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Tuesday, August 25, 2020 Science Human Anatomy and Physiology CELL Basic organizational unit of all living things All cells have: cell membrane, cytoplasm (= cytosol), and DNA Cell membrane = comparable to semi-permeable plastic bag Composed of phosph...

Tuesday, August 25, 2020 Science Human Anatomy and Physiology CELL Basic organizational unit of all living things All cells have: cell membrane, cytoplasm (= cytosol), and DNA Cell membrane = comparable to semi-permeable plastic bag Composed of phospholipids Transport holes Organelles: groups of complex molecules that helps a cell survive The larger the cell, the more organ less needed CELL STRUCTURAL ORGANIZATION ALL cells have DNA and RNA and can synthesize proteins Each cell consists of nucleic acids, cytoplasm, and a cell membrane Specialized organelles include mitochondria, and chloroplasts in which they have specific functions within a cell A single cell begins by being asexual or sexual reproduction Cells -> tissues; tissues -> organs; organs -> systems** Organism = complete individual NUCLEAR PARTS OF A CELL Nucleus: contains chromosomes and regulates DNA; defining structure of eukaryotic cells (all eukaryotic cells have nucleus) Responsible for passing on genetic traits Contains nuclear envelope, nucleoplasm, nucleolus, nuclear pores, chromatic, and ribosomes Chromosomes: highly condensed, threadlike rods of DNA 1  Tuesday, August 25, 2020 DNA = deoxyribonucleic acid; stores information about plant or animal Chromatin: consist of DNA and protein that make up chromosomes Nucleolus: contained within the nucleus consists of protein Involved in protein synthesis Synthesizes and stores RNA (= ribonucleic acid) Nucleic envelope: consist of inner and outer membranes made of lipids Nuclear pores: involved in exchange of material between nucleus and cytoplasm Nucleoplasm: similar to cytoplasm CELL MEMBRANES Aka plasma membrane; thin semipermeable membrane of lipids and proteins Consist of phospholipid bilayer with hydrophilic ends of the outer layer facing the external environment; inner layer facing inside of the cell, and hydrophobic ends facing each other Cholesterol in the cell membrane adds stiffness and flexibility Glycolipids help the cell recognize other cells Proteins gives the cell shape Selective Permeability Cell membrane has this with regard to size, charge, and solubility With size, the cell membrane allows only small molecules to diffuse through it Oxygen and water molecules are small and pass through The charge of the ions on cell’s surface either attracts or repels ions Ions with similar charges = repel Ions with opposite charges = attract Molecules that are soluble in phospholipids can usually pass through Those molecules that cannot diffuses must be moved through by active transport and vesicles CELL STRUCTURE 2  Tuesday, August 25, 2020 Ribosomes: synthesize proteins from amino acids Some cells contain thousands of ribosomes, some are mobile, and some are embedded in the Rough endoplasmic reticulum Golgi complex (apparatus): synthesize materials such as proteins that are transported out of cell Consist of layers of membranes Vacuoles: sacs used for storage, digestion, and waste removal Vesicle: small organelle; moves material within a cell Cytoskeleton: consist of microtubules that shape and support the cell Microtubules: part of cytoskeleton and help support the cell; made of proteins Cytosol: liquid material Cytoplasm: aka cytosol, found within plasma membrane Cell membrane: acts as a barrier Helps keep cytoplasms in and substances located outside the cell out Determines what is allowed to enter and exit Endoplasmic reticulum: rough ER (ribosome on surface) and smooth ER (no ribosome on surface) Tubular network that comprises the transport system of a cell Mitochondrion: generates ATP; involved in cell growth and death Contains own DNA Mitochondria Functions Cell energy Cell signaling = communications are carried within a cell Cell differentiation = process whereby a non-differentiated cell becomes transformed into a cell with a more specialized purpose** Cell cycle and growth regulation = process whereby the cell gets ready to reproduce and reproduces 3  Tuesday, August 25, 2020 Consist of inner and outer membrane Inner encloses matrix, which contains the mitochondrial DNA and ribosomes Folds (cristae) = chemical reactions that releases energy and control water levels, and recycle and create proteins and fats Aerobic respiration occurs here Animal Cell Structure Centrosome: comprised of the pair of centrioles Involved in mitosis and cell cycle Centrioles: cylinder-shaped; involved in cellular division Each cylinder consists of nine groups of three microtubules Occur in pairs Lysosome: digest proteins, lipids, and carbohydrates, and also transports undigested substance to the cell membrane to be removed Cilia: appendages expanding from the surface of the cell, the movement of which causes the cell to move Flagella: tail-like structures on cells; help the cell move CELL CYCLE Process by which a cell reproduces, which involves cell growth, the duplication of genetic material, and cell division The entire cell cycle in animal cells can take 24 hrs The two ways that cells can reproduce are through meiosis and mitosis In mitosis, the daughter cell is an exact replica of the parent cell In meiosis, the daughter cell have different genetic coding than the parent cell It only happens in specialized reproductive cells called gametes Meiosis and mitosis occur in humans, animals, and plants; mitosis = asexually** CELL DIFFERENTIATION 4  Tuesday, August 25, 2020 Process that helps determine the cell type for each cell Less-specialized cell becomes a more-specialized cell in a process