AP modules 1-4.docx

Objective 1: Define anatomy and physiology. See OpenStax A&P pages 8–9. Anatomy is defined as the study of structure and the relationships among structures. Gross: larger and no need of microscope Microscopic: only with microscope and magnification 2 general approaches: Regional: study of...

Objective 1: Define anatomy and physiology. See OpenStax A&P pages 8–9. Anatomy is defined as the study of structure and the relationships among structures. Gross: larger and no need of microscope Microscopic: only with microscope and magnification 2 general approaches: Regional: study of the interrelationships of all structures in a specific body region Systemic: study of structures that make a discrete body system group of structures that work together to perform a unique body function Physiology is the study of how body structures function chemistry and physics of body structures and the ways they work together to support functions of life Objective 2: Describe the different levels of organization in the human body. See OpenStax A&P pages 9–11; Fig. 1.3. Chemical: Chemical building blocks are molecules. They are made from bonding/ joining of atoms which are the simplest building blocks of matter and have all its unique properties when they undergo chemical reactions and join together. Cellular level: cells are basic independent structural and functional units of living organisms which are responsible for performing or initiating the physiological functions of living organisms. They are composed of variety of molecules that come together and form organelles and the fluid cytoplasm muscle cell Tissue level: group or collection of cells and substances around them that are similarly specialized to perform particular special functions and they have same embryonic origin smooth muscle tissue Organ level: when two or more different tissues combine together to form structures with a definite form that have specific functions bladder is combination of skeletal and smooth muscle cells Organ systems: when two or more related organs with common functions that work closely together to perform major functions of life urinary system kidneys and bladder Organism: collection of structural and functional organ systems that work harmonically together in order to perform all the needed functions that are necessary for life form an independent organism Figure 1.3: Levels of Structural Organization of the Human Body. The organization of the body is often discussed in terms of six distinct levels of increasing complexity, from the smallest chemical building blocks to a unique human organism. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and- physiology/pages/1-introduction.) Objective 3: List and describe the major body systems, and state the general function of each. See OpenStax A&P pages 11–14; Figs. 1.4, 1.5. The systems of the human body are the : Integumentary: skin, nails, hair cover the surface of body in order to enclose internal structures, provide a barrier, they provide a place/ site for many sensory receptors. Skeletal: bones, cartilage, joints allow movement with help of muscle system, provide support and structure for body, protect internal organs Muscular: skeletal muscles, tendons specialized to contract to allow movement, produce heat so help maintain body temperature, generate force, help in maintaining posture Nervous: brain, spinal cord and peripheral nerves monitor the environment and are capable of detecting sensory information which then they process it and activate coordinated body responses, also contribute to homeostasis Endocrine: pituitary gland, adrenal gland, thyroid gland, pancreas, ovaries and testes secrete hormones which are transferred throughout the body to different tissues and organs in order to regulate body processes Cardiovascular: heart, blood vessels they deliver oxygen and nutrients to all cells throughout the body, equalize the temperature in the body since they have a lot of water which has high capacity for heat Lymphatic thymus, lymph nodes, lymphatic vessels, spleen they drain into blood vessels to return fluids and other molecules that cannot directly enter the bloodstream such as lipids from intestines, they also protect body against pathogens by their white blood cells Respiratory nasal passages, trachea, lungs deliver oxygen to blood and remove carbon dioxide from the body. Digestive stomach, liver, gallbladder, large intestine, small intestine breakdown and process ingested foods into smaller molecules that can be used by the body to build structures or for energy, remove wastes from undigested foods Urinary kidneys, urinary bladder remove and excrete wastes from blood and regulates the the water balance in the body Male reproductive: epididymis, testes they are responsible for making sex hormones and gametes (sperms) and delivering them to the female Female reproductive: mammary glands, ovaries, uterus make sex hormones and gametes (eggs) and they house and protect the embryo/ fetus till birth and they also make milk for infants Objective 4: List and describe the major characteristics of life (life processes). See OpenStax A&P pages 14–16; Fig. 1.6. All living things have certain characteristics that distinguish them from nonliving things. The life processes of humans include: Metabolism sum of all the chemical reactions including catabolism and anabolism that occur in the body one of basic functions of an organism is to consume/ingest energy and molecules in our food and convert them into a fuel for movement, performing body functions and building and maintaining body structures. Anabolism: building larger and more complex substances and needed structures or chemicals by joining smaller and simpler molecules. It requires energy and is endergonic body absorbs and stores energy in the form of ATP that can be moved to parts of body that require fuel for their cellular activities Catabolism: breaking down larger and more complex substances into smaller and simpler molecules. It releases energy and is exergonic. This is smaller molecules then can be used for anabolic reactions body releases the energy stored in ATP to fuel the functions and cellular activities Responsiveness living things have the capability to monitor and detect any changes in their external and internal environments and respond to those changes/ stimuli properly Movement is the motion of whole body, individual organs or cells, as well as the organelles within the cells Growth ability to increase in size and complexity due to increase in size of cells, or increase in number of cells or both combined Differentiation this is part of development which includes all the changes that occurs in the body and is specifically the process in which cells change from unspecialized state to specialized state in terms of structure and function in order to perform particular and specific functions Reproduction formation of new individual organisms or formation of new cells in order to grow, repair or replace other cells Figure 1.6: Metabolism. Anabolic reactions are building reactions, and they consume energy. Catabolic reactions break materials down and release energy. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 5: Define homeostasis, and explain its importance to survival. See OpenStax A&P pages 9, 20. Homeostasis refers to steady state in the internal environment of body to maintain equilibrium and is achieved by the continuous independent or joined actions of body’s regulatory processes that include nervous system and endocrine system. Nervous systems they act by sending nerve impulses to counteract any detected changes or disruptions. Their actions are very fast and cause rapid changes Endocrine system act by secreting hormones in order to regulate and maintain homeostasis. Hormones usually work at a slower speed and pace. Objective 6: Define a feedback system, and list the component parts of a feedback loop. See OpenStax A&P pages 20–21; Fig. 1.10. Feedback system is the cycle of events and physiological processes during which the status of a condition is continuously monitored to gather information and then this information are reported to a central control region to either reverse any deviations from the set points or enhance the changes and deviations. It has 4 components: Stimulus: any disruptions that lead to changes in a controlled condition and it leads to deviations from the set points Receptor: is the component that monitors the changes in a controlled condition caused by stimulus and reports the information to control center by either sending nerve impulses or chemical signals Control center: the component that sets the ranges and values for maintenance of a controlled condition and when they get information from receptors, they evaluate and compare them to the set values and if needed they generate commands to the effectors/ body structures Effectors: these receive the commands and outputs from the control center in order to produce a response or an effect to change the controlled conditions. they mainly respond in a way to resist changes and return the condition to homeostasis. Objective 7: Define, explain, and give examples of positive and negative feedback loops. See OpenStax A&P pages 21–23; Figs. 1.10, 1.11. Negative feedback loop physiological processes that resist the changes in the state of controlled condition by reversing the original stimulus in order to return the body to homeostasis Body temperature regulation: If temperature is higher than 37 degrees: Vasodilation of blood vessels in the skin and surface of body increase blood flow to surface warmer blood from core goes to surface in order to release its heat Increased blood flow leads to increased activity of sweat glands so they secrete more sweat which is then evaporated from skin and radiates the heat to the external environment The depth of respiration increases more breathing through the open mouth which leads to increase heat loss by lungs If temperature is lower: The blood flow to the surface is decreased in order to keep the heat within the body core and also the blood that returns from extremities are sent to deep network of veins Brain is stimulated to send more random nerve impulses to skeletal muscles leading to more contractions of them and this is known as shivering. More contraction leads to increased metabolic activity and heat production Thyroid glands release more thyroid hormones that increase the metabolic activity and heat productions in all the cells throughout the body Adrenal glands release adrenaline hormones that stimulate the glycogen molecules to breakdown into glucose molecules for fuel. This process also increases metabolic activity and heat production Figure 1.10: Negative Feedback Loop. Here, a stimulus—a deviation from a set point—is resisted through a physiological process that returns the body to homeostasis. (a) A negative feedback loop has four basic parts, (b) e.g., body temperature regulation. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy- and-physiology/pages/1-introduction.) Positive feedback loop: enhances the changes and deviations caused by the original stimulus they should have a definite end point Childbirth: Original stimulus: first contractions that push the body towards the cervix Receptors: the stretch sensitive cells are the nerve cells that detect the initial stretches caused by stimulus and send the info to the brain Control center: pituitary gland at the base of the brain is stimulated the release the hormone oxytocin in the bloodstream Effectors: Smooth muscles of the uterus are stimulated by the oxytocin which causes stronger contractions that in turn push the baby further down the end of birth canal Figure 1.11: Positive Feedback Loop. Normal childbirth is driven by a positive feedback loop. A positive feedback loop results in a change in the body’s status, rather than a return to homeostasis. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 8: Define disease, symptom, and sign, and relate each to homeostatic imbalance. A disruption of homeostasis can lead to disease and death. Disorder : general term that is used when there is an abnormality of function in the body Disease: specific term that is used when disruptions in functions and homeostasis lead to an illness that is characterized by set of recognizable and known signs and symptoms. Symptoms: these are subjective changes that occur in body functions and are not observable by anyone else headache or nausea Signs: objective changes that occur in body functions that can be observed and also be measured by a clinician fever, rash, heart rate Objective 9: Describe the anatomical position by using the descriptive and directional terms that refer to body structures, surfaces, and regions. See OpenStax A&P pages 23–25; Figs. 1.12, 1.13. Anatomical position: standardized method that uses directional and descriptive terms to refer to different structures in the body and is used for observation or taking body images. It allows anatomical references to be precise and consistent all the time. In the anatomical position, the subject stands erect; her/his upper extremities (arms) are placed at their side; the palms of their hands are turned forward; and their feet are flat on the floor. Figure 1.12: Regions of the Human Body. A male is shown in the anatomical position in an (a) anterior view, and a (b) posterior view. The regions of the body are labeled in boldface. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Directional terms the terms that we use to precisely locate a body part relative to another. It is also very useful to describe the relationship between the body parts in shorter ways. dorsal, superior, medial, ventral, inferior, lateral, and proximal. Figure 1.13: Directional Terms Applied to the Human Body. Paired directional terms are shown as applied to the human body. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 10: Identify the planes of reference used to depict the structural arrangement of the human body. See OpenStax A&P pages 25–26; Figs. 1.13, 1.14. Body planes: Are imaginary flat surfaces that are used to divide body or structures within the body into definite areas. Sagittal divide into left and right midsagittal or parasagittal Frontal coronal front and back Transverse horizontal cross-sectional Oblique Sections: two dimensional flat surfaces that are created when 3 dimensional body structures are cut through. They are named based on the plane that was used to cut them. Figure 1.14: Planes of Sectioning the Body. The three planes most commonly used in anatomical and medical imaging. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy- and-physiology/pages/1-introduction.) Objective 11: Identify the body cavities and list the organs found within each. See OpenStax A&P pages 26–27; Fig. 1.15. Body cavities are spaces that protect, separate, and support the internal organs. Dorsal Body Cavity The dorsal body cavity is located near the dorsal surface of the body; it has two subdivisions—the cranial cavity and the vertebral canal. The cranial bones form the cranial cavity, which surrounds and protects the brain. The vertebral (spinal) canal is formed by the bones of the vertebral column, which surround and protect the spinal cord. Ventral Body Cavity allows changes in size and shape of the internal organs The diaphragm subdivides the ventral cavity into an upper thoracic cavity and a lower abdominopelvic cavity. The thoracic cavity contains two pleural cavities and the mediastinum, which includes the pericardial cavity. Thoracic is enclosed by rib cage. The pleural cavities enclose the lungs, and the pericardial cavity surrounds the heart. The mediastinum is a broad, median partition between the lungs that extends from the sternum to the vertebral column. It contains everything in the thoracic cavity except the lungs. The abdominopelvic cavity is the largest and contains a superior abdominal (digestive) and an inferior pelvic cavity(reproductive) . Figure 1.15: Dorsal and Ventral Body Cavities. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 12: List the regions of the body and the localized areas within each region. See OpenStax A&P pages 27–28; Fig. 1.16. To easily describe the location of the organs, the abdominopelvic cavity can be divided into nine regions by drawing four imaginary lines. In clinical studies, to locate the site of an abdominopelvic abnormality, the abdominopelvic cavity can be divided into quadrants by drawing imaginary horizontal and vertical lines through the umbilicus. Figure 1.16: Regions and Quadrants of the Peritoneal Cavity. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 1: Describe the structure of an atom, and define the term isotope. See OpenStax A&P pages 41–44; Figs. 2.2, 2.3, 2.4. Biochemicals: produced by the body. Elements: are the most fundamental materials of everything All forms of matter are composed of chemical elements, which are substances that cannot be created or broken into simpler substances by ordinary chemical means. They cannot be created by body and are picked up from environment food and air Chemical elements are given letter abbreviations called chemical symbols. Oxygen (O), carbon (C), hydrogen (H), and nitrogen (N) make up 96% of our total body weight. These elements, together with calcium (Ca) and phosphorus (P), make up 98.5% of our total body weight. Structure of Atoms Atoms: smallest quantities of elements that retain all of the unique properties of that element Number of protons determine the element atomic number is the number of protons The units of matter of all chemical elements are called atoms. An element is a quantity of matter composed of atoms of the same type. Atoms consist of a nucleus—which contains positively charged protons and neutral (uncharged) neutrons—and negatively charged electrons that move about the nucleus in different energy levels. Isotopes are different atoms of the same chemical element that have the same number of protons but different numbers of neutrons. A radioactive isotope is unstable and emits radiation (energy). An atom’s atomic number is the number of protons in its nucleus, and the usual number of electrons as well. An element’s mass number is the sum of the number of protons and neutrons in its nucleus. Objective 2: Define ion, molecule, compound, and free radical. See OpenStax A&P pages 49–50. Bonds: electrical attractions that hold atoms in a same vicinity become more stable and less likely to react Ions: atoms that have unequal numbers of protons and electrons due to loss or gain of electrons which makes them become positively or negatively charged. If an atom either gives up or gains electrons, it becomes an ion, which is an atom that has a positive or negative charge due to its unequal number of protons and electrons. Cations are positively charged ions. Anions are negatively charged ions. When two or more atoms share electrons, the resulting combination is called a molecule. chemical subunits of structures A compound is the combination of two or more different atoms, e.g., water (H2O). Free radical: electrically charged atom or group of atoms that have an unpaired electron in their valence shells in order to become stable they have to either gain an electron from another molecule or lose/donate their unpaired electron Antioxidants are substances that inactivate oxygen-derived free radicals. Objective 3: Describe the different types of chemical bonds, noting their relative strengths. See OpenStax A&P pages 49–54; Figs. 2.8, 2.9, 2.10, 2.11. Chemical bond: the attraction forces that hold atoms of a molecule Ionic Bonds Attraction forces that hold ions of opposite charges together These compounds generally exist as solids but they ionize in solutions Covalent Bonds Formed when atoms of a molecule share electrons and form a mutually stabilizing relationship most common in body Polar covalent bonds: have regions with opposite charges due to their unequal sharing of electrons partially charged since their charges are less than a single electron The polar covalent bonds between hydrogen atoms with either oxygen or nitrogen allow hydrogen bonds to form Non-polar covalent bonds: these do not have regions that are more positive or more negative than others and this is because the sharing of negative electrons is relatively equal to the attractive/ pulling forces of positive protons in the nuclei of the atoms Covalent bonds are the strongest bonds. Hydrogen Bonds Formed when a hydrogen with a partial positive charge that is already bonded to either nitrogen or oxygen by polar covalent bonds is attracted to another partially negative charged atom of another molecule form links between molecules to provide strength, stability and help determine the 3D shape of larger molecules Objective 4: Describe the different forms of energy. See OpenStax A&P pages 54–55. A chemical reaction occurs when new bonds are formed or old bonds break between atoms. The starting substances of a chemical reaction are known as reactants. The ending substances of a chemical reaction are the products. In a chemical reaction, the total mass of the reactants equals the total mass of the products (the law of conservation of mass). Metabolism refers to all the chemical reactions occurring in an organism. Forms of Energy and Chemical Reactions Energy is the capacity to do work: Potential energy is the energy stored by matter due to its position (for example, a ball at the top of a hill). Chemical energy is a form of potential energy stored in the bonds of compounds or molecules. Kinetic energy is the energy associated with matter in motion. Objective 5: Describe the types of chemical reactions. See OpenStax A&P pages 