIOLOGY 2. ENDOCRINOLOGY - STUDY OF BODY FUNCTION - HORMONES HOW THEY - PHYSIO (NATURE), OLOGY CONTROL BODY FUNCTIONS (STUDY OF) 3. CARDIOVASCULAR ANATOMY: TYPES OF STUDY PHYSIOLOGY - FUNCTIONS OF THE HEART 1. EMBRYOLOGY AND BLOOD VESSELS - FIRST 8 WEEKS OF DEVELOPMENT 4. IMMUNOLOGY - BODY’S DISEASE AGAINST 2. DEVELOPMENTAL BIOLOGY DISEASE CAUSING AGENT - COMPLETE DEVELOPMENT 5. RESPIRATORY PHYSIOLOGY 3. GROSS ANATOMY - FUNCTIONS OF THE AIR LARGE STRUCTURE; EASILY PASSAGEWAY AND LUNGS OBSERVABLE 6. RENAL PHYSIOLOGY 4. SYSTEMIC ANATOMY - FUNCTIONS OF THE KIDNEY - STRUCTURE OF SPECIFIC SYSTEM IN THE BODY LEVELS OF STRUCTURAL ORGANIZATION 5. REGIONAL ANATOMY - SPECIFIC REGIONS OF THE 1. CHEMICAL LEVEL BODY - ATOMS COMBINE TO FORM MOLECULES. 6. SURFACE ANATOMY - SURFACE MARKINGS OF THE 2. CELLULAR LEVEL BODY TO UNDERSTAND - CELLS ARE MADE UP OF INTERNAL ANATOMY. MOLECULES. 7. MICROSCOPIC ANATOMY 3. TISSUE LEVEL - VERY SMALL STRUCTURE; - CONSIST OF SIMILAR CELLS CAN ONLY BE VIEWED USING - (EPITHELIAL, SMOOTH, AND MICROSCOPE CONNECTIVE TISSUE). 8. CELL BIOLOGY 4. ORGAN LEVEL - CELLULAR STRUCTURE AND - ORGANS ARE MADE UP OF FUNCTION DIFFERENT TYPES OF TISSUES. 9. HISTOLOGY - TISSUES 5. ORGAN SYSTEM LEVEL - TISSUES ARE MADE UP OF - ORGAN SYSTEMS CONSIST CELLS OF DIFFERENT ORGANS THAT WORK CLOSELY TOGETHER  NUTRIENT USE BY BODY 6. ORGANISMAL LEVEL CELLS. - HUMAN ORGANISM ARRE MADE UP OF MANY ORGAN 6. CARDIOVASCULAR SYSTEM SYSTEM. - HEART & BLOOD VESSELS - CARRIES OXYGEN, ORGAN SYSTEM NUTRIENTS, HORMONES, AND OVERVIEW OTHER SUBSTANCES. - WBC AND CHEMICALS IN THE 1. INTEGUMENTARY SYSTEM BLOOD HELP TO PROTECT - SKIN THE BODY FROM SUCH - FORM THE EXTERNAL BODY FOREIGN INVADERS AS COVERING BACTERIA, TOXINS, AND - SYNTHESIZES VITAMIN D TUMOR CELLS. 2. SKELETAL SYSTEM 7. LYMPHATIC SYSTEM - CARTILAGES, JOINT, AND - THORACIC DUCT, LYMPH BONES NODES, LYMPHATIC VESSELS. - PROTECTS AND SUPPORTS - PICKS UP FLUID LEAKED BODY ORGANS FROM BLOOD VESSELS AND - PROVIDES FRAMEWORK THE RETURNS IT TO BLOOD; MUSCLE USE TO CAUSE DISPOSES OF DEBRIS IN THE MOVEMENT LYMPHATIC STREAM; HOUSES - BLOOD CELLS ARE FORMED WBC INVOLVED IN IMMUNITY. WITHIN BONES - STORES MINERALS 8. RESPIRATORY SYSTEM - HEMATOPOIESIS OR - NASAL CAVITY, PHARYNX, FORMATION OF BLOOD LARYNX, TRACHEA, CELLS, TAKES PLACE WITHIN BRONCHUS, LEFT LUNG. THE CAVITIES OF THE - KEEPS THE BLOOD SKELETON. CONSTANTLY SUPPLIED WITH OXYGEN AND REMOVES 3. MUSCULAR SYSTEM CARBON DIOXIDE; THE - MUSCLES GASEOUS EXCHANGES - TO CONTRACT OR SHORTEN OCCUR THROUGH THE WALLS - MACHINES OF THE BODY OF THE AIR SACS OF THE LUNGS. 4. NERVOUS SYSTEM - BRAIN, SENSORY RECEPTOR, 9. DIGESTIVE SYSTEM SPINAL CORD, & NERVES. - ORAL CAVITY, ESOPHAGUS, - FAST ACTING CONTROL STOMACH, SMALL INTESTINE. SYSTEM LARGE INTESTINE, RECTUM, ANUS. 5. ENDOCRINE SYSTEM - BREAKS FOOD DOWN INTO - PINEAL GLAND, PITUITARY ABSORBABLE UNITS THAT GLAND, THYROID GLAND, ENTER THE BLOOD FOR THYMUS GLAND, ADRENAL DISTRIBUTION TO BODY GLANDS, PANCREAS, TESTIS, CELLS; INDIGESTIBLE FOOD OVARY., STUFFS ARE ELIMINATED AS - SECRETE HORMONES THAT FECES. REGULATE PROCESSES SUCH AS GROWTH, REPRODUCTION, AND 10. URINARY 4. DIGESTION SYSTEM/EXCRETORY SYSTEM - Digestion breaks down food into - KIDNEY, URETER, URINARY simple molecules for absorption BLADDER, URETHRA. into the blood, which is - ELIMINATES distributed to all body cells by the NITROGEN-CONTAINING cardiovascular system, a process WASTES FROM THE BODY; performed by the complex human REGULATES WATER, body. ELECTROLYTE, AND - In a simple, one-celled organism ACID-BASE BALANCE OF THE such as an amoeba, the cell itself BLOOD. is the "digestion factory," but in the complex, multicellular human 11. REPRODUCTIVE SYSTEM body, the digestive system - EXISTS PRIMARILY TO performs this function for the PRODUCE OFFSPRING. THE entire body. TESTES OF THE MALE PRODUCE SPERM. OVARIES 5. METABOLISM OF THE FEMALE PRODUCE - The cardiovascular system plays EGGS, OR OVA. a crucial role in the process of metabolism, which involves MAINTAINING LIFE breaking down complex substances into simpler 1. MAINTAINING BOUNDARIES molecules, producing ATP, and - Living organisms maintain distributing oxygen throughout boundaries to separate their the body, regulated by hormones inside and outside. The human from the endocrine system. body is surrounded by an external membrane, 6. EXCRETION integumentary system, and skin, - Excretion removes excreta or protecting internal organs from waste from the body, including drying out, bacteria, and external indigestible food residues in environmental factors like heat feces and nitrogen-containing and sunlight. metabolic wastes in urine, ensuring the body's proper 2. MOVEMENT functioning and functioning. - Movement involves muscular activities like walking and 7. REPRODUCTION manipulating the environment, - The reproductive system, while the skeletal system regulated by hormones from the supports bones. Substances like endocrine system, plays a crucial blood, food, and urine are role in cellular reproduction, the propelled through cardiovascular, process of producing offspring at digestive, and urinary systems. the organismal level, involving the division of original cells to 3. RESPONSIVENESS produce identical daughter cells - Responsiveness involves for body growth or repair. detecting and reacting to environmental stimuli, as seen in 8. GROWTH involuntary hand movements or - Cell-constructing activities occur increased breathing rates in at a faster rate, facilitating response to high levels of carbon growth, which increases the dioxide in the blood. number of cells and is influenced by hormones released by the endocrine system  SURVIVAL NEEDS - it indicates a dynamic state of equilibrium,or a balance 1. NUTRIENTS - absorbed through food, providing HOMEOSTATIC CONTROLS energy and cell building chemicals. Carbohydrates, proteins, and fats fuel cells, while minerals and vitamins support cell reactions and blood oxygen transport. 2. OXYGEN - Oxygen is crucial for nutrient availability and energy release from food. About 20% of air we breathe is oxygen, made available through respiratory and cardiovascular systems. NEGATIVE FEEDBACK MECHANISM 3. WATER - regulate body temperature, heart - Water, the most abundant rate, blood pressure, breathing chemical substance in the body, rate, and blood levels. The makes up 60-80% of body weight thermostat located in a part of and serves as the fluid base for your brain called the body secretions and excretions. hypothalamus, contains both the receptor and control center, 4. APPROPRIATE TEMPERATURE triggering the heating system - Normal body temperature is when the temperature drops crucial for life-sustaining chemical below 200°C. Other negative reactions. Low temperatures slow feedback mechanisms also metabolic reactions, while high regulate other bodily functions. temperatures cause protein breakdown and death. Skeletal POSITIVE FEEDBACK muscle activity generates most - like blood clotting and baby birth, body heat. are rare in the body as they - Normal body temp 37C (98F) increase disturbance and push variables away from their original 5. ATMOSPHERIC PRESSURE value. - the force exerted by air on the body's surface, influences HOMEOSTATIC IMBALANCE breathing and oxygen and carbon - a disturbance in body organs and dioxide exchange in the lungs internal conditions, increases the risk of disease and the HOMEOSTASIS associated changes with aging. - body's ability to maintain relatively stable internal conditions even though the outside world is continuously changing. - homeostasis is "unchanging" (homeo = the same, stasis = standing still)  to an animal's back. Thus, the dorsal surface of four-legged animals is their superior surface. ANTERIOR BODY LANDMARKS abdominal: anterior body trunk inferior to ribs acromial: point of shoulder antebrachial: forearm antecubital: anterior surface of elbow axillary: armpit brachial: arm buccal: cheek area THE LANGUAGE OF ANATOMY carpal: wrist The term caudal, literally "toward cervical: neck region the tail," is synonymous with coxal: hip inferior only to the inferior end of crural: leg the spine. deltoid: curve of shoulder formed Ventral and anterior are by large deltoid muscle synonymous in humans; this is digital: fingers, toes not the case in four-legged femoral: thigh animals. Ventral refers to the fibular: lateral part of leg "belly" of an animal and thus is frontal: forehead the inferior surface of four-legged inguinal: area where thigh meets animals. body trunk; groin Likewise, although the dorsal and mental: chin posterior surfaces are the same nasal: nose area in humans, the term dorsal refers oral: mouth  orbital: eye area a continuation of the brain, is patellar: anterior knee protected by the vertebrae, which pelvic: area overlying the pelvis surround the spinal cavity. anteriorly pubic: genital region VENTRAL BODY CAVITY sternal: breastbone area - much larger than the dorsal tarsal: ankle region cavity. It contains all the thoracic: chest structures within the chest and umbilical: navel abdomen, that is, the visceral organs in those regions. Like the POSTERIOR BODY LANDMARKS dorsal cavity, the ventral body cavity is subdivided. calcaneal: heel of foot cephalic: head 1. THORACIC CAVITY femoral: thigh - The cavity is separated from the gluteal: buttock rest of the ventral cavity by a lumbar: area of back between dome-shaped muscle, the ribs diaphragm(di'ah-fram). The and hips; the loin organs in the thoracic occipital: posterior surface of cavity(lungs, heart, and others) head or base of skull are somewhat protected by the olecranal: posterior surface of rib cage. A central region called elbow the mediastinum separates the popliteal: posterior knee area lungs into right and left cavities in sacral: area between hips the thoracic cavity.The scapular: shoulder blade region mediastinum itself houses the sural: the posterior surface of leg; heart, trachea,and several other the calf visceral organs. vertebral: area of spinal column 2-3. ABDOMINOPELVIC CAVITY BODY PLANES AND SECTIONS - Some prefer to subdivide it into a 1. SAGITTAL SECTION MEDIAN superior abdominal cavity, (MIDSAGITTAL) SECTION containing the stomach, liver, - Right and left parts of the body. intestines,and other organs, and an inferior pelvic cavity,with the 2. FRONTAL (CORONAL) reproductive organs, bladder, and SECTION rectum.However, there is no - Front and back parts of the body. actual physical structure dividing the abdominopelvic cavity. The 3. TRANSVERSE PLANE pelvic cavity is not continuous - Up and down parts of the body. with the abdominal cavity in a straight plane, but rather tips BODY CAVITIES away from the abdominal cavity in the posterior direction. DORSAL BODY CAVITY OTHER BODY CAVITIES 1. CRANIAL CAVITY - Space inside the bony skull. - In addition to the large closed body cavities, there are several 2. SPINAL CAVITY smaller body cavities. Most of - extends from the cranial cavity these are in the head and open to nearly to the end of the vertebral the body exterior. (With the column. The spinal cord, which is exception of the middle ear  cavities, the body regions that house these cavities are all shown in Figure 1.5.) - Oral and digestive cavities. The oral cavity,commonly called the mouth, contains the teeth and tongue. This cavity is part of and continuous with the cavity of the digestive organs,which opens to the exterior at the anus.  CELLS AND TISSUES 3.According to the principle of complementarity, the biochemical activities of cells are dictated by their shape or form and by the relative number of their specific subcellular structures. 4.Continuity of life has a cellular basis. THREE MAIN REGIONS OR PARTS OF A CELL NUCLEUS CYTOPLASM PLASMA MEMBRANE PART 1: CELLS The nucleus is usually located near the CELLS center of the cell. It is surrounded by the - cells are the structural units of all semifluid cytoplasm, which in turn is living things, from one-celled enclosed by the plasma membrane, "generalists" like amoebas to which forms the outer cell boundary. complex multicellular organisms such as humans, dogs, and THE NUCLEUS trees. The human body has 50 to 100 trillion of these tiny building - Headquarters or the control blocks. center. - often oval or spherical, 1600 - DNA, the genetic material, is akin - Robert Hooke was looking to a blueprint with instructions for through a crude microscope at constructing the body. Human some plant tissue cork. He saw DNA differs from frog DNA and some cubelike structures that contains instructions for building reminded him of the long rows of proteins essential for cell monk's rooms(or cells) at the reproduction. A cell without DNA monastery, so he named these is programmed to die if it loses or structures cells. The living cells ejects its nucleus. that had formed the cork were long since dead; only the plant THREE RECOGNIZABLE REGIONS cell walls remained. /STRUCTURE OF NUCLEUS Since the late 1800s, cell research has 1. NUCLEAR been exceptionally fruitful and provided ENVELOPE/MEMBRANE us with four concepts collectively known - Double membrane barrier as the cell theory: - The nuclear envelope contains a fluid-filled space between its two 1. A cell is the basic structural and layers. Fusion points in the functional unit of living organisms.So, envelope create nuclear pores when you define cell properties, you are that allow some substances to in fact defining the properties of life. pass through more easily than other cellular membranes. Inside 2. The activity of an organism depends is nucleoplasm, a jellylike fluid on the collective activities of its cells. that suspends various nuclear do depends on. elements.  2. NUCLEOLI - one or more small, dark-staining, essentially round bodies - Sites where cell structures called ribosomes are assembled. - Ribosomes migrate into the cytoplasm where they serve as the actual sites of protein synthesis. 3. CHROMATIN - When a cell is not dividing, its DNA is combined with protein and forms a loose network of FABRIC OF THE MEMBRANE bumpy threads. - Olive oil-like lipid bilayer. - During cell division, chromatin threads in the nucleus coil and HYDROPHILIC (WATER LOVING) condense to form rod like - Polar heads of the chromosomes, similar to a spring lollipop-shaped phospholipid shortening and thickening when molecules. relaxed. HYDROPHOBIC (WATER HATING) THE PLASMA MEMBRANE - Nonpolar tails - fragile, transparent barrier that - Avoid water and line up in the contains the cell contents and center (interior) of the membrane. separates them from the surrounding environment. GLYCOPROTEINS - The plasma membrane, also - Sugar-proteins known as the cell membrane, defines the cell's boundaries. It is GLYCOCALYX not simply a passive barrier but - Fuzzy, sticky, and sugar-rich area rather a dynamic structure crucial for various cellular functions. Its unique composition enables it to actively participate in numerous activities within the cell. 1. THE FLUID MOSAIC MODEL - The plasma membrane is made up of two lipid layers with proteins floating within. These proteins are free to move and create a dynamic mosaic pattern. The majority of the lipids are phospholipids, some with attached sugar groups, while THREE COMMON TYPE CELL cholesterol is also present in JUNCTIONS: TIGHT JUNCTIONS, substantial amounts. DESMOSOMES, AND GAP JUNCTIONS. 1. Glycoproteins in the glycocalyx act as an adhesive or cellular glue. 2. Wavy contours of the membranes of THREE MAJOR ELEMENTS OF adjacent cells fit together in a CYTOPLASM tongue-and-groove fashion. 1. CYTOSOL 3.Special membrane junctions are - Semi-transparent cytosol fluid formed because this last factor is the suspends nutrients and other most important, let us look more closely solutes, dissolved in a water-rich at the various types of junctions. environment within cells. 