called zygote** MITOSIS Interphase: cell prepares for division by replacing its genetics and cytoplasmic material Prophase: chromatin thickens intro chromosomes and nuclear membrane begins to disintegrate Metaphase: spindle moves to the center Anaphase: sister chromosomes pull apart then become daughter chromosomes** Telophase: spindle disintegrates, nuclear membranes reform, chromosomes revert to chromatin Cytokinesis: physical splitting of the cell into two cells MEIOSIS Same phase as mitosis but it happens twice First phase: interphase, metaphase, anaphase, telophase, and cytokinesis Chromosomes cross over, genetic material is exchanged, and tetrads are formed Each cell goes through a second cell division which includes: prophase, metaphase, anaphase, telophase, and cytokinesis The result = four daughter cells with different sets of chromosomes Daughters = haploid 5  Tuesday, August 25, 2020 (half of genetic material of parent cell) TISSUES Group of cells that work together Muscle tissue, nerve tissue, epithelial, and connective tissue** (4 tissues total in the body) Categories of Tissues Epithelial: joined together tightly—skin Cell layer and cell shape help classify epithelial tissue** Connective: dense, loose, or fatty; protects and binds body parts — bone tissue, cartilage, tendons, ligaments, fat, blood, and lymph** Cortical bone = connective tissue** Cartilage: cushions and provide structural support; jelly-like and fibrous Pads for vertebrae** Blood: transports oxygen to cells and removes wastes; carries hormones and fights off disease Bone: hard tissue that supports and protects softer tissues and organs; marrow produces rbc Muscle: help support and move the body smooth, cardiac, and skeletal Nervous: located in the brain, spinal cord, and nerves; some send signals to muscles and glands to trigger responses ORGANS Groups of tissues that work together THREE PRIMARY BODY PLANES 1. Transverse: divides the body into superior and inferior (caudal) halves 2. Sagittal: divides body vertically into right and left sections** 3. Coronal: divides the body vertically into anterior and posterior 6  Tuesday, August 25, 2020 Medial: near to the midline Lateral: further away from the body Proximal: closer to center** (closer to trunk) Distal: further away from the center (distal = distance = away) Anterior: front** (A = front of the alphabet) Posterior: back Cephalic: head Cranial: skull Caudad: towards the tail RESPIRATORY SYSTEM Structure Upper respiratory system includes: nose, nasal cavity, mouth, pharynx, and larynx Lower respiratory system: trachea, lungs, and bronchial tree Airway: nose, nasal cavity, mouth, pharynx, larynx, trachea, bronchi, and bronchial network Lined with cilia that trap microbes and debris Lungs: structures that house the bronchi and bronchial network, which extend into the lungs and terminate in millions of alveoli Walls of alveoli allows the exchange of gases with blood capillaries** Alveoli = gas exchange** Right lungs = three lobes** Surrounded by pleural membrane to reduce friction when breathing 7  Tuesday, August 25, 2020 Respiratory muscle includes the diaphragm and intercostal muscles Functions Main function = supply the body with oxygen and get rid of carbon dioxide Delivers oxygen and expels carbon dioxide** Filters air Responsible for speech As air passes through the throat, it moves through the larynx, which vibrates and produces sound, before it enters the trachea Functions in the sense of smell Chemoreceptors that are located in the nasal cavity respond to airborne chemicals Helps the body maintain acid-base homeostasis Hyperventilation = increase in blood pH during acidosis (low pH) Slowing breathing during alkalosis (higher pH) helps to lower blood pH Breathing Process Diaphragm and intercostal muscle contract to expand lungs during creating During inspiration (inhaling): Diaphragm contracts and moves down** Intercostal muscles contract and ribs expands, which increases the size of chest cavity and the pressure decreases During expiration (exhaling): Diaphragm and intercostal muscle relaxes Chest cavity size decreases forcing air out Breathing process is controlled by medulla oblongata 8  Tuesday, August 25, 2020 Monitors the level of carbon dioxide in the blood and signals breathing rate CARDIOVASCULAR SYSTEM Responsible for the internal transport of substances to and from the cells Consist of three parts: Blood: composed of water, solutes, and other elements in a fluid connective tissue Blood vessels: tubules of different sizes that transport blood Heart: muscular pump providing the pressure necessary to keep blood flowing Can be either open or closed Most animals have closed systems, where the heart and blood vessels are continually connected The flow of blood in the capillary beds, the small tubules, is quite slow Lymph vascular system cleans up excess fluids and proteins and returns them to the circulatory system Blood Helps maintain a healthy internal environment in animals by carrying raw material to cells and removing waste products Helps stabilize internal pH and contains infection fighters Blood is composed of red and white blood cells, platelets, and plasma Plasma make up over half of the blood volume Mostly water and serves as a solvent Rbc transports oxygen to cells Form in the bone marrow Can live up to four months Wbc defend the body against infection Lymphocytes, neutrophils, monocytes, eosinophils, and basophils Platelets are fragments of stem cells and serve an important function in blood clotting 9  Tuesday, August 25, 2020 Heart Made up of cardiac muscle tissue Four chambers Each half contains both an atrium and a ventricle LV = muscular** Halves are separated by a valve— AV valve Valves keep blood moving in a single direction and prevent