55–56; Fig. 2.12. Synthesis reactions occur when two or more atoms, ions, or molecules combine to form new and larger molecules. These reactions are anabolic, which means that bonds are formed. Endergonic: absorb more energy than they release anabolic store not only the chemical energy in the original components but also the energy that fueled the reaction and store all in their bonds they get the extra energy from exergonic reactions In a decomposition reaction, a molecule is broken down into smaller parts. These reactions are catabolic, which means that chemical bonds are broken in the process. Exergonic: release more energy than they absorb catabolic some chemical energy in food is stored into molecules that body use but some of it is released as for example heat Exchange reactions: bonds are both formed and broken so the components of original reactants are rearranged energy is absorbed, stored and released reversible but the more predictable path is the direction that requires less energy Note In oxidation-reduction reactions, electrons are taken from the atom being oxidized by the atom being reduced. Oxidation is the loss of electrons from a molecule, which results in a decrease in the potential energy of the molecule. Reduction is the gain of electrons by a molecule, which results in an increase in the potential energy of the molecule. Objective 6: Differentiate between organic and inorganic compounds. See OpenStax A&P pages 58, 64–65; Table 2.1. Inorganic compounds usually lack carbon and are simple molecules organic compounds always contain carbon and hydrogen, always have covalent bonds, and usually contain oxygen. Organics are created by living things carbohydrates, lipids, proteins, nucleotides They have a core carbon that has 4 valence electrons that readily share via covalent bonds. They make carbon skeletons by binding to each other. Carbons and hydrogens make hydrocarbons They also bind functional units are group of atoms linked strongly by covalent bonds and tending to function in chemical reactions as single unit and their members do not part away 5 functional groups: Carboxyl : O- C-OH found in fatty acids, amino acids and many other acids Hydroxyl: O-H they are polar, part of all 4 groups in body, and they are involved in dehydration synthesis and hydrolysis Amino: N – H2 found in amino acids, the building blocks of proteins Methyl: C- H3 found within amino acids Phosphate : P-O4 2- phosphate groups found in nucleotides and phospholipids Macromolecules : stable organic molecules due to their affinity for covalent bonding bind and form larger and more complex molecules. Some of them are made up of several copies of single units called monomers Dehydration synthesis: covalent bonds are formed between monomers or simple molecules by releasing a molecule of water. This happens because of molecule release a H and the other one releases a OH Dehydration synthesis occurs when two simple molecules join together by covalent bonds eliminating a molecule of water in the process. Hydrolysis: covalent bonds between monomers or subunits of larger molecules are broken down by adding a molecule of water one gets the OH and the other gets the H Hydrolysis breaks the covalent bonds within a large molecules to break them down into simpler ones by adding a molecule of water. Objective 7: Discuss the properties of water. See OpenStax A&P pp. 58–60; Fig. 2.14. Water is the most important and also abundant inorganic compound in all living organisms. This is because: Universal solvent : polarity of water allows them to strongly attract other charged molecules and ions and polar covalent molecules and dissolve them. So by doing this they can move the dissolved substances throughout the body. They also dissolve wastes. Ideal medium for most chemical reactions in body: majority of chemical reactions occur between compounds that are dissolved in water since water enables the reactants to collide and form products by hydrolysis or dehydration synthesis so water itself participates as a reactant or is produced by reactions Water has a high heat capacity. It can absorb or release a relatively large amount of heat with only a modest change in its own temperature it can absorb the heat from chemical reactions without greatly increasing in temperature. Also helps keep the body cool. The cohesion of water molecules creates a high surface tension, which is a measure of the difficulty involved to stretch or break the surface of a liquid. Water is a major part of mucus and other lubricating fluids it cushions and lubricates lubricate actions of joints , watery fluids keep food flowing through the digestive tract . it also protects cells and organs from physical trauma by cushioning them cushion brain within the skull, protect delicate nerve tissues of the eye, cushion a developing fetus Objective 8: Define the terms acid, base, salt, and ion. See OpenStax A&P pages 60–62; Figs. 2.14, 2.15, 2.16. The positive and negative charges on the water molecule attract anions and cations and pull them away Acids: substances that dissociate/ ionize into H+ and anions when they are dissolved in water Bases: substances that dissociate into OH- and cations when dissolved in water. They are also capable of gaining a H+ Strong acids and bases readily ionize and release all their H or OH in a aqueous solution Salts: substances that break down or ionize into cations and anions other than H+ and OH- when they are dissolved in water Electrolyte: compounds/substances that ionize and dissociate into positive and negative ions when they are in a solution / water. The ions form dipole-ion bonds with water molecules. They can conduct electrical current in a solution functions of ions in transmitting nerve impulses or muscle contractions crystal salts Bases are proton acceptors so if they bind to free protons released by acid , they form a water molecule and by this removing of H, they reduce the solution’s acidity Objective 9: Define pH, and explain the functioning of buffers. See OpenStax A&P pages 62–64; Fig. 2.17. pH: concentration of H+ in a solution and a pH scale that runs from 0-14 is used to show the basicity or acidity of a solution pH of 7.0 equals 10-7 or 0.0000001 moles of H+/L, which is neutrality. Values below 7 indicate acid solutions ([H+] > [OH-]). Values above 7 indicate alkaline solutions ([H+] < [OH-]). Body fluids must always contain specific quantities of acids and bases. Biochemical reactions are extremely sensitive to even small changes in acidity or alkalinity. pH of blood is 7.4 and this slightly basicity allows it to reduce the acidity resulted from CO2 constantly being released into blood all cells depend on the homeostatic regulation of acid base balance at a pH of approx. 