1. TIGHT JUNCTIONS 2. ORGANELLES - encircle cells tightly to create - Cell organelles are specialized leak-proof barriers. They fuse metabolic machinery. Each type adjacent plasma membranes like serves a unique function, like a zipper, preventing substances protein synthesis or packaging. from passing between cells. In Together, they work to support the small intestine, they stop the cell's overall activities. digestive enzymes from entering the bloodstream. 3. INCLUSIONS - Cell inclusions, like lipid droplets, 2. DESMOSOMES glycogen granules, pigments, - Anchoring junctions are scattered mucus, and crystals, are stored along cell sides, acting as rivets nutrients or products in cells. to prevent separation under Their presence varies by cell mechanical stress. Structurally, type. Lipid droplets are common they are button-like thickenings of in fat cells, glycogen granules in adjacent plasma membranes liver and muscle cells, and connected by fine protein pigments like melanin in skin and filaments. Thicker filaments hair cells. extend inside cells, forming a strong internal "guy wire" system. CYTOPLASMIC ORGANELLES - specialized cellular 3. GAP JUNCTIONS compartments known as "little - commonly found in the heart and organs" that perform specific between embryonic cells, functions to sustain cell life. Most facilitating communication. They organelles are enclosed by connect neighboring cells through membranes like the plasma hollow protein cylinders called membrane, enabling them to connexons, allowing the direct create unique internal passage of molecules like environments within the cell. This nutrients or ions between cells compartmentalization is essential through water-filled channels. for organelles to carry out their specialized tasks effectively. CYTOPLASM Understanding the operations - cellular material outside the within these cellular "workshops" nucleus and inside the plasma is crucial for comprehending the membrane. functions of our cellular factory - Factory area - Structureless gel MITOCHONDRIA - energy-producing organelles with a double membrane: an outer smooth membrane and an inner membrane with cristae. They break down food with oxygen to produce ATP (Adenosine  triphosphate), which powers transported in vesicles. Rough cellular activities. Cells with high ER is abundant in energy needs, like liver and protein-exporting cells like muscle cells, have many pancreas cells, which produce mitochondria, while less active digestive enzymes. cells have fewer. Lipid-synthesizing enzymes are - Mitochondria are dynamic in found on its external face. shape and function. - They have a double membrane: SMOOTH ER outer (smooth) and inner (with - interacts with the rough ER but cristae). does not participate in protein - ATP is produced through the synthesis. Instead, it is involved breakdown of food with the help in lipid metabolism (cholesterol of enzymes. and fat synthesis and breakdown) - ATP is essential for all cellular and detoxification of drugs and activities. pesticides. It is abundant in liver - Cells with high ATP needs (e.g., cells and cells that produce liver, muscle cells) have many steroid hormones, such as mitochondria; less active cells testosterone-producing cells in have fewer. the male testes. RIBOSOMES - small, bilobed structures composed of proteins and ribosomal RNA. They are the sites of protein synthesis in cells. Some ribosomes are free in the cytoplasm, making proteins for use within the cell, while others are attached to membranes, forming the rough endoplasmic reticulum. ENDOPLASMIC RETICULUM - network of fluid-filled tubules in the cytoplasm, making up about half of a cell's membranes. It acts as a transport system for substances, mainly proteins, within the cell. There are two forms of ER: rough ER, which has ribosomes and is involved in protein synthesis, and smooth ER, which is involved in lipid synthesis. Cells may have one or both types, depending on their functions. ROUGH ER - The rough endoplasmic reticulum (Rough ER) is studded with ribosomes and acts as the cell's membrane factory. It produces and folds proteins, which are then GOLGI APPARATUS electrons that can scramble the - located near the nucleus, structure of proteins and nucleic modifies and packages proteins acids. transported from the rough ER - Free radicals are normal via vesicles. It accumulates by-products of cellular proteins for export, creating metabolism, but if allowed to secretory vesicles for release at accumulate, they can have the plasma membrane. This devastating effects on cells. process is essential for Peroxisomes convert free packaging mucus, digestive radicals to hydrogen peroxide enzymes, proteins, and (H2O2), a function indicated in phospholipids. Additionally, it their naming (peroxisomes generates lysosomes with ="peroxide bodies").The enzyme hydrolytic enzymes for cellular catalase then converts excess use. The Golgi apparatus plays a hydrogen peroxide to water. vital role as a "traffic director" for Peroxisomes are especially cellular proteins, facilitating their numerous in liver and kidney processing and transport to cells,which are very active in various destinations within the detoxification. cell. CYTOSKELETON LYSOSOMES - An internal protein network that - are membrane-bound organelles acts as the cell's "bones and containing digestive enzymes muscles," determining shape, that decompose worn-out supporting organelles, and structures and foreign facilitating intracellular transport substances, playing a vital role in and movement. cellular waste disposal. They vary in size, are abundant in Components: phagocytes for eliminating bacteria, and their enzymes are Microtubules: Tubelike produced by ribosomes and structures that determine cell packaged by the Golgi apparatus. shape and organelle distribution, crucial during cell division. HOMEOSTATIC IMBALANCE - TUBULIN SUBUNITS 25 NM - is ordinarily quite stable,but it Intermediate Filaments: Strong, becomes fragile when the cell is stable, ropelike structures that injured or deprived of oxygen and form desmosomes and provide when excessive amounts of internal support against pulling vitamin A are present. When forces. lysosomes rupture,the cell - FIBROUS SUBUNITS 10NM self-digests. Microfilaments: Involved in cell motility and shape changes, PEROXISOMES including actin and myosin. - are membranous sacs containing - ACTIN SUBUNIT 7NM powerful oxidase enzymes that CENTRIOLES use molecular oxygen(O2) to - Paired, rod-shaped bodies detoxify a number of harmful or located near the nucleus, poisonous substances, including positioned at right angles to each alcohol and formaldehyde. other. - the most important function is to - Structure: Composed of a "disarm" dangerous free radicals. pinwheel array of fine Free radicals are highly reactive microtubules. chemicals with unpaired  - Functions: Generate microtubules and direct the formation of the mitotic spindle during cell division. CELL EXTENSIONS CILIA AND FLAGELLA Cilia: Whiplike extensions that move substances along the cell surface, such as mucus in the respiratory system. Formation: Centrioles multiply and align beneath the plasma membrane, where microtubules sprout to form cilia. Flagella: Longer projections than cilia; the only flagellated cell in the human body is the sperm, which has a single flagellum (tail) for propulsion. MICROVILLI Microvilli: Tiny, fingerlike extensions of the plasma membrane that increase the cell's surface area. Location: Found on cells active in absorption, such as intestinal and kidney tubule cells. Structure: Have a core of actin filaments that extend into the cytoskeleton to stiffen the microvillus. CELL DIVERSITY AND FUNCTION 1.Cells that Connect Body Parts: - Fibroblast: Elongated shape aligns with cable-like fibers it secretes. Has abundant rough ER and Golgi apparatus for protein production. - Erythrocyte (Red Blood Cell): Concave disc shape provides a large surface area for oxygen uptake and streamlined flow through blood. Lacks organelles to maximize oxygen-carrying capacity. 