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Framework 1: Introduction to physiology Objectives: 1.) Identify the different levels of organization within the body. a. The different levels of organization within the body are: i. Atoms: the basic unit of matter ii. Molecules: atoms bound together iii. Cells: basic unit of life iv. Tissues: multiple cells v. Organs: multiple tissues vi. Organ systems: multiple organs vii. Organism: all organ systems. 2.) Name the physiological systems of the body and identify their major functions a. Circulatory system: includes the heart, blood vessels, and blood. This system is important in the transport of materials between cells and the body. b. Digestive system: this is the stomach, liver, pancreas, and intestine. It is involved in conversion of food into particles that can be transported into the body; elimination of some waste. i. Exposed to the external environment, c. Endocrine system: thyroid gland, adrenal gland. Important in coordination of body function through synthesis and release of regulatory molecules d. Immune system: thymus, spleen, lymph nodes: defense against foreign invaders e. Integumentary: skin. Protection from the external environment. f. Muscoskeletal: skeletal muscles, bones. Involved in support and movement g. Nervous: brain, spinal cord. Coordination of body functions through electrical signals and release of regulatory molecules. h. Reproductive: ovaries, uterus and testes. Perpetuation of the species i. Exposed to the external environment. i. Respiratory: lungs and airways. Used for exchange of oxygen and carbon dioxide between the internal and external environment i. Exposed to the external environment j. Urinary: kidneys and bladder. Used for maintenance of water and solutes in the internal environment and for waste removal i. Exposed to the external environment 3.) Define and be able to identify intracellular fluid, extracellular fluid, internal environment and external environment. a. Intracellular fluid: this is the fluid that is within cells b. Extracellular fluid (ECF): the internal fluid that surrounds the cells. i. This can be further subdivided into the plasma and interstitial fluid. c. The internal environment: this is the environment in which the cells live in ECF d. The external environment: this is the environment the body lives in and this would be the atmosphere. 4.) Define homeostasis and be able to identify examples of parameters that are controlled by homeostatic responses

a. Homeostasis: the ability of the body to maintain a relatively constant internal environment. i. There are many things in our body that are in a stable: body temperature, heart rate, and blood pressure. b. Homeostasis depends on the law of mass and balance, this says that if the body is to remain constant, and gain, must be off set by an equal loss. i. Examples of these things are: water, oxygen, CO2, salts and H+ ions (pH). ii. Note that the load refers to the amount of something in the body (sodium load). c. Homeostasis however, does not mean equilibrium: equilibrium would be saying that the composition in both compartments; intracellular and extracellular fluid, are identical. This is not the case. 5.) Compare and contrast local and reflex control homeostatic responses i. In their simplest form, all control centers have three components: an input signal, a controller or integrating center and an output signal that creates a response. b. Local control: this is the simplest form of control and is restricted to the to the tissue or cell involved. So in this form a relatively isolated change occurs in the tissue. A nearby cell or groups of cells sense the change in the immediate vicinity and responds, usually by releasing a chemical. This response is restricted to where the region where the change took place. i. Ex.) when oxygen concentration in tissues decrease cells lining the small blood vessels that bring blood to the area sense lower oxygen concentration and respond by secreting a signal. The signal molecule then diffuses to a nearby muscles in the blood vessel wall, bringing them a message to relax. Relaxation of the muscle widens (dilates) the blood vessel, and this increases the blood flow into the tissue and brings more oxygen. c. Reflex control: this is any long-distance pathway that uses the nervous system, endocrine system or both. This can be broken down into two parts: a response loop and a feedback loop. Just like local control, the response loop has the three components. i. What happens Is that the input side of the response loop starts with a stimulus – this is a change that occurs when a regulated variable such as temperature, moves out of its desirable range. Is the sensor is activated by the stimulus, it sends an input signal to the integrating centre. The integrating centre then evaluates the information coming from the sensor and initiates an output signal directs a target to carry out a response. ii. Stimulus  sensor  input signal  integrating centre  output signal  target  response.