7.4 mechanisms that help this regulate pH of 7.4: exhaling CO2 through breathing excretion of chemicals in urine internal release of buffers into body fluids if there is a decrease below 7.35 in the pH of bodily fluid, they act as a weak base and bind to the excess hydrogen ions. If pH rises above 7.45 the buffer will act as weak acid and contribute to concentration of Hydrogen ions buffer systems: that usually consist of a weak acid and a weak base are used to maintain the specific pH values of different parts of body they function by converting a strong acid or strong base into weak acid or base main one is the carbonic acid / bicarbonate buffer system in stomach strong hydrochloric acid releases from cell in the lining of stomach and releases all its H into the stomach’s watery environment this aids in digestion and also to kill ingested microbes Food mixed with hydrochloric acid would burn the intestine so after the stomach, bicarbonates that are weak bases are released and accepts some of H protons reducing the acidity of solution Objective 10: List the subcategories of carbohydrates, and give examples for each subcategory. See OpenStax A&P pages 64–68; Table 2.1, Figs. 2.18, 2.19, 2.20. Can be used to make ATP most of energy needed for life – neurons and RBC only use glucose. All other cells can use it but not dependent only on it can be used build other structures (ribose) they are present as glycoproteins in cells – cell recognition stored as food reserves in liver and skeletal muscle cells - Obtained from plant based foods and dairy products Carbohydrates—including sugars, starches, glycogen, and cellulose—provide most of the energy needed for life. Starches: polymers of glucose, long chains called amylose or branched chains called amylopectin stored in plant based foods and are easy to digest Glycogen: polymers of glucose stored in tissues of animals in liver and muscles human body store excess glucose as glycogen Cellulose: polysaccharide that is the primary component of plant cell walls and is referred to as fiber since it is not digestible Some carbohydrates are converted to other substances, which are used to build structures and to generate ATP. Other carbohydrates function as food reserves. Carbohydrates are divided into three major groups based on their size: monosaccharides, disaccharides, and polysaccharides. Monosaccharides and Disaccharides: The Simple Sugars Disaccharides are formed from two monosaccharides by dehydration synthesis. Hydrolysis can be used to split disaccharides back into simple sugars. Their bonds are called glycosidic bonds. Polysaccharides, the largest carbohydrates, are known as complex carbohydrates; they can include hundreds of monosaccharides. The principal polysaccharide in the human body is glycogen, which is stored in the liver or skeletal muscles Monosaccharides: glucose, fructose, galactose, ribose and deoxyribose Disaccharides: sucrose (table sugar) glucose + fructose maltose (malt sugar) glucose + glucosa lactose (milk sugar) glucose + galactose consumed in diet but cannot be used directly so they are split into their monosaccharides in digestive tract by hydrolysis In the breakdown of glucose for fuel, molecules of ATP are produced (ribose sugar, adenine base, and three phosphate groups) Every time the phosphate bonds of ATP break, free energy is released which supplies ready energy to the cell Objective 11: Identify and describe the subclasses of lipids, and distinguish between saturated and unsaturated fats. See OpenStax A&P pages 69–72; Figs. 2.21, 2.22, 2.23. Lipids, like carbohydrates, contain carbon, hydrogen, and oxygen; however, unlike carbohydrates, they do not have a 2:1 ratio of hydrogen to oxygen. Mostly made up of hydrocarbons which make them hydrophobic and the few oxygens are often at the periphery of molecule Lipids have fewer polar covalent bonds, and thus they are mostly insoluble in polar solvents such as water (they are hydrophobic). However, lipids are soluble in non-polar solvents such as chloroform or alcohol. Triglycerides are the most plentiful lipids functions: protection, insulation, and energy (both immediate and stored). Triglycerides are major fuel sources when asleep the majority of energy is from these that are stored in adipose tissues they also fuel long slow physical activities such as hiking and contribute modestly to energy for vigorous physical activity. Dietary fat also assists the absorption and transportation of non polar fat soluble vitamins A, D, K, E Stored body fat also protects and cushions body bones and internal organs insulation to retain body heat Their Structures: Glycerol backbone which has three carbons in its core and one end of them they have a hydroxyl group Three fatty acid chains which are hydrocarbons with carboxyl groups on one end and methyl group on the other end the OH from carboxyl groups of each fatty acid chain binds to the hydrogen of the hydroxyl groups of each carbons in glycerol and release a water therefore they chains attach to the carbons of glycerol by dehydration synthesis 3 water molecules are released The level of saturations affect their shape so either straight chains or kinky chains Fatty acid chains with no carbon double bonds are saturated with hydrogen so they are straight and form rigid chains packed tightly together saturated increase heart disease If one carbon double bond they are monounsaturated and cannot pack tightly If more than two carbon double bonds then they are polyunsaturated unsaturated reduce the risk Phospholipids are structurally similar to triglycerides and are important membrane components. Their Structure: a diglyceride ( a glycerol with two fatty acid chain) because the third carbon binding site in glycerol is taken up of the phosphate group which is attached to a polar head region 2 hydrophobic fatty acid chains and a polar phosphorous containing group are attached to the glycerol backbone Steroids Their structure: four interlocking hydrocarbon rings that can be bound to variety of other atoms and molecules. Examples include dietary lipid cholesterol, and the sex hormones estrogen and testosterone. Cholesterol is synthesized in liver of humans and animals so is also present in most animal based foods. it has hydrophobic hydrocarbon rings but also has a polar hydroxyl group that is hydrophilic . so important part of bile acids, building blocks of hormones and are found in cell membrane to regulate the flow of substance in and out of cell Objective 12: Describe the structure of amino acids and proteins. See OpenStax A&P pages 72–75; Figs. 2.24, 2.25, 2.26. Structure of amino acids organic molecules composed of: amine group Carboxyl group Hydrogen R group / side chain – different sizes, polar or non-polar help determine the shape of proteins which in turn determine their functions Structure of proteins: Primary: sequence of amino acids that are bound to each other by covalent peptide bonds determine their shape and folding 3D functional structure Secondary: alpha helices and beta pleated sheets folded structures due to hydrogen bonds between amino acids of a same polypeptide chain Tertiary: 3 dimensional structures of proteins further folding of secondary structures which leads to formation of hydrogen bonds between amino acids that are further from each other on the original chain. Also may have covalent disulfide bonds Quaternary: when two or more tertiary structures of different polypeptide chains interact with each other and become subunits of larger complexes Figure 2.25: Peptide Bond. Different amino acids join together to form peptides, polypeptides, or proteins via dehydration synthesis. The bonds between the amino acids are peptide bonds. Functions of proteins: Structure: protein fibers Enzymes: biological catalysts Transport material and substances: hemoglobin Allow muscle contractions: movement and heat : actin and myosin Protection: connective tissues Regulate processes: both acidic carboxyl and basic amine group so they are great buffers Protein denaturation: Changes and disruptions in the characteristic and functional structures of proteins due to physical or chemical reasons such as extreme heat, acidity, basicity or some substances loss of their functional structure and loss of function 11 amino acids are made in body by using components of other molecules but 9 are essential amino acids Objective 13: Discuss the structure and function of enzymes. See OpenStax A&P pages 57, 74–76; Figs. 2.13, 2.27. Enzymes: biological catalysts found in the body of living organisms. They can be made of RNA or proteins. They increase the rate chemical reactions by facilitating the interactions between the substrates. This is done by lowering the energy that is required to be invested to break the bonds between the substrates which then allow new arrangements to form. Substrate: reactant in an enzymatic reaction Characteristics: Highly specific and selective each chemical reaction requires its own specific enzyme substrates have different sizes, shapes and charges so they can only bind with active sites that correspond to their unique characteristics. Enzymes have specifity but some have the ability to act on several different structurally related substrates, Enzymes are extremely efficient with respect to the number of substrate molecules with which they react. Enzymes speed up chemical reactions by increasing the frequency of molecule collisions, lowering the activation energy, and properly orienting colliding molecules. Mechanism: Induced fit model: temporary conformational changes in the active site when they are bound to their substrates along with simultaneous formation of the transition state. Substrates bind to the active sites on the enzymes and form the enzyme substrate complex The enzyme substrate complex undergoes conformational changes in order to increase the frequency of substrate collisions and also orienting them in a way relative to each other that is optimal for them to interact increase the rate of collision and positioning them to increase the chances that their valence electrons can interact with each other. these changes are done to find the best fit between the transition state which is the structural intermediate between substrate and products and the active site The energy needed for the chemical reaction to occur by breaking the bonds between the substrates is reduced activation energy is reduced the rearrangements to form products can now happen Products leave the enzyme Figure 2.27: Steps in an Enzymatic Reaction. According to the induced-fit model, the active site of the enzyme undergoes conformational changes upon binding with the substrate. (a) Substrates approach active sites on enzyme. (b) Substrates bind to active sites, producing an enzyme-substrate complex. (c) Changes internal to the enzyme-substrate complex facilitate interaction of the substrates. (d) Products are released and the enzyme returns to its original form, ready to facilitate another enzymatic reaction. Figure 2.13: Enzymes. Enzymes decrease the activation energy required for a given chemical reaction to occur. (a) Without an enzyme, the energy input needed for a reaction to begin is high. (b) With the help of an enzyme, less energy is needed. Objective 14: Discuss the structure and function of nucleic acid. See OpenStax A&P pages 76–78; Figs. 2.28, 3.22. Nucleic Acids: Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA) Structure: Large organic molecules which their basic units are nucleotides. The nucleotides are made of a pentose sugar, one or more phosphate group, and a nitrogenous base. Carbon, hydrogen, oxygen, nitrogen, phosphorus Type and functions: DNA: deoxyribose-containing nucleotide that stores genetic information. store genetic information form the genetic codes that encode proteins needed for cells to regulate their function and structure. Deoxyribose sugar. Double helix DNA strands that are each polymers of nucleotides and the two strands wound around each other RNA: they carry the instructions from genes from nucleus on how ribosomes assemble amino acids into proteins Nitrogenous bases: A and G purine 2 rings C, T, U pyrimidine single rings Figure 2.28: Nucleotides. (a) The building blocks of all nucleotides are one or more phosphate groups, a pentose sugar, and a nitrogen-containing base. (b) The nitrogen-containing bases of nucleotides. (c) The two pentose sugars of DNA and RNA. The DNA and RNA backbones are formed by dehydration synthesis between pentose sugar of one nucleic acid monomer and the phosphate group of another monomer phosphodiester linkage sugar phosphate backbone In terms of DNA, the two strands attach due to the hydrogen bonds between their bases and make a double helix The sequence of nitrogen containing bases within strands of DNA form the genes that act as a molecular code instructing cells in assembly of amino acids into proteins RNA but is a single strand of sugar phosphate backbone studded with base. mRNA is created during protein synthesis to carry the genetic information from the DNA to the cell’s protein manufacturing center in cytoplasm, the ribosomes. Objective 15: Discuss the structure and function of adenosine triphosphate (ATP). See OpenStax A&P pages 68, 77–78; Fig. 2.30. Adenosine triphosphate (ATP) is the principal energy-storing molecule in the body. ATP consists of three phosphate groups attached to an adenosine unit, which is composed of adenine and the five-carbon sugar ribose. When energy is liberated from ATP, it is decomposed to adenosine diphosphate (ADP) and phosphorus (P). ATP is manufactured from ADP and P using the energy supplied by various decomposition reactions, particularly that of glucose breakdown The two covalent bonds linking the three phosphate groups store a significantly large amount of potential energy and every time these bonds break due to hydrolysis and ATP becomes ADP + P , it releases those energies which are used to help fuel all of the body’s activities Figure 2.30: Structure of Adenosine Triphosphate (ATP). (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at Objective 1: Describe the components of a typical cell. See OpenStax A&P pages 87–88; Fig. 3.13. A generalized view of the cell is a composite of many different cells in the body. No single cell includes all of the features of the generalized cell. For ease of study, the cell can be divided into three principal parts: Plasma (cell) membrane Cytoplasm: Cytosol Organelles (except for the nucleus) Nucleus Figure 3.13: A Generalized Human Cell. While this image is not indicative of any one particular human cell, it is an example of a cell containing the primary organelles and internal structures. Objective 2: Describe the structure and function of the plasma membrane. See OpenStax A&P pages 87–90; Figs. 3.2, 3.3, 3.4. Structure: double layers of phospholipid molecules that are arranged tail to tail with many protein molecules as well as cholesterol dispersed within them. Their