2.Cell that Covers and Lines Body Organs: Epithelial Cell: Hexagonal shape allows tight packing in sheets. Contains intermediate filaments for resistance to tearing.  Membrane Transport: How 3.Cells that Move Organs and Body substances move through plasma Parts: membranes. Protein Synthesis: The process Skeletal and Smooth Muscle Cells: of making proteins. Elongated with abundant contractile Cell Reproduction: How cells filaments to enable movement of bones divide. and internal organs. 1.Diffusion Overview: 4.Cell that Stores Nutrients: - Particles in a solution move continuously and collide with Fat Cell: Large spherical shape due to a each other. large lipid droplet in the cytoplasm. - This movement leads to particles dispersing from areas of higher 5.Cell that Fights Disease: concentration to areas of lower concentration, achieving even Macrophage (phagocytic cells): Extends distribution. pseudopods to move through tissue and - Example: Dye molecules spread engulf pathogens. Contains many in a beaker of water. lysosomes for digesting microorganisms. 2. Understanding Solutions: - A solution is a homogeneous 6. Cell that Gathers Information and mixture of two or more Controls Body Functions: components. - The substance in the largest Nerve Cell (Neuron): Long processes amount is called the solvent (e.g., for receiving and transmitting messages, water in the body). with extensive plasma membrane and - The substances present in rough ER for synthesizing membrane smaller amounts are called components. solutes (e.g., nutrients, salts). 7. Cells of reproduction: 3.Fluid Environments: - Intracellular Fluid: Includes Oocyte (female): The largest cell in the nucleoplasm and cytosol, body,this egg cell contains several containing gasses, nutrients, and copies of all organelles, for distribution salts dissolved in water. to the daughter cells that arise when the - Interstitial Fluid: Surrounds cells, fertilized egg divides to become an containing nutrients, regulatory embryo. substances, salts, and waste products. It’s essential for cells to Sperm (male): This cell is long and extract needed substances and streamlined, built for swimming to the reject waste. egg for fertilization. Its flagellum acts as a motile whip to propel the sperm. 4.Plasma Membrane: - It is selectively permeable, CELL PHYSIOLOGY allowing some substances to pass while excluding others. - Functions of Internal Parts: Each - This selective permeability helps part of a cell has a specific in nutrient intake, waste removal, function, including metabolism, and protection from undesirable digestion, waste disposal, substances. reproduction, growth, movement, and response to stimuli. 5.Homeostatic Imbalance: Osmosis: - In unhealthy or damaged cells, The diffusion of water through a the plasma membrane can selectively permeable membrane. become permeable to nearly Water, though polar and repelled everything, leading to loss of by the lipid core, passes through fluids, proteins, and ions (e.g., in aquaporins (water-specific severe burns). channels). 6.Transport Processes: Facilitated Diffusion: - Passive Processes: No energy Provides passage for substances required from the cell. that are lipid-insoluble and too - Diffusion: Molecules move from large to pass through membrane high to low concentration areas, pores, such as glucose. driven by their kinetic energy. Utilizes protein channels or Speed is affected by molecule carriers to help these substances size and temperature. move down their concentration - Filtration: Occurs across capillary gradients. walls, differing from diffusion. Importance of Diffusion: - Active Processes: Require Essential for transporting water, metabolic energy (ATP) from the glucose, and oxygen into cells cell to drive transport. and removing carbon dioxide. Saves energy for the cell by using passive transport mechanisms. Filtration: The process where water and solutes are pushed through a membrane by hydrostatic pressure. In the kidneys, filtration allows for the removal of water and small solutes from blood into kidney tubules, forming urine. Filtration is not highly selective; it Diffusion in Coffee: mostly retains larger blood cells - Sugar molecules diffuse and proteins. throughout coffee even without stirring, resulting in a sweet taste Active Processes Overview because they become evenly distributed over time. Definition: Active processes use ATP to move substances across Plasma Membrane and Diffusion: the cell membrane when they The hydrophobic core of the cannot pass by diffusion due to plasma membrane acts as a size, lack of specific carriers, lipid barrier to diffusion. solubility, or movement against Simple Diffusion: Molecules concentration gradients. diffuse through the membrane if they are small enough, Active Transport lipid-soluble, or able to pass through membrane pores. Definition: Also known as solute Examples include fats, fat-soluble pumping, active transport uses ATP to vitamins, oxygen, and carbon energize protein carriers (solute pumps) dioxide. to move substances against their Key Points concentration gradients. Active Transport: Uses ATP and Comparison to Facilitated specific protein carriers to move Diffusion: substances against their - Both involve protein carriers. gradients. - Facilitated diffusion relies on the Vesicular Transport: Uses kinetic energy of molecules, while vesicles and ATP to transport active transport relies on ATP. substances without them Examples: crossing the plasma membrane - Sodium-Potassium Pump directly. (Na+-K+ Pump): Moves Na+ out Exocytosis and Endocytosis: of the cell and K+ into the cell. Critical for cellular processes Essential for nerve cell function involving secretion and uptake of and maintaining ion gradients. materials. - Substances: Includes amino acids, some sugars, and ions which are moved against their concentration gradients. Vesicular Transport - Definition: Uses ATP to move substances into or out of cells in vesicles, bypassing direct membrane crossing. Exocytosis: - Function: Moves substances out of the cell, such as hormones, mucus, and cellular wastes. - Process: Substances are Phagocytosis packaged into vesicles by the Definition: A process where Golgi apparatus, which then fuse certain white blood cells and with the plasma membrane to "professional" phagocytes ingest release contents outside the cell. bacteria and foreign debris. Endocytosis: Function: Serves as a protective mechanism rather than a means - Function: Engulfs extracellular of nutrient acquisition. substances by enclosing them in Role: Scavenges and protects vesicles and bringing them into the body by removing harmful the cell. particles and pathogens. - Process: The vesicle formed may fuse with lysosomes for Pinocytosis digestion or travel to the opposite side of the cell for exocytosis. Definition: Also known as "cell drinking," this form of endocytosis Types: involves cells engulfing droplets of extracellular fluid. Phagocytosis: A form of endocytosis Process: The plasma membrane where large particles like bacteria or forms a pit that engulfs fluid dead cells are engulfed by pseudopods containing dissolved substances (cytoplasmic extensions). like proteins and fats. The edges  of the pit then fuse to form a Alternative Term: "Metabolic Phase" vesicle. might be a more accurate description. Significance: A routine activity in most cells, especially important Cell Division: for cells involved in absorption Purpose: Reproduces the cell to (e.g., lining of the small intestine). produce more cells for growth and repair. Receptor-Mediated Endocytosis DNA Replication: Definition: A highly specific form of endocytosis where receptor Timing: Occurs toward the end of proteins on the plasma interphase. membrane bind to specific target molecules. Purpose: Ensures that each daughter Process: Receptor proteins bind cell receives the same genetic material with target molecules, leading to as the original cell. the internalization of both the receptors and the attached Process: The DNA molecules (part of molecules into a vesicle. chromatin) are duplicated exactly to Substances Taken Up: Includes prepare for cell division. enzymes, hormones, cholesterol, iron, and, unfortunately, some Structure of DNA viruses like flu viruses. 