1. Note that in mammals the integrating centre is generally the nervous system or the endocrine system. 6.) Distinguish between negative and positive feedback and be able to identify physiological examples of each a. Negative feedback: this is the pathway in which the response opposes or removes the signal. These are pathways that stabilize the regulated variable and thus aid the system in maintain homeostasis. i. In the aquarium example: the heater warms the water (response) and removes the stimulus (low water temperature). With loss of the stimulus for the pathway, the response loop shuts off. 1. Example of this is body temperature: if we get too cold we can put a jacket on to remove the stimulus. b. Positive feedback loop: the response in this case however reinforces the stimulus rather than decreasing or removing it. In this system, the response sends the regulated variable even farther from its set value. This type of feedback requires some outside factor to shut it off. i. Example: the hormonal control of uterine contractions during childbirth. When the baby Is ready to be delivered it drops lower in the uterus and begins to put pressure on the cervix. The opening of the uterus. Sensory signals from the cervix to the brain cause release of the hormone oxytocin, which causes the uterus to contract and push the baby’s head even harder against the cervix, further stretching it. This increase in stretch causes more oxytocin release and this causes more contractions that push the baby harder against the cervix. The cycle continues until the baby is delivered. 7.) Describe the function of the set point. a. Set point: this is the optimum value for a regulated variable. Framework 2 – introduction to physiology Objectives: A.) Atoms and molecules: 1.) Name the chemical elements represented by the symbols: C, H, O, N, Ca, K, Na, I, P, Mg, Cl, Fe a. C: carbon b. H: hydrogen c. O: oxygen d. N: nitrogen e. Ca: calcium f. K: potassium g. Na: sodium h. I: iodine i. P: phosphorus j. Mg: magnesium

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k. Cl: chlorine l. Fe: iron Differentiate between the following terms: atom, molecule, ion, anion, cation, isotope a. Atom: the smallest particle of an element. These have no charge i. In the centre of the atom are the neutrons that have no charge and protons that have a positive charge. In orbitals outside the atom there are electrons that have negative charges. ii. Note that an atom that loses an electron or gains on becomes an ion of the same element iii. If the atom loses a proton it becomes a different element iv. The atomic mass of an atom is calculated by: the number of protons plus the number of neutrons. v. The atomic number of an atom is the number of protons. b. Molecule: two or more atoms linked together by sharing electrons c. Ion: an atom with a net negative or net positive charge due to the loss or gain of an electron. d. Cation: positively charged ions e. Anion: negative charged ions f. Isotope: atoms of the same element that have different numbers of neutrons. Describe the three types of non-covalent bonds a. Ionic: a bond between two ions that are attracted to each other as they have opposite charges. Weak attractive forces between hydrogens and other atoms, especially nitrogen and oxygen. b. Hydrogen bonds: c. Van der Waals forces: weak attractive forces between 2 polar molecules or a polar molecule and an ion. Describe the covalent bonds and differentiate between polar and nonpolar molecules a. Covalent bond: this is when two atoms share electrons in the outermost energy level. i. Note that this bond is very strong and generally needs cellular energy to be broken b. Non polar covalent bonds: when the two atoms share the electrons equally c. Polar covalent bonds: this is unequal sharing of the electrons between two atoms: this results in small region negative and positive charges i. Example of this is water (H2O) oxygen likes the electrons more than hydrogen and will pull them closer to him resulting in oxygen having a slight negative charge and hydrogen having a slight positive charge. Solutions Define the term solution, solute, solvent, solubility, hydrophobic, hydrophilic a. Solution: solute dissolved in solvent b. Solute: substance dissolved in liquid c. Solvent: name for the liquid d. Solubility: a measure of how easy it is for a molecule to dissolve in a solvent.