arrangements is known as fluid mosaic model since most of membrane lipids and many proteins move within the bilayer and they are not rigidly locked in place. Some of it could be due to the combination of saturated and unsaturated fatty acid tails as well as the presence of many other molecules dispersed within them. But anyhow the basis of the membrane is the two stacked layers of phospholipids/ lipid bilayer. Cholesterol stabilizes the membrane and maintain its fluidity. The almost tightly packed phospholipids and the hydrophobic inner portion of the bilayer make them selectively permeable only material that meet a certain criterion can pass through without any aid - The surfaces of the membrane are hydrophilic due to the polar phosphate heads. The internal portion of the membrane is hydrophobic due to the nonpolar fatty acid tails. - A combination of saturated and unsaturated fatty acid tails adds to the fluidity of tails that are constantly in motion - amphipathic molecules are those that have a hydrophilic region and hydrophobic regions - the phospholipid heads face outwards so for one layer they face the exterior and for the other layer they face the interior of cells  since they are polar then they are attracted to the intracellular fluid and the other ones are attracted to the extracellular fluid which is the fluid environment outside of the cell Functions of the plasma membrane: Flexible sturdy barrier that contains the cell cytoplasm Control and regulate concentration of substances inside the cell Control what goes in and out of the cell Two types of proteins are associated with cell membrane: Integral protein: embedded in the membrane and are firmly inserted into and extend across the lipid bilayer. Most of these proteins are glycoproteins, which serve as channels (pores), transporters (carriers), receptors (recognition sites), or enzymes. channel proteins are an example. They selectively allow particular materials such as some ions to pass in or out of the cell cell recognition proteins: mark a cell’s identity so they can be recognized by other cells receptors: these are types of recognition proteins that can selectively bind a specific molecule outside the cell and this binding induces a chemical reaction within the cell glycoproteins: integral protein with carbohydrate molecules attached to it and extend into extracellular matrix these aid in cell recognition Peripheral proteins: found loosely bound on inner or outer surface of the lipid bilayer and they also could be attached to the internal or external surface of an integral protein these usually perform a specific function for the cell serving as enzymes or cytoskeletal anchors. Figure 3.4: The Cell Membrane. The cell membrane is a phospholipid bilayer containing many different molecular components, including proteins and cholesterol, some with carbohydrate groups attached. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) glycocalyx Objective 3: Describe membrane transport, and compare and contrast the different processes. See OpenStax A&P pages 90–96; Figs. 3.5, 3.6. Intracellular fluid (ICF) is located inside the cell, and extracellular fluid (ECF) is located outside the cell. The types of extracellular fluid include the following: Interstitial fluid : extracellular fluid that is not contained within blood vessels Plasma: blood Lymph Solutes are substances dissolved in a solvent. A concentration gradient is the difference in the concentrations of a substance between two areas (e.g. the amount of sodium ions in extracellular fluid compared to the amount of sodium ions in intracellular fluid). Transport processes are classified according to two criteria: Active or passive Passive transport: type of transport across the membrane that does not require input of cellular energy. Cells use three passive transport processes: Two of them are non-mediated diffusion through the lipid bilayer and diffusion through a channel One is mediated facilitated diffusion Active transport: type of transport across the membrane that does require input of cellular energy. Vesicular transport involves the formation of membrane-surrounded vesicles to move materials into or out of the cell by endocytosis or exocytosis. Objective 4: Define and contrast the terms diffusion, osmosis, isotonic, hypertonic, hypotonic, and facilitated diffusion. See OpenStax A&P pages 91–94; Figs. 3.5, 3.6, 3.7, 3.8. Diffusion is the random mixing of particles that occurs in a solution because of the kinetic energy of the particles movement of particles from an area of higher concentration to an area of lower concentration. Diffusion is influenced by the following factors: Steepness of the concentration gradient Temperature Size or mass of the diffusing substance Surface area Diffusion distance Molecules or ions move spontaneously from regions where they are in higher concentrations toward regions where they are in lower concentrations (i.e., down a concentration gradient), which produces a state of equilibrium. uncharged, nonpolar, hydrophobic molecules such as respiratory gases, some lipids, small alcohols, and ammonia can diffuse right across the lipid bilayer with no need of mediation. This bilayer allows gas exchange, absorption of some nutrients, and excretion of some wastes. Very small polar molecules such as water can cross via simple diffusion due to their small size. Most membrane channels are ion channels, which allow the passage of small, inorganic, hydrophilic ions. Ion channels are selective and specific and may be gated or open all the time. Facilitated diffusion is the process used for those substances that cannot cross through the lipid bilayer due to their size, charge, and polarity with the aid of a membrane protein/transporter that undergoes a conformational change. In facilitated diffusion, a solute bind to a specific transporter on one side of the membrane and is released on the other side after the transporter undergoes a conformational change This is the process by which glucose enters the cell by glucose transporter to be used to make ATP glucose is both large and polar How is the movement of materials controlled? / the concept of selectively permeable - Tightly packed phospholipids and their hydrophobic inner portion is the first layer of selectively controlling the movement of material into and out of the cell. The lipid bilayer portion of the allows the following to move through the membrane down their concentration gradient by simple diffusion:  very small, polar molecules such as water and small alcohols  small and uncharged molecules such as respiratory gasses  hydrophobic molecules such as lipids - but the following cannot pass the lipid bilayer  large polar molecules  hydrophilic molecules  charged molecules in any size  repel by hydrophobic tails  ions in any size  repel by hydrophobic tails  macromolecules - Transmembrane proteins such as channels and carriers increase permeability of membrane to molecules that cannot cross the lipid bilayer portion. These for example could be certain small inorganic ions that pass-through ion channels which can be either open or gated. - Macromolecules pass through the plasma membrane by vesicular transport. Osmosis is the diffusion of water molecules