any backwash into the chambers Functions by contracting and relaxing Atrial contraction fills the ventricles and ventricular contraction empties them Known as cardiac cycle Veins = low bp because oxygen poor blood** **Cardiac Cycle** Consist of diastole and systole phases First diastole phase: blood flows through the superior and inferior vena cava Because the heart is relaxed, blood flows passively from the atrium through the open Atrioventricular valve (tricuspid valve) to the right ventricle (tricuspid valve allows deoxygenated blood from RA to RV)** The SA node, the cardiac pacemaker** located in the wall of the right atrium, generates electrical signal, which are carried by the Purkinje fibers to the rest of the atrium, stimulating it to contract and fill the right ventricle with blood When tricuspid valve closes, pulmonary semilunar valve opens 10  Tuesday, August 25, 2020 Blood then gets pumped out the pulmonary arteries to the lungs Blood returning from the lungs fills the left atrium SA node triggers the mitral valve to open, and blood fills the left ventricle SA Node = natural pacemaker** During the second systole phase, the mitral valve closes and the aortic semilunar valve opens The left ventricle contracts, and blood is pumped out of the aorta to the rest of the body Types of Circulation Circulatory system included coronary circulation, pulmonary circulation, and system circulation Coronary circulation is the flow of blood to the heart tissue Blood enters the coronary arteries supplying major arteries, which enters the heart with oxygenated blood Deoxygenated blood return to the right atrium through cardiac veins, which empty into the coronary sinus Pulmonary circulation = heart and lungs Deoxygenated blood flows from RV to lungs through pulmonary arteries** Pulmonary arteries = carries oxygen-depleted blood** Oxygenated blood flows back to the LA through pulmonary veins Pulmonary veins carry oxygen from lungs** Systemic circulation = flow of blood to the entire body with the exception of coronary circulation and pulmonary circulation Blood exits the LV through aorta Portal circulation is included which is the flow of blood from the digestive system to the liver and then to the heart Renal circulation = the flow of blood between the heart and the kidneys Renal circulation = flow of blood between the heart and the kidneys Blood Pressure Fluid pressure generated by the cardiac cycle Arterial bp: transporting oxygen-poor blood into the lungs and oxygen rick blood to the blood tissues 11  Tuesday, August 25, 2020 Capillary beds: diffusion sites for exchanges between blood and interstitial fluids Consist a single layer of endothelial cells Capillaries merge into venules then turn into veins where it transports blood from body tissues back to the heart Lymphatic System Return excess tissue fluid to the bloodstream Consists of lymph capillaries, lymph vessels, and lymph ducts Major function: Return of excess fluid to blood Return of protein from the capillaries Transport of fats from the digestive tract Disposal of debris and cellular waste Lymphoid organs include: lymph nodes, spleen, appendix, adenoids, thymus, tonsils, and small patches of small intestine Lymph nodes contain lymphocytes and plasma cells (secretes antibodies)** Spleen filters blood stores of rbc and macrophages** Thymus secretes hormones Spleen Made up of lymphoid tissue Blood vessels connected to the spleen by splenic sinuses Main function - filter unwanted materials from the blood and help fight infections** GASTROINTESTINAL SYSTEM Function by the following: Movement: mixes and passes nutrients through the system and eliminates waste Secretion: enzymes, hormones, and other substances necessary for digestion are secreted into the digestive tract Digestion: chemical breakdown that enters the internal environment 12  Tuesday, August 25, 2020 Absorption: passage of nutrients through plasma membranes into the blood or lymph and then to the body Mouth and Stomach Digestion begins in the mouth with chewing and mixing nutrients with saliva Salivary glands -> secrete saliva Saliva has enzymes that breakdown start Bolus then move through pharynx and esophagus Stomach main function: Mixing and storing food Dissolving and degrading food via secretions Controlling passage of food into the small intestine Protein digestion begins in stomach Acid helps break down food and make nutrients available for absorption Absorption begins in small intestine Liver Largest solid organ and gland Made up of four lobes right, left, quadrate, and caudate lobes Secured my five ligaments called falciform Coronary, right triangular, left triangular, and round ligaments Nutrient-rich blood is supplied to the liver via hepatic portal vein Hepatic artery supplies oxygen-rich blood Bloods leaves through hepatic veins Blood enters the lobules through portal veins and hepatic artery 13  Tuesday, August 25, 2020 Blood flows through sinusoids Responsible for: Production of bile Blood plasma proteins Cholesterol Storage of excess glucose in the form of glycogen Regulation of amino acids Processing hemoglobin (to store iron) Conversion of ammonia to urea Purification of the blood (drugs) Regulation of blood clotting Controlling infections by boosting immune factors Small Intestine Most nutrients get absorbed here Enzymes from pancreas, liver, and stomach act on fats, carbohydrates, nucleic acids, and proteins Bile is the secretion of the liver and is particularly useful when breaking down fats Bile is stored in the the gallbladder Microvilli is the reason why the SI serves as the main absorption organ Large Intestine Aka colon, concentrates, mixes, and stores waste material Nervous system triggers an impulse in the body to expel the waste from rectum Sphincter