1. Components: Selectivity: More selective compared to phagocytosis and Nucleotides: The building blocks of pinocytosis, which are less DNA. specific in their uptake processes. Each Nucleotide Contains: Key Points Deoxyribose Sugar Phagocytosis: Protective and Phosphate Group not nutrient-based; removes Nitrogen-Containing Base (Adenine foreign debris. (A), Thymine (T), Guanine (G), Cytosine Pinocytosis: Routine cell (C)) activity; involved in fluid and solute absorption. 2. Shape: Receptor-Mediated Endocytosis: Highly specific Double Helix: DNA is shaped like a uptake of target molecules, spiral staircase. crucial for acquiring certain nutrients and dealing with Upright Parts: Alternating phosphate pathogens. and sugar units. Cell Life Cycle Rungs: Pairs of nitrogen-containing bases. 1. Phases: DNA Replication Interphase: 1. Initiation: Description: The cell grows and - Uncoiling: The DNA helix performs its usual functions. It is an unwinds and separates into two active phase, not merely a resting nucleotide chains. period between cell divisions.  2. Template Function: copy of the genetic material from - Strand Use: Each separated the parent cell. nucleotide strand acts as a template for the synthesis of a Stages of Mitosis: new complementary strand. 1. Prophase: Chromatin Condensation: Chromatin 3. Complementary Base Pairing: coils and condenses into visible - Adenine (A) Bonds to Thymine chromosomes. (T) - Guanine (G) Bonds to Cytosine Chromosome Structure: Each © chromosome consists of two sister chromatids connected by a centromere. Centriole Movement: Centrioles move 4. Process: to opposite poles of the cell, and the - Continuous: DNA replication mitotic spindle, composed of starts and proceeds until the microtubules, forms between them. entire DNA molecule has been duplicated. Nuclear Envelope Breakdown: The nuclear envelope and nucleoli DNA Replication During disintegrate. Interphase Chromosome Attachment: Overview: Chromosomes attach to spindle fibers at their centromeres. Process Control: DNA replication is controlled by 2. Metaphase: enzymes. Chromosome Alignment: Helix Unwinding: The DNA Chromosomes align along the double helix unwinds and metaphase plate, which is the central separates into two nucleotide plane of the cell. strands. Template Function: Each strand 3. Anaphase: serves as a template for a new complementary strand. Chromatid Separation: The Base Pairing: Adenine (A) pairs centromeres split, and the sister with Thymine (T), and Guanine chromatids (now called chromosomes) (G) pairs with Cytosine (C). For are pulled toward opposite poles of the example, if the template cell. sequence is TACTGC, the complementary new strand will Chromosome Movement: be ATG ACG. Chromosomes move apart, with their Result: Two identical DNA centromeres leading the way. molecules are produced, each 4. Telophase: composed of one original (old) strand and one newly Chromosome Decondensation: synthesized strand. Chromosomes reach the poles and begin to uncoil into chromatin. Events of Cell Division Spindle Disassembly: The mitotic 1. Mitosis: spindle disassembles. Purpose: To ensure that each daughter cell receives an exact Nuclear Envelope Formation: New Higher Solute Concentration: Greater nuclear envelopes form around each set osmotic pressure, causing water to of chromosomes. move into the solution. Nucleoli Reformation: Nucleoli Lower Solute Concentration: Lesser reappear within the new nuclei. osmotic pressure, causing water to move out of the solution. 2. Cytokinesis: 2. Tonicity: Timing: Begins during late anaphase and completes by the Definition: The ability of a solution to end of telophase. change the size and shape of cells by Cytoplasmic Division: A altering the amount of water they contractile ring made of contain. microfilaments forms a cleavage furrow around the middle of the Types of Tonicity: cell. Isotonic: Solutions with the same solute Division Completion: The and water concentrations as the inside cleavage furrow pinches the cell of cells. No net water movement occurs, into two daughter cells, each with so cells retain their normal size and its own nucleus and a portion of shape. the cytoplasm. Hypertonic: Solutions with a higher Additional Details solute concentration than inside cells. Water moves out of the cells, causing Duration of Mitosis: Typically them to shrink. lasts about 2 hours but can vary depending on tissue type. Hypotonic: Solutions with a lower Centriole Replication: Occurs solute concentration than inside cells. during late interphase of the next Water moves into the cells, causing cell cycle, concurrent with DNA them to swell and potentially burst. replication. Cytoplasmic Division Types of IV Solutions Variations: Sometimes the cytoplasm is not divided properly, 1. Isotonic Solutions: leading to binucleate or multinucleate cells, a condition Examples: 0.9% saline (normal saline) common in the liver. and 5% glucose (Dextrose 5% in water). Significance: Uses: Maintain fluid balance. Ensure that red blood cells (RBCs) maintain Normal Function: Mitosis is their normal size and function. essential for growth, development, and tissue repair. Reason for Use: Since isotonic Abnormalities: Uncontrolled solutions match the body's fluid mitosis can lead to tumors and concentration, they don’t disrupt cell cancer. size or shape, making them safe for general hydration and maintenance. Osmotic Pressure and Tonicity 2. Hypertonic Solutions: 1. Osmotic Pressure: Examples: Solutions with higher Definition: The tendency of a solution concentrations of solutes than 0.9% to hold water or "pull" water into it, which saline. is related to the concentration of solutes (dissolved substances) in the solution. Uses: Treat edema by drawing excess In preventing cellular damage, and fluid from tissues into the bloodstream avoiding complications. Each type of for elimination by the kidneys. solution has specific uses based on its tonicity relative to the cells and fluids in Reason for Use: Hypertonic solutions the body. reduce swelling by increasing the osmotic pressure in the blood, causing Protein Synthesis: Overview and water to move from the tissues into the Detailed Process bloodstream. 