BIG STUDY GUIDE

Chapter 1 

Major Themes of Anatomy and Physiology 

1. Know the definitions of anatomy and physiology. 

Anatomy is the structure of living organisms while physiology is how they function  

II. Homeostasis 

1. Know the definition of homeostasis. 

Maintenance of relatively constant internal environment   

2. Be able to provide examples of factors that must be maintained via homeostasis. 

Body temp, glucose, blood pressure, pH, Oxygen levels, blood volume, waste levels, CO2 levels  

3. Understand the difference between negative feedback and positive feedback. 

1. Understand why negative feedback is much more common than positive feedback. 

Because negative feedback loops happen more often as they are the way we maintain homeostasis   

4. Understand that the physiological processes that occur in our bodies (which we will be studying for the rest of the semester) ARE the mechanisms that are employed to accomplish negative feedback and, therefore, homeostasis. (Some physiological processes, such as reproduction, are not directly related to maintaining homeostasis, but most are.) 

Chapter 3 

Cellular Form and Function 

I. Plasma Membrane  

A. Know the basic functions of the plasma membrane. 

Defines the boundaries of the cell, controls interactions with other cells, controls movement of materials in and out of the cell  

B. Membrane Proteins 

1. Know the various types of membrane proteins. 

A) Receptors – bind chemical messengers such as hormones. Usually specific for one kind of chemical messenger. 

b) Enzymes – you know what enzymes are. These are just membrane bound enzymes. 

c) Channel Proteins – understand the difference between leak channels and gated channels. Know the three kinds of gated channels and what causes them to open/close. 

leak channels are always open  

Gated channels may be ligand-gated, voltage gated or mechanically gated   

d) Carrier Proteins – proteins that help to move molecules across the plasma membrane. They may help molecules diffuse down their concentration gradient (facilitated diffusion), or they may move molecules against their concentration gradient (active transport). If they work against a concentration gradient, they are called pumps they require ATP.  

e) Cell-Identity Markers – understand the importance of these glycoproteins (see also above in section V.D.) 

contribute to glycocalyx, which enables the body to distinguish its own health cells from transplanted tissues, invading organisms and diseased cells 

f) Cell-Adhesion Molecules – understand what these do. 

Allows cells to adhere to one another and to extracellular material  

II. Membrane Transport 

1. Know what is meant by the term selectively permeable. 

Plasma membrane can act as both a barrier and a pathway between the cytosol and the extracellular fluid  

2. Understand the difference between passive and active transport (which one requires energy?) 

Passive is osmosis, diffusion and facilitated diffusion  

Active transport is also vesicular transport and requires energy   

3. Diffusion – Know the definition. Understand this concept, and know the factors that might affect the rate of diffusion through a membrane. 

Movement of molecules from an area of high concentration to an area of low concentration.  

Can be affected by temperature, molecular weight of the molecule, steepness of the concentration gradient, membrane permeability to that molecule.  

4. Osmosis – Know the definition. Understand this concept, and know the name of the type of pore that water moves through. 

The movement of water from one side of a membrane to the other.   

The type of pore water moves through is called aquaporins  

5. Understand what the terms isotonic, hypertonic, and hypotonic mean, and be able to tell me the direction of water movement (osmosis) if a cell is placed in a solution exhibiting any of these conditions. 

Isotonic is when the solute concentration outside the cell is equal to the solute concentration inside the cell. There is no net movement of water, water moves in and out equally 

Hypertonic is when the solute concentration outside the cell is higher than inside the cell. Water moves out of the cell toward the higher solute concentration 

Hypotonic is when the solute concentration outside the cell is lower than inside the cell. Water moves into the cell, toward the higher solute concentration  

6. Know the definitions of facilitated diffusion and active transport, and know the differences between the two.  

Facilitated diffusion is a carrier-mediated transport of a solute through a membrane down its concentration gradient, no energy is required  

Active transport is a carrier protein that moves a substance across a cell membrane against its concentration gradient, energy provided by ATP is required.  

7. Know what the sodium-potassium pump is. Know which ions it pumps, and in which direction (into or out of the cell). Know the functions of this pump, and understand why it is so important.  

About one-half of all calories, you use each day go toward the actions of this pump. The functions of this pump are to regulate cell volume, maintain membrane potential and produce heat 

8. Vesicular Transport - Know the difference between endocytosis and exocytosis. 

Endocytosis = cell takes in materials by engulfing them in vesicles.  

Exocytosis = cell expels materials by fusing vesicles with the membrane.  