is stimulated to expel waste matter Water reabsorption** Pancreas Made up of exocrine and endocrine tissues Exocrine tissue secretes digestive enzyme The endocrine tissue secretes hormones (insulin) into the bloodstream Blood is supplied to the pancreas from the splenic artery, gastroduodenal artery, and the superior mesenteric artery 14  Tuesday, August 25, 2020 Digestive role: Assists in the digestion by secreting enzymes that help breakdown fats and proteins Zymogens are produced by acini Secretes large amounts of sodium bicarbonate to neutralize the stomach acid that reaches the small intestine Exocrine functions are controlled by hormones released by the stomach and duodenum when food is present Exocrine secretion flow into Wirsung’s duct and are delivered to the duodenum NERVOUS SYSTEM Senses, interprets, and issues commands as a response to conditions in the body’s environment It is possible due to neurons Messages are sent through action potential Through chemical synapse, a substance is released that stimulates or inhibits the action of the adjoining cell Functional Types of Neurons Three general functional types: Sensory, motor, and interneurons Sensory neurons: transmit signals to the CNS from the sensory receptors associated with touch, pain, temp., hearing, sight, smell, and taste Motor neurons: transmit signals from the CNS to the rest of the body such as by signaling muscles or glands to respond Interneurons: transmit signals between neurons Neurons consist of three basic parts: cell body, the axon, and motor neurons Dendrites receive impulses and transmit them to the cell body Body contains nucleus of the neuron Axon transmit impulses away from the body CNS 15  Tuesday, August 25, 2020 Two components: Spinal cord: encases in bony structure of vertebrae, which protects and supports it Limb movement and internal activity Brain: hindbrain, midbrain, and forebrain Hindbrain: medulla, cerebellum, and pons Midbrain: integrates sensory signals and orchestrates responses Forebrain: cerebrum (interprets sensory info)**, thalamus, and hypothalamus Cerebral cortex covers the cerebrum Frontal lobe: front; responsible for short term and working memory and information processing as well as decision-making, planning, and judgement Parietal lobe: responsible for sensory input as well as spatial positioning of the body Occipital lobe: visual input, processing, and output Temporal lobe: auditory input, processing, and output Cerebellum: processing and storing implicit memories Classical conditioning learning techniques Informations from the body is sent to the brain through brain stem, and information from the brain is sent through the brain stem Important part of respiratory, digestive, and circulatory functions Midbrain is important part of vision and hearing Medulla oblongata is important when it comes to the autonomous NS in the circulatory and respiratory system Peripheral NS = fight or flight response (sympathetic nerves); control basic body function or rest and digest (parasympathetic nerves)** Autonomous NS Maintains homeostasis Controls the functions of the internal organs, blood vessels, smooth muscle tissues, and glands Accomplished through hypothalamus 16  Tuesday, August 25, 2020 Consist of sympathetic nervous system = fight or flight; and parasympathetic nervous system = rest and digest Involuntary Somatic Nervous System and Reflex Arc SNS controls the five senses and the voluntary movement of skeletal muscle** Somatic nervous system controls skeletal muscle voluntary control** Efferent (motor) and afferent (sensory) nerves help operate the senses and the movement Efferent: bring signals from the CNS to the sensory organs and muscles Afferent: bring signals from the sensory organs and the muscles to the CNS Reflex = automatic response without a thought via reflex arc Reflex arc is the simplest nerve pathway, which bypasses the brain and controlled by the spinal cord MUSCULAR SYSTEM Three types: skeletal, cardiac, and smooth 600 muscles in the body All have three properties: Excitably: all have an electric gradient Contraction: have the ability to contract or shorten Elongate: all muscle tissues share the capacity to elongate or relax Types of Muscular Tissue 1. Skeletal: voluntary muscles Composed of muscle fibers that are in parallel bundles Skeletal muscles are aka striated muscle 2. Smooth: involuntary muscles Found in the walls of internal organs (stomach, intestines, and blood vessels) and sphincters or valves 17  Tuesday, August 25, 2020 Aka as visceral tissues is non striated Cells are shorter and wider 3. Cardiac: involuntary muscles HEART only Striated Skeletal Muscle Contraction Muscle fiber contains a bundle of myofibrils, which are composed of sarcomeres Myofibrils contain two microfilaments Thick: composed of myosin Thin: composed of actin Skeletal muscle attraction occurs when the thin filaments slide over the thick filaments, shorten sarcomere Calcium ions = released when actions potential reaches muscle fiber They bind to myosin and actin which helps in the binding of myosin heads (thick) to the actin molecule (thin) Adenosine triphosphate (ATP) = released from glucoses providing energy for contraction REPRODUCTIVE SYSTEM Male Reproductive System Functions include to produce, maintain, and transfer sperm and semen into the female reproductive tract and to produce male hormones External structure: penis, scrotum, and testes Penis: contains the urethra, can fill with blood and become erect, enabling semen and sperm into female reproductive tract during sexual intercourse Scrotum: sac of skin and smooth muscle that surrounds testes and keeps it at a proper temp. For spermatogenesis Testes: male gonads, which produces sperm and testosterone 18  Tuesday, August 25, 2020 