through a selectively permeable membrane down its concentration gradient. Water moves from a region of lower solute concentration to a region of higher solute concentration. The tonicity of a solution relates to the concentration of solutes outside of the cell relative to the inside of a cell, and how the solution influences the shape of body cells. In an isotonic solution, the concentration of solutes outside of the cell is the same as that inside the cell. In such a solution, red blood cells maintain their normal shape. In a hypotonic solution, the concentration of solutes outside of the cell is less than that inside the cell. In such a solution red blood cells swell and undergo hemolysis. In a hypertonic solution, the concentration of solutes outside of the cell is greater than that inside the cell. In such a solution, red blood cells shrink and undergo crenation. Objective 5: Define the terms active transport, endocytosis, and exocytosis. See OpenStax A&P pages 94–95; Fig. 3.9. Active transport is an energy-requiring process moves solutes such as ions, amino acids, and monosaccharides against a concentration gradient. In active transport, which pumps a substance across a plasma membrane against its concentration gradient, the energy derived from adenosine triphosphate (ATP) changes the shape of a transporter protein. In active transport, the energy stored in the form of a sodium or hydrogen ion concentration gradient is used to drive other substances against their own concentration gradients. Last paragraphs of page 94 Figure 3.9: Sodium-Potassium Pump. The sodium-potassium pump is found in many cell (plasma) membranes. Powered by ATP, the pump moves sodium and potassium ions in opposite directions, each against its concentration gradient. In a single cycle of the pump for each ATP that is used, three sodium ions are exported out, and two potassium ions are imported into, the cell. Most common type of active transport use proteins that are called pumps that use the energy from ATP to pump ions or molecules usually against their concentration gradient. Sodium potassium pump Na/K ATPase transports sodium out of cell while moving potassium into the cell. Usually found in nerve cells to maintain electrical gradient across the cell membranes which is difference in electrical charge across a space. In the process of endocytosis, molecules or particles that are too large to enter the cell by diffusion or active transport are brought into a vesicle formed from a section of the cell membrane. In the process of exocytosis, membrane-enclosed structures called secretory vesicles, which form inside the cell, fuse with the cell membrane and release their contents into the extracellular fluid. Objective 6: Distinguish between endocytosis, pinocytosis, phagocytosis, and exocytosis. See OpenStax A&P pages 94–97; Figs. 3.9, 3.10, 3.11, 3.12. A vesicle is a small membranous sac that forms by budding off from a cell membrane. Other forms of active transport that do no involve membrane carriers: Two types of vesicular transport are: Endocytosis is a form of active transport. In this process molecules or particles that are too large to enter the cell by diffusion or active transport are brought into a vesicle formed from a section of the cell membrane ingesting of material by enclosing them in a portion of the cell membrane. This portion of membrane then pinches off and becomes an independent intracellular vesicle. These often bring materials that need to be broken down or digested by cells. Exocytosis membrane-enclosed structures called secretory vesicles, which form inside the cell, fuse with the cell membrane and release their contents into the extracellular fluid substances manufactured by cells that needs to be secreted are packaged within the membrane bound secretory vesicles such as digestive enzymes The three main types of endocytosis are: Phagocytosis : endocytosis of large particles Pinocytosis (bulk-phase endocytosis) : endocytosis of fluids containing dissolved substances These two bring in large portions of extracellular materials but they not highly selective in what they bring in Receptor-mediated endocytosis: endocytosis of a portion of cell membrane that contains many receptors that are specific for a substance. Once the ligand binds the receptors, the cell endocytose the portion of the membrane containing the receptor-ligand complexes. Iron is bound to transferrin in blood. Then these bind the transferrin receptors on RBC s and then the cell endocytose the whole receptor-ligand complex as iron is required by hemoglobin. Figure 3.10: Three Forms of Endocytosis. Endocytosis is a form of active transport in which a cell envelopes extracellular materials using its cell membrane. (a) In phagocytosis, which is relatively non-selective, the cell takes in large particles. (b) In pinocytosis, the cell takes in small solutes suspended in fluid. (c) In receptor-mediated endocytosis, the cell invaginates only after binding a specific ligand. (From OpenStax College, Anatomy & Physiology. Used under a CC BY 4.0 license. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction.) Objective 7: Define cytoplasm and cytosol. See OpenStax A&P pages 97–98; Fig. 3.13. The cytoplasm consists of cytosol and organelles the internal material between the cell membrane and the nucleus of cell contains water-based semifluid, cytosol, organelles, cellular solutes and suspended materials Cytosol, the intracellular fluid, is the semifluid portion of cytoplasm that contains inclusions and dissolved solutes. Cytosol is composed mostly of water, plus proteins, carbohydrates, lipids, and inorganic substances. The chemicals in cytosol are either in solution or in a colloidal (suspended) form. Functionally, cytosol is the medium in which many metabolic reactions occur. Provides the fluid medium necessary for biochemical reactions Organelles: membrane bound bodies in the cell and each perform a unique function Nucleus: cell’s central organelle that contains the cell’s DNA Objective 8: Describe the structure and function of each cellular organelle. See OpenStax A&P pages 98–104; Figs. 3.13, 3.14, 3.15, 3.16, 3.17, 3.18. The Cytoskeleton The cytoskeleton is a network of several kinds of fibrous proteins and protein filaments that extend throughout the cytoplasm and provide a structural framework and integrity for the cell. They are also critical for cell motility, cell reproduction and transportation of substances within the cell. The cytoskeleton consists of microfilaments, intermediate filaments, and microtubules. Most microfilaments are composed of actin, and function in movement and mechanical support. Thinnest. Actins form chains to form actin filaments and twisted chain of actin filaments make the actin fibers that are a large component of muscle tissue. In muscle cells, these long actin strands are called thin filaments and are pulled by thick filaments of myosin protein to contract the cell. Also, during cell division, actin filaments with myosin create the cleavage furrow which split the cell in the middle and forms two new cells from the original cell. Intermediate filaments are composed of several different proteins, and function in support and helping to anchor organelles s