Endocytosis included phagocytosis, pinocytosis and receptor-mediated endocytosis  

Chapter 12 

Nervous Tissue 

9. Understand that both the nervous system and the endocrine system are involved in regulating and coordinating our physiology. 

2. Understand the three broad descriptions of what the nervous system has to do: 

1. Receive information about the internal and external environments – this is done by the sensory neurons in the afferent division of the peripheral nervous system. 

2. Process the information and determine if a response is necessary – this is done by the interneurons of the central nervous system.  

3. Send commands to carry out responses – this is done by the motor neurons in the efferent division of the peripheral nervous system. 

3. Know the difference between the central nervous system and the peripheral nervous system. 

CNS = Brain + Spinal Cord → The command center. 

PNS = Nerves outside CNS → The communication network that links the CNS to the rest of the body. 

4. Know about the structure of neurons. Know the definitions and functions/importance of each of the following: soma, dendrites, axon, axon hillock, myelin sheath, node of Ranvier, internode, axon terminal. Be able to identify each of these on a diagram.  

Soma- central part of the neuron containing the nucleus and organelles, integrates incoming signals and maintains cell health 

Dendrites- branch-like extensions from the soma, receive signals from other neurons and transmit them toward the soma 

Axon- long, single extensions from the soma, conducts electrical impulses (action potentials) away from the cell body 

Axon Hillock- cone-shaped region where the axon originates from the soma, initiates the action potential, decision point foe firing 

Myelin Sheath- Fatty, insulating layer covering the axon, Increases speed of impulse conduction along the axon 

Node of Ranvier- Gaps between segments of the myelin sheath, allows saltatory conduction-nerve impulses jump from node to node for faster signaling 

Internode- The myelinated segment between two nodes of Ranvier, provides insulation and allows for rapid signal transmission 

Axon Terminal- End branches of the axon, release neurotransmitters into the synapse to communicate with the next cell 

5. Myelin – Understand the function of myelin.  

It’s a spiral layer of insulation around a nerve fiber, formed by oligodendrocytes in the CNS and by Schwann cells in the PNS 

6. Know the factors that affect the speed of conduction along nerves. 

Diameter of the fiber and presence or absence of myelin 

7. Electrical Potentials 

1. Understand what the terms electrical potential, electrical current, polarized, and resting membrane potential mean.  

Electrical potential is the difference in the concentration of charged particles between two points. Measured as voltage 

Electrical current is the flow of charged particles from one point to another 

Polarized is when things have an electrical potential. Living cell are polarized  

Resting membrane potential is the charge difference across the plasma membrane of a cell at rest 

2. Know that the RMP of neurons is -70 mV. Know that this means that the inside of the cell is more negative.  

RMP of neuron is -70mV 

3. Understand that, even though we have some diffusion of K+ out of the cell and some diffusion of Na+ into the cell, there is still, overwhelmingly, more Na+ on the outside of the cell compared to inside and more K+ inside the cell than outside the cell. 

4. Know the terms depolarization and hyperpolarization. 

Depolarization 

Hyperpolarization 

8. Electrical Signals  

1. Understand what a local potential is and where on the neuron they will occur.  

Carry the signal from the dendrite and around the cell body 

2. Understand what an action potential is and where on the neuron they will occur. Know the steps involved in an action potential. Know that an electrical signal along an axon is the result of successive axon potentials occurring down the length of the axon, each triggering one another as they occur. 

3. Understand how the transmission of electrical signals along successive neurons involves alternating usage of local potentials and action potentials.   

Local potentials start the process by responding to stimuli 

Action potential carry the signal down the axon 

Each neuron uses local potential to initiate an action potential 

This pattern allows for signal transmission across entire neural pathway 

9. Signal Conduction 

1. Know how signals are conducted down myelinated axons vs. unmyelinated axons.  

Unmyelinated fibers are continuous conduction 

Myelinated fibers are saltatory conduction 

10. Synapses 

1. Know what a synapse is. 

The area where two cells come together 

2. Know the structure of a synapse, including the definitions/importance of the following: Presynaptic Neuron, Postsynaptic Neuron, Synaptic Cleft, Axon Terminal, Synaptic Vesicles, Neurotransmitter, Neurotransmitter Receptor. Be able to identify each of these on a diagram.  

Presynaptic Neuron is a sending neuron, carries the action potential to the synapse and releases neurotransmitters from its axon terminal 

Axon terminal is at the end of the axon, contains synaptic vesicle filled with neurotransmitters. 