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e. Hydrophilic: means water loving. Ionic bonds are polar and will dissolved in water. f. Hydrophobic: these are water fearing molecules that are nonpolar and will not dissolve in water. g. Amphipathic: molecules that are part hydrophobic and part hydrophilic. They have polar and nonpolar portions. Define molarity and mole. Know the concentration of a solution is often given as molarity a. Molarity: solution concentration expressed as moles of solute per litre of solution. b. Moles: atoms, ions, or molecules of a substance. (6.02 x 1023) Define acid and base, differentiate between a strong acid and weak acid. Explain the concept oh pH. a. Acids: adds H+ to the solution b. Base: decreases the number of H+ in solution. i. pH is calculated by the negative log of the concentration. ii. pH of 7 is neutral iii. pH > 7 alkaline (base) iv. pH < 7 is acidic. c. Note the range in the ECF is between 7.35 and 7.45 d. When there are more H+ the more acidic and when there are less H+ the more basic Biomolecules Identify the either basic characteristics of biomolecules, carbs, lipids (fats), proteins, and nucleotides. a. Carbohydrates: these are the most abundant and are long chains of sugar molecules (CHO). i. There are things like monosaccharides: which is a single sugar: glucose, fructose, galactose. ii. There are disaccharides which are two sugars together: maltose (glucose + glucose), sucrose (glucose, fructose), and lactose (glucose, galactose). iii. There are polysaccharides which are long chains of sugar: glycogen, starch, cellulose. 1. An important polysaccharide in our body is glycogen which is polymers of glucose. 2. We can see that a polysaccharide in plants is cellulose that is polymers of starch. We as humans do not have the enzyme to degrade this polysaccharide. b. Lipids: these are the most diverse and are nonpolar so they do not dissolve in water. i. A triglyceride is a lipid that is composed of: a glycerol and three fatty acids. This is generally found in adipose tissue and the liver. ii. 90% of body lipids are triglycerides.

iii. These lipids can be very diverse as the hydrogen bonds that make up these fats can either have single or double bonds that is going to alter the property of the fat. 1. The fat is said to be saturated if there are no double bonds and it is solid at room temperature. 2. The fat is said to be unsaturated if there are several double bonds in the fatty acid chain that makes it more of a liquid. a. Note that saturation refers to the amount of “fullness” of hydrogen in the fatty acid. iv. Another form of a lipid is a phospholipid which is composed of a glycerol backbone and 2 fatty acids and a phosphate. These are generally found in the cell membrane. v. We can also find lipid-related molecules such as: steroids that are going to be hormones and eicosanoids: these are regulators of things like clot formation, inflammation, etc. c. Proteins i. These are the most versatile. ii. Amino acids are the building blocks of proteins and there are 20 of them. That means there are lots of combinations in which these amino acids can line up and effect the protein. iii. All amino acids have a carboxyl group (-COOH), an amino group, (-NH2), and a hydrogen attached to the same carbon. The fourth bond of the carbon attaches to the variable “R” group. iv. There are essential amino acids: these are ones that we need from our diet and they can not by synthesized by us v. Non-essential: these are amino acids that can be synthesized by the body. vi. These proteins can have various structures: 1. Primary: this is the long chain of amino acids that are joined together by a peptide bond 2. Secondary: covalent bonds between Amino acids are created 3. Tertiary: this is the 3D shape of the protein 4. Quaternary: multiple proteins combine together by non-covalent bonds. vii. These can do a lot in the body such as: enzymes, membrane transporters, signal molecules, receptors, binding proteins, regulatory proteins, immunoglobins. d. Nucleotides i. These can be found in DNA, and RNA as nucleotide polymers. They are used for genetic information storage. ii. When they are composed of a base, phosphate, and sugar. iii. When they are single they are involved in energy capture and transfer (ATP, ADP, NAD, FAD)

iv. They can also be used for cell communication (cAMP) when they are alone. Framework 3 – Introduction to physiology Objectives A. Cell membranes a. Cells are the basic functional unit of life. They do things like take in oxygen and nutrients, eliminate wastes, communication, and growth and repair and reproduce. b. Human cells are compartmentalized: in the cell there is the cell membrane, the nucleus and the cytoplasm: i. Within the cytoplasm there is: cytosol (the liquid), inclusions, organelles, and protein fibres. 1. Inclusions are particles of insoluble material; some are stored nutrients. Others are responsible for specific cell functioning. 2. Protein fibres: these are the cells internal support system or cytoskeleton. 1.) Describe the fluid mosaic model of the cell membrane a. This states that the membrane is not static but is rather moving and the mosaic portion is saying that both leaflets of the membrane are not symmetric. 2.) Describe the four main functions of cell membrane a. One of the main functions of the cell membrane is for compartmentalization (physical isolation): it separates the intracellular fluid from the extra cellular fluid. the phospholipids are what produce this compartmentalization and they are organized into what is called a lipid bilayer. These phospholipids are amphipathic meaning that their heads are polar and like the fluid of ICF and ECF and their tails are non-polar and hydrophobic. b. Exchange regulation i. The cell membrane controls the entry of ions, and nutrients into the cell, elimination of cellular wastes, and the release of products from the cell. c. Communication i. The cell membrane contains proteins that enable the cell to recognize and respond to molecules or changes in its external environment. Any alternation in the cell membrane may affect the cells activities. d. Structural support. i. Proteins in the cell membrane hold the cytoskeleton, the cells interior structural scaffolding in place, to maintain cell shape. Membrane proteins also create specialized junctions between cells. 1. The cell membrane is composed of variable composition of lipids, proteins, and CHO. B.) cell structures