1. Genes as Blueprints 3. Hypotonic Solutions: Genes: Segments of DNA that Examples: 0.45% saline (half-normal contain the instructions for saline) and distilled water (though building proteins or polypeptides. distilled water is rarely used IV due to Each gene encodes the the risk of cell lysis). sequence of amino acids in a protein. Uses: Rehydrate tissues in cases of Proteins: Vital for cell functions. extreme dehydration. Replace lost fluids They come in two types: when the body has low solute levels. - Fibrous (Structural) Proteins: Reason for Use: Hypotonic solutions Provide structural support to cells have lower osmotic pressure compared and tissues. to cells, causing water to enter cells and - Globular (Functional) Proteins: restore their volume and function. Include enzymes and other molecules that perform various Importance of Proper IV Solution functions essential for cell life. Administration 2. Encoding Information in DNA 1. Preventing Cellular Damage: DNA Structure: DNA is a double Isotonic Solutions: Prevents cells from helix with sequences of swelling or shrinking, maintaining their nitrogenous bases (adenine, function and structure. thymine, cytosine, and guanine). Codons: Sequences of three Hypertonic Solutions: Avoids causing DNA bases (triplets) specify excessive dehydration of cells and particular amino acids. For tissues. example: - AAA codes for phenylalanine. Hypotonic Solutions: Prevents cells - CCT codes for glycine. from bursting due to excessive water Genetic Code: The sequence of intake. codons in DNA determines the sequence of amino acids in 2. Maintaining Fluid Balance: proteins. Different arrangements - Proper IV solution administration of these codons create different ensures that the body's fluid balance is proteins. maintained, preventing complications 3. Role of RNA in Protein Synthesis like dehydration or fluid overload. Differences from DNA: 3. Avoiding Complications: Single-Stranded: RNA is -Incorrect IV solutions can lead to single-stranded, unlike the severe medical issues, including cell double-stranded DNA. lysis (bursting) with hypotonic solutions, Sugar: RNA contains ribose or severe dehydration and electrolyte sugar instead of deoxyribose. imbalances with hypertonic solutions.  Bases: RNA has uracil (U) 2. Elongation: tRNA molecules with instead of thymine (T). complementary anticodons bind to the mRNA codons, bringing Types of RNA: amino acids to the ribosome. The ribosome links the amino acids Messenger RNA (mRNA): together into a polypeptide chain. Carries the genetic instructions 3. Termination: When the ribosome from the DNA in the nucleus to encounters a stop codon on the the ribosomes in the cytoplasm. mRNA, the translation process Transfer RNA (tRNA): Transfers ends, and the newly synthesized amino acids to the ribosome for polypeptide chain is released. protein synthesis. It has a Outcome: A polypeptide (protein) cloverleaf structure and an is synthesized based on the anticodon region that pairs with sequence of codons in the the mRNA codon. mRNA. Ribosomal RNA (rRNA): Combines with proteins to form 5. Summary ribosomes, the sites of protein synthesis. Protein synthesis is a two-step process involving transcription and translation: 4. Phases of Protein Synthesis Transcription: DNA is A. Transcription transcribed to produce mRNA in the nucleus. Process: Translation: mRNA is translated 1. Initiation: RNA polymerase binds into a protein by ribosomes in the to a promoter region on the DNA, cytoplasm, with the help of tRNA unwinding the DNA strands. and rRNA. 2. Elongation: RNA polymerase Proper protein synthesis is essential for reads the DNA template strand cellular functions and maintaining the and synthesizes a body's overall health. Each step must complementary mRNA strand. occur accurately to ensure that proteins 3. Termination: RNA polymerase are synthesized correctly according to reaches a termination signal on the genetic instructions provided by the DNA, and the mRNA strand is DNA. released. 4. Processing: In eukaryotes, the Transcription and Translation: mRNA undergoes processing (capping, polyadenylation, and Detailed Overview splicing) before leaving the 1. Transcription: Converting DNA to nucleus. mRNA Outcome: mRNA carries the genetic code from the DNA in the Transcription is the process by which nucleus to the ribosomes in the the genetic information in DNA is copied cytoplasm. into messenger RNA (mRNA). This process ensures that the information in B. Translation the DNA is conveyed to the ribosomes Process: for protein synthesis. Here’s how transcription works: 1. Initiation: The mRNA attaches to a ribosome. The ribosome scans Initiation: the mRNA until it finds the start - RNA Polymerase Binding: codon (AUG). Transcription begins when RNA polymerase binds to a specific  region on the DNA called the Initiation: promoter. - mRNA Binding: The mRNA - Unwinding of DNA: The DNA strand attaches to a ribosome. double helix unwinds in the The ribosome scans the mRNA region of the gene being until it finds the start codon transcribed. (AUG). Elongation: - First tRNA Binding: The first - RNA Synthesis: RNA tRNA, carrying methionine (the polymerase moves along the amino acid specified by the start DNA template strand, adding codon), binds to the start codon complementary RNA nucleotides on the mRNA. to the growing mRNA strand. For Elongation: example, if the DNA sequence is - Codon Recognition: Each AAT-CGT-TCG, the mRNA subsequent codon on the mRNA sequence produced will be is recognized by a UUA-GCA-AGC. complementary tRNA with an - Base Pairing: Adenine (A) pairs anticodon that matches the with uracil (U) in RNA (instead of mRNA codon. thymine in DNA), and cytosine - Peptide Bond Formation: (C) pairs with guanine (G). Amino acids are linked together Termination: by peptide bonds, forming a - End of Transcription: RNA polypeptide chain. This bond polymerase continues until it formation involves dehydration reaches a termination signal (a synthesis, where a water specific sequence of nucleotides) molecule is removed. on the DNA. - Ribosome Movement: The - Release of mRNA: The mRNA ribosome moves along the strand is released and detaches mRNA, bringing each new codon from the DNA. The DNA strands into the correct position for tRNA rejoin and coil back into a double binding and amino acid addition. helix. Termination: Processing (in eukaryotes): - Stop Codon Recognition: When - Capping: A cap is added to the the ribosome reaches a stop 5' end of the mRNA to protect it codon on the mRNA (UAA, UAG, from degradation and help with or UGA), translation ends. ribosome binding. - Release of Polypeptide: The - Polyadenylation: A tail of completed polypeptide chain is adenine nucleotides is added to released from the ribosome. The the 3' end, which also helps in ribosome dissociates from the stability and export from the mRNA, and the mRNA strand nucleus. can be translated again or - Splicing: Introns (non-coding degraded. regions) are removed, and exons (coding regions) are joined 3. Summary of Key Points together. Transcription: Converts the 2. Translation: Converting mRNA to genetic code in DNA into a Protein complementary mRNA sequence in the nucleus. Translation is the process by which the Translation: Uses the mRNA sequence of nucleotides in mRNA is sequence to assemble amino used to synthesize proteins. It takes acids into a polypeptide chain at place in the cytoplasm and involves the ribosome in the cytoplasm. ribosomes, mRNA, tRNA, and rRNA. Role of RNA Types: The steps of translation are:  mRNA: Carries the genetic code Complexity: These labels from the DNA to the ribosome. simplify the diverse functions tRNA: Transfers amino acids to each tissue performs. the ribosome and matches them Organ Formation: to the mRNA codons. Organs: Tissues are organized rRNA: Forms part of the into organs (e.g., heart, kidneys, ribosome and catalyzes the lungs). formation of peptide bonds Function and Structure: Each between amino acids. organ contains multiple tissue types, and their arrangement BODY TISSUES determines the organ's structure and function. Cell Specialization: Study: Understanding tissues is - Start: The human body begins as crucial for comprehending organ a single fertilized egg cell. function and the overall workings - Division and Specialization: of the body. This single cell divides repeatedly, resulting in millions of EPITHELIAL TISSUE specialized cells. Each type of cell performs specific functions, Definition and Meaning: such as muscle cells, lens cells of Epithelium (Epithelial Tissue): the eye, and skin cells. The term comes from the Greek - Division of Labor: Specialized words "epithelium," where cells work together to benefit the "epithe" means "laid on" or entire organism. "covering," and "thelium" means "a layer" or "a surface." So, epithelium refers to tissue that covers surfaces and lines cavities Risks of Specialization: in the body. - Hazards: Loss or dysfunction of Function: Epithelial tissue