Internal structure: epididymis, vas deferens, ejaculatory ducts, urethra, seminal vesicles, prostate gland, and bulbourethral glands Epididymis: stores sperm Vas deferens: sperm travels through this once it matures to the ejaculatory duct Seminal vesicles: secrete alkaline fluids with proteins and mucus into ejaculatory duct Prostate gland: secretes a milky white fluid with proteins and enzymes as part of semen Bulbourethral gland: secrete fluid into the urethra to neutralize the acidity in the urethra Hormones associated with male reproductive system include: Follicle stimulating hormone (FSH): stimulates spermatogenesis Luteinizing hormone (LH): stimulates testosterone production Testosterone: responsible for male sex characteristics Female Reproductive System Functions include to produce ova (oocytes, or egg cells), transfer ova to fallopian tubes for fertilization, and receive sperm, and to provide a protective, nourishing environment for the developing embryo External structure: labia major, labia minora, Bartholin’s glands and clotirs Labia majora and labia minora: enclose and protect the vagina Bartholin’s glands: secrete a lubricating fluid** Clitoris: contains erectile tissue and nerve endings for sensual pleasure Internal structure: ovaries, fallopian tubes, uterus, and vagina Ovaries: female gonads that produce ova and secrete estrogen and progesterone Fallopian tubes: carry the mature egg toward uterus, where it gets implanted in the uterine 19  Tuesday, August 25, 2020 wall Uterus: protects and nourishes the developing embryo until birth Vagina: muscular tube that extends from the cervix; receives seems and the sperm during sexual intercourse and provides birth canal INTEGUMENTARY SYSTEM Consists of the skin including the sebaceous glands, sweat glands, hair, and nails* Functions includes protection, secretion, and communication Protection: the system protects the body from pathogens including bacteria, viruses, and chemicals Secretion: sebaceous glands secretes sebum that waterproofs skin, and sweat glands are associated with the body’s homeostatic relationship of thermoregulation. It also severs as excretory organs and help get rid of the body of metabolic wastes Communication: sensory receptors are distributed throughout the skin to send information like pain, touch, pressure, and temp. Skin manufactures vitamin D Layers of the Skin Epidermis and dermis and subcutaneous layer below dermis Epidermis: superficial layer** (outer layer) Epithelial cells NO blood vessels** Stratum basale = deepest layer, which is a single layer of cells Keratin: waxy protein that helps waterproof skin Dermis: under epidermis Connective tissue Contains blood vessels, sensory receptors, hair follicles, sebaceous glands, and sweat glands 20  Tuesday, August 25, 2020 Contains elastin and collagen fibers Sebaceous gland = not a layer, aka as hypodermis Connective tissue Help to cushion and insulate body 3 layers** Skin’s Involvement in Temperature Homeostasis Involved in homeostasis through activation of the sweat glands** By thermoregulation, body maintains a stable temperature The temperature is controlled by a negative feedback consisting of a receptor, control center, and effector Receptors: located in the dermis Control center: hypothalamus (brain) Effectors: sweat gland, blood vessels, and muscles (shivering) Evaporation of sweat cools down body Vasodilation of blood vessels also releases heat into the environment to lower body temp. Sebaceous Glands vs. Sweat Glands Both exocrine glands found in skin Exocrine glands secrete substances into ducts Sebaceous glands = holocrine glands; secretes sebum Sebum is and oily mixture of lipids and proteins Connected to hair follicles and secrete sebum Sebum inhibits water loss from skin and protects against bacterial and fungal infections Sweat glands = eccrine or apocrine glands Eccrine glands: activated by elevated body temp.** located throughout the body and can be found on forehead, neck, and back Secrete electrolytes and water containing sodium chloride, potassium, bicarbonate, glucose, and antimicrobial peptides 21  Tuesday, August 25, 2020 Apocrine glands: secrete an oily solution containing fatty acids, triglycerides, and proteins Located on armpits, groin, palms, and soles of the feet Secrete oily sweat when a person experiences stress or anxiety Body odor = bacteria feeding on apocrine sweat (BACK and LEGS HAS THE LOWEST CONCENTRATION OF SWEAT GLANDS in the body)** ENDOCRINE SYSTEM Responsible for secreting hormones Works with nervous system Hypothalamus and pituitary gland coordinate to serve as neuroendocrine control center** Hormone is triggered by hormonal signals, chemical reactions, and environmental cues Steroid hormones trigger gene activation and protein synthesis Insulin work quickly when body needs it **Eight major glands:** 1. Adrenal cortex: maintain blood sugar level; lipid and protein metabolism 2. Adrenal medulla: cardiac function; raises blood sugar and controls the size of blood vessels 3. Thyroid gland: regulate metabolism and functions in growth and development 4. Parathyroid: regulates calcium levels in blood** 5. Pancreas islets: raises and lowers blood sugar; active in carb metabolism 6. Thymus gland: immune responses 7. Pineal gland: influence on daily biorhythms and sexual activity Melatonin** 8. Pituitary gland: role in growth and development Controlled by hypothalamus (stimulate gonads)** 22  Tuesday, August 25, 2020 Endocrine Functions of the Pancreas Located amongst the grouping of exocrine cells are groups of endocrine cells Islets of Langerhans are made up of insulin-producing beta cells and glucagon- releasing alpha cells Major hormones includes insulin and glucagon Insulin controls carb metabolism by lowering the amount