1.) list and describe the basic cell structures – including the plasma membrane, nucleus, cytoplasm, and cytosol, and organelles.  Nucleus: stores the genetic information and controls gene expression, cell division and production of RNA. This is referred to as the control centre. o This structure has a nuclear envelope: this is a double membrane that separates the nucleus from the cytoplasm. o Nucleolus: contains the DNA that controls the synthesis of RNA o Chromatin: is the DNA and protein o Nuclear pores: regulate the movement of material into and out of the nucleus. 3.) list the major structures and functions of the following organelles: mitochondria, smooth and rough ER, Golgi, lysosomes, peroxisomes, ribosomes, and microfilaments and microtubules a. rough endoplasmic reticulum: this is a network of interconnected membrane tubes that are a continuation of the outer nuclear membrane. This rough ER has a granular appearance due to rows of ribosomes dotting its cytoplasmic surface. i. Ribosomes are involved in protein synthesis. b. Smooth ER: these lack ribosomes and appear as smooth membrane tubes. This part of the ER synthesizes lipids, and in some cells, concentrates and stores calcium ions (sarcoplasmic reticulum). It is also the site of cholesterol to steroid conversion. c. Golgi apparatus: this consists of a series of hollow curved sacs called cisternae stacked on top of one another and surrounded by vesicles. This is involved in protein modification and packaging. These transport vesicles from the ER. d. Mitochondria: these are organelles that have two membranes that actually produces two compartments. The inner matrix is surrounded by a membrane that folds into leaflets called cristae. The intermembrane space which lies between the two membranes, plays an important role In ATP production. e. Lyososmes: these are small spherical storage vesicles that contain powerful digestive enzymes. These are the ones that break down old organelles and bacteria in the cell f. Peroxisomes: these are small storage vesicles that contain enzymes to breakdown fatty acids and foreign toxins. g. Microfilaments: these are part of the cells cytoskeleton and form a network just underneath the cell membrane h. Microtubules: these are also part of the cells cytoskeleton and are the largest cytoskeleton fibre. i. Both of these microtubules and microfilaments are involved in: contractile proteins, intracellular storage, and movement of cilia and flagella. C.) tissues 1.) identify the specialized types of cell-cell junctions and give their main functions  Communicating: gap junctions: these are the simplest and thy allow direct and rapid cell to cell communication through cytoplasmic bridges. Cylinder proteins called connexions

are able to interlock to create passageways that look like hollow rivets with narrow channels through their centres. The channels open and close, regulation the movement of small molecules and ions through them.  Occluding: tight junctions: these are ones that restrict the movement of material between the cells the link. In tight junctions, the cell membranes of adjacent cells partly fuse together with the help of proteins called claudins and occludins.  Anchoring: desmosomes: these attach to intermediate filaments of the cytoskeleton. They are the strongest. The protein they use to hold the two membranes together are cadherins. These are important in tissues where they undergo a lot of stretching and twisting. 2.) identify the four tissue types and describe their characteristics a. connective tissue: this is used for structural support and can be found: adipose, blood, cartilage, ligaments, and tendons. It has an extensive extracellular matrix. b. muscle tissue: has the ability to contract and produce force and movement i. skeletal ii. cardiac iii. smooth c. neural tissue: used for control and communication i. glial cells: these are support cells for neurons d. epithelia tissue: this is to protect the internal environment and regulate exchange between the internal and external environment. i. The cells for this tissue are held together by desmosomes. This is things like the skin and cells that are lining cavities that are exposed to the external environment. 3.) identify and name the 5 types of epithelia a. protective: prevent exchange between the internal and external environment and protect areas subject to mechanical and chemical stres...