serves a small group of specialized cells as the lining, covering, and can severely impact or even glandular tissue of the body. destroy the body. For instance, the heart relies on specialized Types of Epithelial Tissue: cells to control its contractions. Damage to these cells can lead ○ Glandular Epithelium: to heart failure and overall body Forms various glands harm due to lack of oxygen. (e.g., sweat glands, digestive enzymes). Primary Tissue Types: ○ Covering and Lining Epithelium: Covers body Epithelium: Covers surfaces and surfaces and lines internal forms protective layers. cavities. It includes: Connective Tissue: Provides ○ Epidermis: The outer support and structure. layer of the skin. Nervous Tissue: Controls and ○ Lining Epithelium: Lines communicates information. body cavities and organs Muscle Tissue: Facilitates (e.g., respiratory tract, movement. digestive tract). Function Labels: Functions: ○ Protection: Shields Epithelium: Covering against damage (e.g., skin Connective: Support protects from bacteria and Muscle: Movement chemicals). Nervous: Control  Absorption: Absorbs nutrients Squamous: Flattened, scale-like (e.g., in the stomach and small cells. intestine). Cuboidal: Cube-shaped cells. Filtration: Filters substances Columnar: Column-shaped cells. (e.g., in the kidneys). Stratified Epithelium Naming: Secretion: Produces various Named according to the shape of substances (e.g., sweat, oils, the cells at the free (apical) digestive enzymes). surface, not those on the basement membrane. Characteristics: Simple Epithelia: Cell Arrangement: Cells fit closely together to form ○ Functions: Primarily continuous sheets, held together involved in absorption, by specialized junctions like secretion, and filtration. desmosomes and tight junctions. They are typically thin and Surface Features: not suited for protection. Apical Surface: The free surface exposed to the exterior or an Types of Simple Epithelium: internal cavity. Surface Modifications: Includes SIMPLE SQUAMOUS EPITHELIUM: smooth surfaces, microvilli (for - Structure: A single layer of thin, absorption), or cilia (for flat cells resting on a basement movement of debris). membrane. Basement Membrane: A - Arrangement: Cells are closely structureless layer that supports packed, like floor tiles. the epithelial cells, secreted by - Functions: Ideal for rapid both epithelial and underlying diffusion and filtration. Found in connective tissue cells. areas where substances are Avascularity: Epithelial tissues exchanged quickly. do not have their own blood supply; they rely on diffusion from Locations: underlying connective tissues for nutrients and oxygen. Air Sacs of the Lungs (Alveoli): Regeneration: Epithelial cells Facilitates gas exchange (oxygen and regenerate quickly if they are carbon dioxide). well-nourished. Walls of Capillaries: Allows the exchange of nutrients and gasses between blood and tissue cells. 1. Classification of Epithelium: Serous Membranes (Serosae): Lines Naming Conventions: body cavities and covers organs, providing a smooth, lubricating surface. Layers: The first part of the name indicates the number of cell layers: Simple Cuboidal Epithelium: Simple Epithelium: One layer of Structure: Single layer of cells. cube-shaped cells resting on a Stratified Epithelium: More than basement membrane. one cell layer. Locations: ○ Glands and Ducts: Cell Shape: The second part of the Common in glands such name describes the shape of the cells: as salivary glands and pancreas.  ○ Kidney Tubules: Forms Stratified Epithelia: the walls of the tubules. ○ Surface of Ovaries: Structure: Consist of two or Covers the surface. more cell layers. Functions: Primarily involved in Function: Primarily provides secretion and absorption. protection due to its durability. Characteristics: More resistant Simple Columnar Epithelium: to wear and tear compared to simple epithelia. Structure: Single layer of tall, closely packed cells. Stratified Squamous Epithelium: Special Features: ○ Goblet Cells: Often Structure: Composed of multiple present, producing layers of cells. The cells at the lubricating mucus. free surface are flattened Locations: (squamous), while those closer to ○ Digestive Tract: Lines the the basement membrane are entire length from the cuboidal or columnar. stomach to the anus. Function: Provides protection ○ Mucosae (Mucous against abrasion and friction. Membranes): Line body Locations: cavities open to the Esophagus: Protects against the exterior. friction from swallowed food. Functions: Absorption and Mouth: Lines the oral cavity. secretion. The mucus produced Outer Skin (Epidermis): Acts as helps in lubricating and protecting a barrier to protect underlying the digestive tract. tissues. Characteristics: The outer Pseudostratified Columnar layers can be keratinized (e.g., Epithelium: skin) or non-keratinized (e.g., mouth, esophagus). Structure: Appears stratified due to varying cell heights and nuclei Stratified Cuboidal Epithelium: positions, but all cells rest on the basement membrane. Structure: Typically has two Types: layers of cells. The surface cells ○ Non-ciliated: Found in are cuboidal. parts of the male Locations: Found in the ducts of reproductive system. large glands, such as sweat ○ Ciliated: More commonly glands and mammary glands. known as pseudostratified Function: Provides protection ciliated columnar and is involved in secretion. epithelium. Stratified Columnar Epithelium: Locations: ○ Respiratory Tract: Lines Structure: Has multiple layers, most of the respiratory with the surface cells being tract. columnar and basal cells varying Functions: in shape. ○ Ciliated Variety: Mucus Locations: Rare in the body, traps dust and debris; cilia mainly in the ducts of some large move mucus upward and glands. away from the lungs. Function: Provides protection and some secretion. Transitional Epithelium: local effects or are involved in digestion and other functions. Structure: A modified stratified squamous epithelium designed to CONNECTIVE TISSUE stretch. Basal cells are cuboidal or columnar, while surface cells Connective Tissue Overview vary in shape from rounded and dome-like when relaxed to Function: Connective tissue flattened and squamous-like connects, supports, and binds when stretched. together different body tissues. It Locations: is the most abundant and widely ○ Urinary Bladder: Allows distributed tissue type in the for expansion and body. contraction as the bladder fills and empties. Common Characteristics of ○ Ureters: Conducts urine Connective Tissue from the kidneys to the bladder. Variations in Blood Supply: ○ Part of Urethra: Part of Well Vascularized: Most the urinary tract. connective tissues have a good Function: Allows for stretching blood supply. and accommodates fluctuating Poorly Vascularized: Tendons volumes of fluid. and ligaments have limited blood Glandular Epithelium: supply, leading to slow healing. Avascular: Cartilage lacks blood Definition: Composed of cells vessels, which also results in specialized in producing and slow healing. secreting substances. Secretion: The process involves Extracellular Matrix: obtaining materials from the ○ Definition: The extracellular blood to produce a secretion, matrix is the nonliving substance which is then discharged. outside the cells in connective Types: tissue. It consists of: Ground Substance: A Endocrine Glands: structureless material made of water, adhesion proteins, and Structure: Ductless; secretions charged polysaccharide (hormones) are released directly molecules. into the bloodstream. Fibers: Various types of fibers Examples: Thyroid gland, embedded in the ground adrenal glands, pituitary gland. substance, produced and secreted by connective tissue Exocrine Glands: cells. Structure: Have ducts; secretions are transported Extracellular Matrix Components through ducts to the epithelial Ground Substance: surface. Examples: Sweat glands, oil Composition: Water, adhesion proteins, glands, liver, pancreas. and polysaccharide molecules. Function: Exocrine glands can be both internal and external, Function: secreting substances that have  Adhesion proteins act as glue, Bone: helping cells attach to the matrix. ○ Types: Compact bone and Polysaccharides trap water, spongy bone. affecting the consistency of the Blood: matrix (fluid, gel-like, or firm). ○ Characteristics: A connective tissue with a Fibers: fluid matrix (plasma) and cells (red blood cells, white Collagen Fibers: blood cells, and platelets). a. Characteristics: White fibers with high tensile Types of Connective Tissue strength, providing structural support. - Connective tissues are Elastic Fibers: characterized by their cells, the a. Characteristics: Yellow type and amount of fibers, and fibers that can stretch and the nature of their extracellular recoil, allowing tissues to matrix. They can be categorized return to their original into bone, cartilage, dense shape. connective tissue, loose Reticular Fibers: connective tissue, and blood. a. Characteristics: Fine Here's a detailed classification: collagen fibers forming the internal "skeleton" of soft 1. Bone (Osseous Tissue) organs like the spleen. Cells: Osteocytes (bone cells) Functional Variations situated in lacunae (small pits within the matrix). Soft Packing Tissue: Matrix: Composed of a very hard ○ Example: Fat tissue, matrix with calcium salts and a which has a soft matrix high concentration of collagen and is composed mostly of fibers. cells. Function: Provides exceptional Firm and Strong Tissue: support and protection for body ○ Examples: Bone and organs. For example, the skull cartilage, which have few protects the brain. cells but a dense, hard 2. Cartilage matrix, making them extremely strong. Cells: Chondrocytes (cartilage cells). Summary of Connective Tissue Matrix: Less hard than bone, Types: more flexible, with various types: Hyaline Cartilage: The most Connective Tissue Proper: widespread type, with a rubbery ○ Loose Connective matrix and abundant collagen Tissue: Includes areolar, fibers. It supports structures like adipose, and reticular the larynx, rib attachments to the tissues. breastbone, and bone ends. It is ○ Dense Connective prevalent in fetal skeletons but is Tissue: Includes dense mostly replaced by bone after regular, dense irregular, birth. However, growth plates in and elastic tissues. long bones remain as hyaline Cartilage: cartilage. ○ Types: Hyaline cartilage, Fibrocartilage: Highly elastic cartilage, and compressible, forming the fibrocartilage.  cushion-like disks between Adipose Tissue: Known as fat vertebrae in the spinal column. It tissue, it is primarily composed of has a dense network of collagen adipocytes (fat cells) with a large fibers. oil droplet. It stores energy, Elastic Cartilage: Contains insulates the body, and cushions elastic fibers for flexibility, found organs. It forms subcutaneous in structures like the external ear. tissue beneath the skin and around some organs. 3. Dense Connective Tissue Reticular Tissue: Contains a network of reticular fibers and Cells: Fibroblasts (fiber-forming reticular cells. It forms the internal cells). framework (stroma) of organs Matrix: Dense with collagen such as lymph nodes, spleen, fibers. and bone marrow, supporting Types: many free blood cells. Dense Regular Connective 5. Blood Tissue: Collagen fibers are Cells: Red blood cells, white closely packed and aligned blood cells, and platelets. parallel, forming tendons Matrix: Fluid, known as plasma, (muscle-to-bone) and ligaments with soluble proteins that become (bone-to-bone). It is strong and visible during clotting. resists stretching. Function: Transports nutrients, Dense Irregular Connective gasses, wastes, and other Tissue: Collagen fibers are substances throughout the body. arranged irregularly, found in the It serves as a transport vehicle dermis of the skin and joint for the cardiovascular system. capsules. It provides strength and support in multiple directions. Summary Elastic Connective Tissue: Contains abundant elastic fibers Bone: Rigid, protective, and that allow stretching and supportive. recoiling, found in large arteries Cartilage: Flexible, supports and and bronchial tubes. cushions structures, including hyaline, fibrocartilage, and elastic 4. Loose Connective Tissue types. Characteristics: Softer, more Dense Connective Tissue: flexible, with a higher number of Strong and supportive, including cells and fewer fibers compared dense regular and irregular, and to dense connective tissue. elastic types. Loose Connective Tissue: Types: Softer and more flexible, including areolar, adipose, and Areolar Tissue: Soft, pliable reticular tissues. tissue that wraps and cushions Blood: Fluid connective tissue organs. It helps to hold internal involved in transport and immune organs in place and serves as a response. universal packing material. It contains a fluid matrix with Muscle Tissue various fibers and acts as a reservoir for nutrients and waste. Muscle tissue is specialized for It can become swollen due to contraction and is responsible for excess fluid (edema) during movement in the body. There are three inflammation. main types of muscle tissue, each with compared to skeletal and cardiac distinct structures and functions: muscle. 1. Skeletal Muscle Nervous Tissue Location: Attached to the skeleton. - Nervous tissue is involved in receiving and conducting Control: Voluntary (conscious control). electrical impulses throughout the body. It consists of two main Appearance: Long, cylindrical cells with components: multiple nuclei (multinucleate) and obvious striations (stripes). 1. Neurons Function: Moves bones and skin, - Function: Conduct facilitating gross body movements and electrochemical impulses from facial expressions. Cells are also known one part of the body to another. as muscle fibers due to their elongated - Structure: Neurons have a shape. unique structure with long 2. Cardiac Muscle processes (axons and dendrites) that extend over long distances, Location: Found only in the heart. allowing for the transmission of signals. They are characterized Control: Involuntary (not consciously by irritability (ability to respond to controlled). stimuli) and conductivity (ability to transmit impulses). Appearance: Short, branched cells with one nucleus (uninucleate) per cell and striations. Cells fit tightly together at intercalated discs, which contain gap 2. Neuroglia junctions for electrical impulse - Function: Support, insulate, and conduction. protect neurons. They are crucial for the maintenance and function Function: Pumps blood through the of the nervous system. heart and into the blood vessels. The intercalated discs allow for synchronized Types: Includes various supporting cells contractions and rapid conduction of such as astrocytes, oligodendrocytes, impulses across the heart. and Schwann cells, which assist in maintaining the environment around 3. Smooth Muscle neurons and facilitating signal transmission. Location: Walls of hollow organs such as the stomach, uterus, and blood Tissue Repair vessels. When tissue injury occurs, the body Control: Involuntary. initiates a healing process involving two main mechanisms: Appearance: Spindle-shaped cells with a single nucleus and no visible striations. 1. Regeneration Function: Controls movements within ○ Description: Replacement organs by constricting and dilating their of destroyed tissue with cavities, aiding in processes like the same type of cells. peristalsis (wave-like motion that ○ Outcome: Restores the propels food through the digestive tract). original tissue structure Smooth muscle contracts more slowly and function. Epithelial  tissues and most fibrous Skeletal Muscle: Regenerates connective tissues poorly. regenerate well. Cardiac Muscle and Nervous