of glucose in the blood Affects fat metabolism and can change liver’s ability to release stored fat Glucagon is used to increase glucose levels Thyroid and Parathyroid Glands Located in the neck below the larynx neck** Thyroid gland: regulate metabolism Secretes thyroxine, triiodothyronine, and calcitonin Thyroxine and triiodothyronine increases metabolism, and calcitonin decreases blood calcium by storing calcium in bone tissue Increase in thyroxine increases heart rate** Hypothalamus: triggers pituitary gland to secrete TSH, which stimulates thyroid gland to release hormones via negative-feedback Parathyroid gland: secrete PTH to increase blood calcium URINARY SYSTEM Consist of kidneys, urinary ducts, and bladder Kidneys Consist of renal cortex, renal medulla, and renal pelvis Renal cortex: approx. one million nephrons; filters of the kidneys Nephron contains glomerulus which is surrounded by Bowman’s 23  Tuesday, August 25, 2020 capsule Renal arteries: where blood is received from Kidney filters blood, reabsorb materials and secrete wastes and excess water in urine Urea and drugs are removed from blood in the distal convoluted tubule Unabsorbed material flows from collecting tubes in renal medulla to the renal pelvis as urine IMMUNE SYSTEM Protects the body against invading pathogens such as bacteria, viruses, fungi, and protists Includes the lymphatic system as well as the red bone marrow and leukocytes (wbc) Tissue fluid enters the lymph capillaries, which combine to form lymph vessels Lymphatic tissues: tonsils, adenoids, thymus, spleen, and Peyer’s patches Tonsils: protect against pathogens entering the body through most and throat Thymus: maturation for immature T cells that forms in the bone marrow Spleen: cleans the blood of dead cells and pathogens Peyer’s patches: protect the digestive system from pathogens Immune defenses include: Skin: barrier against bacteria Ciliated Mucous Membranes: cilia sweep pathogens out of the respiratory tract** Glandular secretions: secretions from exocrine glands destroy bacteria Gastric secretions: gastric acid destroys pathogens Normal bacterial populations: compete with pathogens in the gut and vagina Phagocytes and inflammation responses mobilize wbc and chemical reactions to stop infection Plasma protein act as complement system to repel bacteria and pathogens Three types wbc: 24  Tuesday, August 25, 2020 1. Macrophages: phagocytes that alert T cells to the presence of foreign substance 2. T lymphocytes: attack viruses and bacteria 3. B lymphocytes: target specific bacteria for destruction Memory cells, suppressor T cells, and help T cells contributes to body’s defense Types of Leukocytes Produced in red bone marrow Classified as monocytes, granulocytes, T lymphocytes, B lymphocytes, or natural killer cells Macrophages: largest, long living phagocytes that engulf and destroy pathogens Dendritic cells: present antigens to T cells Neutrophils: short-living phagocytes that respond quickly to invaders Basophils: alert body for invasions Eosinophil: large, long-living phagocytes that defend against multicellular invaders T lymphocytes include helper T cells, killer T cells, suppressor T cells, and memory T cells Helper T cell: help the body fight infections by producing antibodies Killer: destroy cells that are infected with a virus or pathogen and tumor cells Suppressor: stop or suppress the other T cells when battle is over Memory: remain in blood on alert B lymphocytes = produce antibodies Antigen and Typical Immune Response Stimulate the immune system Body attacks cells if they have unfamiliar antigens Antibodies bind on antigens on the surface of pathogens and mark them for destruction by other phagocytes Antigen stimulates antibody production Active and Passive immunity At birth, innate immune system protects an individual from pathogens Adaptive immunity is developed when someone encounters infection or immunization, which reacts to pathogens 25  Tuesday, August 25, 2020 Phagocytes stimulate adaptive immunity** Naturally acquired active immunity: exposed and builds immunity to a pathogen WITHOUT AN IMMUNIZATION Artificially acquired active immunity: individual is exposed and builds immunity BY A VACCINE Naturally acquired passive immunity: during pregnancy as antibodies MOVE FROM MOTHER TO FETUS Artificially acquired passive immunity: IMMUNIZATION given in recent outbreaks; quick and short-lived protection SKELETAL SYSTEM Contains both bones and cartilage Divided into: Axial skeleton: skull, sternum, ribs, and vertebral column (spine) Appendicular skeleton: arms, feet, hands, legs, hips, and shoulders Axial Skeleton and the Appendicular Skeleton Consist of 206 bones Axial skeleton: 80 bones; vertebral column, rib cage, sternum, skull, and hyoid bone Vertebral column: 33 vertebrae; cervical, thoracic, lumbar, and sacral vertebrae Rib cage: 12 paired ribs; 10 true pairs and 2 pars of floating Sternum: manubrium, corpus sterni, xiphoid process Skull: cranium and facial bones Hyoid bone: attachement point for the tongue muscles = protects vital organs (brain, heart, and lungs) Appendicular skeleton: 126 bones; pectoral girdle, pelvic girdle, and appendages Pectoral: scapulae and clavicles pelvic: two pelvic bones Upper appendages: arms; humerus, radius, ulna, carpals, metacarpals, and phalanges 26  Tuesday, August 25, 2020 Lower appendages: legs; femur, patella, fibula, tibia, tarsal, metatarsals, and phalanges Sesamoid bones are embedded into tendons** Functions Structural support, providing movement, providing protection, producing blood cells, and storing substances such as fat and minerals Red marrow manufactures red and white bc Yellow bone marrow stores fat Provides a reservoir to store minerals calcium and phosphorus Important role: Movement: action of skeletal muscles on bones move the body Mineral storage: serve as storage facilities for essential mineral ions Support: act as a framework and support system for the organs Blood Cell Information: rbc are produced in the marrow of certain bones Bones are classified as long, short, flat, or irregular Synovial joints = freely moveable Compact and Spongy Bone Compact bone: tightly packed cells, strong, dense, and rigid Haversian system provides reservoir for calcium and phosphorus for the blood Spongy bone: consist of trabeculae; network girders with open spaces filled with red bone marrow Lightweight and porous 27  Tuesday, August 25, 2020 Life and Physical Sciences MACROMOLECULES Large and complex molecules; important in cell structure and function Four basic macros: 1. Carbohydrates 2. Nucleic acids 3. Proteins 4. Lipids Four basic building blocks involved in catabolic reactions: 1. Monosaccharides (glucose) 2. Amino acids 3. Fatty acids (glycerol) 4. Nucleotides Anabolic reaction: BUILD larger and more complex molecules FROM smaller molecules Requires energy Catabolic reaction: large molecules are BROKEN down INTO smaller molecules Releases energy Endothermic reactions: absorb heat Exothermic reaction: release heat Carbohydrate PRIMARY source of energy; provide energy because they can convert to glucose Take the form of CH2O Polysaccharide Lipids Soluble in non polar solvents; hydrophobic Similar to hydrocarbons Roles include energy storage and structural functions 28  Tuesday, August 25, 2020 Fats: long chains of fatty acids Phospholipids: have phosphate group rather than fatty acid Glycerides: fat and oil; formed from fatty acids and glycerol Proteins Formed from amino acids Polypeptides: 10-100 peptides linked together Condensation reaction: water loss from molecules joining together Hydrolysis reaction: eater is added to smaller molecules Peptide: two or more amino acids Enzymes Proteins with strong catalytic power Greatly accelerate speed Deals with reactants (substrates) Enzymes are selective “key in the lock” analogy: a certain enzyme only fits with a certain substrate Nucleic Acids Composed of nucleotides Through hydrolysis, it is broken down by enzymes to produce shorted strings of RNA and DNA Macromolecular nucleic acid polymers are formed from nucleotides Nitrogen fixation: used to synthesize nucleotides for DNA and amino acids for proteins Nucleic acids: store information and energy and are also catalysts DNA Chromosomes consists of genes Genes are made up of DNA— nucleic acid located in nucleus DNA in mitochondria DNA Structure 29  Tuesday, August 25, 2020 Double helix shape Consist of nucleotides— consist of five-carbon, a phosphate group and nitrogenous base Side rails or backbone are consisted of covalently bonded sugar and phosphate Bases attached to hydrogen bonds Four types of nitrogenous bases: Adenine, guanine, cytosine, and thymine A pairs with T; C with G Purines and Pyrimidines Pyrimidine bases include cytosine, thymine, and uracil Purine bases: adenine and guanine Codons Group of three nucleotides on mRNA Code for a single amino acid 64 codons but 20 amino acids AUG = start codon; UAA, UGA, and UAG = stop codons DNA Replication Controlled by enzymes Enzyme helices instigates the deforming of hydrogen bonds between bases to split two strands Replication fork: DNA that is inbound to be replicated U replaces T RNA Types of RNA Helper to DNA rRna: used to study relationships in organism mRNA: carries a copy of a strand of DNA and transport it from nucleus to cytoplasm 30  Tuesday, August 25, 2020 Transcription = process in which RNA polymerase copies DNA into RNA Translation = ribosomes are used transcribed RNA to put needed proteins together tRNA: helps with the translation process; found in cytoplasm Differences between RNA and DNA RNA: A, G, C, and U** Single strand One backbone DNA A, G, C, and T Double strand Two side rails MENDEL’S LAWS Laws of segregation: two alleles and that half of the total number of alleles are contributed by each parent organism Law of independent assortment: traits are passed on randomly and are not influenced by other traits Gene, Genotype, Phenotype, and Allele Gene: is a portion of DNA that identifies traits Part of genetic code All genes form the genotype Includes genes that may not be expressed Phenotype: the physical, visual manifestation of genes How genes have been affected by environment Allele: variation of a gene aka trait Height, eye color Dominant and Recessive Dominant = uppercase; requires one gene of a pair for it to be expressed in a phenotype Recessive = lowercase; requires both genes 31  Tuesday, August 25, 2020 Monohybrid and Hybrid Crosses Monohybrid cross: cross involving only one trait Dihybrid cross: more than one trait; more combos are possible Non-Mendelian Concepts Co-dominance Refers to the expression of both alleles so both traits are shown Incomplete Dominance Both dominant and recessive are expressed, resulting in a phenotype that is mixed with both Polygenic Inheritance Traits influences by more than one gene, and takes into account environmental influences on development Multiple Alleles Only two alleles make up a gene A gene with at least three possible alleles BASIC ATOMIC STRUCTURE Pieces of an Atom All matter consists on atoms Consist of nucleus and electrons Nucleus = protons and neutrons; + charge Electrons = - charge; orbit around nucleus Atoms can bond to form molecule Neutron is =; ion is not = Models of Atoms Atomic radius: avg. distance between uncles and the outermost electron Atomic Number 32  Tuesday, August 25, 2020 Number of protons** Atoms with neutral charge have an atomic number that is = to the number of electrons Atomic Mass Mass number # of protons + neutrons = mass; A = Z + N** Neutron = atomic # - atomic mass** Isotopes 80 elements have one or more stable isotopes Radioactive isotopes have unstable nuclei ELECTRONS Orbit nucleus; layers, shells, or clouds Negative charge Lepton family Valence shell: outermost electron shell Valence electrons: outer shell electron that determines bonding behavior Chemical Bonds and Electron Shells Negative-postive attraction between and electron and the nucleus of an atom K-shell = 2 electrons; L-shell = 8; M-shell = 18; N-shell = 32 Polar bond: separation of charge; one end is - and the other is + Hydrogen-oxygen Ions Negative ion: atom gains electron Positive ion: loses electron Ionic bond: formed between ions with opposite charges Electrons are transferred 33  Tuesday, August 25, 2020 CHEMICAL BONDS BETWEEN ATOMS Atoms with same element form molecules or crystalline solids When different atoms bind, compound is made Ionic bonding: when an atom gains or loses electrons it becomes negatively or positively charged -> ion Relationship between two oppositely charged ions Transfer from one atom to another Covalent bonding: atoms that share electrons Electrons shared equally = non-polar bond Electrons share unequally = polar bond Occurs more when having similar electronegativities Electronegativity: how capable an atom is of attracting a pair of bonding electrons Nonmetals are more likely to form more covalent bonds than metals Hydrogen bonding: interacts with a hydrogen atoms Cation: positive ion from losing electrons Anion: negative ion from gaining electrons COMPOUNDS Element = most basic type of matter Smallest unit = atom Compound: combination of two or more elements Molecule = smaller independent of an element or compound Diatomic elements: H, N, O PERIODIC TABLE 34  Tuesday, August 25, 2020 Properties of the elements depend on atomic structure and vary with atomic number Horizontal = period; vertical = groups Group number reveals the number of outer shell electrons Metals, Nonmetals, and Metalloids Metals = left side and center of the table Alkali metals, and alkaline earth metals Transition metals, and inner transition metals Nonmetals = right side Halogens and Noble gases Metalloids = zigzag line CHARACTERISTIC PROPERTIES OF SUBSTANCES Intensive and Extensive Properties Intensive: DO NOT depend on the amount of matter or quantity of the sample Won’t change if the sample size is increased or decreased Include color, hardness, melting point, boiling point, density, ductility, malleability, specific heat, temperature, concentration, and magnetization Extensive: DO depend on the amount of matter or quantity of the sample Changes if sample size is increase or decreased Sample size increased = property increased and vice versa Include volume, mass, weight, energy, entropy, number of moles, and electrical charge Physical Properties of Matter Can be observed or measured Mass = amount of substance; weight = gravitational pull of earth Density = m/v Specific heat: heat capacity per unit mass Q=mcΔT Conduction 35  Tuesday, August 25, 2020 Thermal equilibrium = same temp and no net heat transfer Conduction: heat transfer by contact Properties of Water Water is cohesive, adhesive, makes a good solvent Hydrogen Bond Weaker than covalent and ionic bond Short-lived Important components of proteins, nucleic acids, and DNA Passive Transport Mechanism: Diffusion and Osmosis Passive transport mechanism: simple and facilitated diffusion and osmosis No energy needed Diffusion: particles transported from areas of higher concentration to lower concentration Facilitated diffusion: transported by a carried protein Osmosis: diffusion of water through semi-permeable membrane from lower to higher solute concentration STATES OF MATTER Matter = mass and occupy space Three states: solid, liquid, and gas Solid: rigid; strong bonds Definite volume and shape Liquid: move around; weak bonds Volume = constant and assumes shape of container Gases: move independently, far apart; do not form bonds Assumes volume and shape of container Changes in States of Matter Solid to liquid = melting Liquid to solid = freezing Liquid to gas = vaporization Gas to liquid = condensation** 36  Tuesday, August 25, 2020 Solid to gas = sublimation Gas to solid = deposition OVERVIEW OF CHEMICAL REACTIONS Catalysts: accelerate reactions** Inhibitors: decreases reaction rates READING AND BALANCING CHEMICAL EQUATIONS Reactants = left side; product = right side; arrows = change Coefficient has to be whole numbers Law of Conservation of Mass In a chemical reaction, matter is neither created nor destroyed REACTIONS Basic Mechanisms Reactions and reactivity depend on octet rule Changes in reaction may be in composition or configuration Reactions depend on reactant FIVE BASIC CHEMICAL REACTIONS Combination Reactions Two or more reactions to form a single product A + B —> C Synthesis or addition reactions Decomposition Reactions 37  Tuesday, August 25, 2020 Single compound breaks into two A —> B + C Analysis reaction 2H2O —> 2H2 + O2 Single Replacement Reactions Displaced by another to form final product A + BC —> B + AC Double Replacement Reactions Ions or bonds are exchanged by two compound to form different compounds AC + BD —> AD + BC Combustion Reactions Involves fuel and an oxidant that produces heat or light Catalysts Help change the rate of reaction without changing the form Enable more particles to react which lowers activation energy pH Potential of hydrogen: concentration of hydrogen ions Substances fall between 0 and 14 on pH scale Pure water = neutral pH (7) Acidic = 7 Bases Bitter taste, soapy or slippery texture Alkaline Acids Sour change litmus paper to red 38  Tuesday, August 25, 2020 Produce gaseous H2 in reaction with some metals Produce salt precipitates in reaction with bases 39