Synaptic Vesicles are small membrane-bound sacs inside the axon terminal 

Neurotransmitter is a chemical messenger, released vy the presynaptic neuron 

Synaptic cleft is the tiny gap between the presynaptic and postsynaptic neuron 

Postsynaptic Neuron is a receiving neuron, has neurotransmitter receptors on its membrane 

Neurotransmitter receptors is proteins on the postsynaptic membrane, bond specific neurotransmitters 

3. Know what a neurotransmitter is.  

A neurotransmitter is a chemical messenger that allows neurons to communicate with each other or with other types of cells 

4. Know the steps involved in synaptic transmission in an excitatory cholinergic synapse. 

5. Know how neurotransmitters can be disposed of to cause cessation of their signal. 

Reuptake: Neurotransmitter reabsorbed into presynaptic neuron. 

Enzymatic Degradation: Neurotransmitter broken down by enzymes. 

Diffusion: Neurotransmitter diffuses away from the synaptic cleft. 

Chapter 13 

The Spinal Cord, Spinal Nerves, and Somatic Reflexes 

10. Somatic Reflexes 

1. Know the definition of a reflex. 

Quick, involuntary stereotyped reactions of glands or muscles to stimulation   

2. Know that reflexes involving skeletal muscle are called somatic reflexes. 

Reflexes involving skeletal muscles are called somatic reflexes 

3. Know the path of a typical somatic reflex arc. 

Somatic receptors in skin sense an input of some kind, afferent nerve fibers carry sensory info from receptor to the spinal cord. Pathway moves through an integrating center; efferent nerve fibers carry motor impulses to the muscles. Effectors carry out the response   

4. Know what muscle spindles are. Know where they are located. Know about their structure. Know what they do.  

They are embedded in the muscle 

Chapter 15 

The Autonomic Nervous System and Visceral Reflexes 

1. Understand that the autonomic nervous system (ANS) is one of the two divisions of the efferent (motor) nervous system and that it functions in regulating the activities of glands, cardiac muscle and smooth muscle. (The other division of the efferent nervous system is the somatic motor division, which controls skeletal muscle contractions.) 

II. Understand that this is an involuntary system. 

The Autonomic Nervous system is an involuntary system 

III. Understand that glands, cardiac muscle, and smooth muscle do not need input from the ANS to function but rather to adjust their activity. For example the heart will continue to beat without input from the ANS, but the rate and strength of heart beats will be adjusted by the ANS.  

IV. Know that the ANS can be divided into sympathetic and parasympathetic divisions.  

1. The sympathetic division is associated with physical activity, stress, or fight-or-flight situations, while the parasympathetic division is associated with times of calmness and rest.  

2. Many organs will receive both sympathetic and parasympathetic input (known as dual innervation), and in most cases the two divisions will have opposing (antagonistic) effects on the target tissue.  

3. In some cases, organs will only receive input from the sympathetic division. In these cases, an enhancement of signals through sympathetic pathways will enhance activity in the gland/muscle, while a reduction or elimination of signals through sympathetic pathways will decrease activity in the gland/muscle. 

Chapter 16  

Sense Organs 

1. Know the definition of a sensory receptor. Understand that some receptors are simply nerve endings, while others are specialized cells that are adjacent to afferent neurons.  

A sensory receptor is any structure specialized to detect stimulus  

2. Know that the function of sensory receptors is to convert a stimulus into electrical signals. Know the name for that process.  

Transduction is the process when a sensory receptor converts a physical or chemical stimulus into an electrical signal 

3. Classification of Receptors – Know how receptors can be categorized according to stimulus modality (e.g. photoreceptors, chemoreceptors, etc.). 

Thermoreceptors- heat and cold  

Photoreceptors- light  

Nociceptors – pain  

Chemoreceptors- chemicals (odors, tastes, body fluid composition)   

Mechanoreceptors- physical deformation caused by vibration, touch, pressure, stretch, or tension  

Chapter 11  

Muscular Tissue 

1. Know that skeletal muscle is voluntary. Know why we see striations in skeletal muscle.  

The striations are due to an overlapping arrangement of internal contractile proteins 

2. Know the details about the structure of skeletal muscle fibers. Know what the following are: sarcoplasm, myofibrils, sarcoplasmic reticulum, sarcolemma, T tubules, myoglobin, glycogen. 

Sarcoplasm- cytoplasm, large amount of glycogen as well as myoglobin  

Myofibrils- long string of preoteins called myofilaments   

Sarcoplasmic reticulum- control calcium ions necessary for muscle contraction   

Sarcolemma- plasma membrane- has t-tubes  

T tubules- transverse tubules  

Myoglobin- oxygen-binding protein  

Glycogen- oxygen-binding protein  

3. Know the names of the two major kinds of myofilaments. Be able to describe the structure of thick filaments and thin filaments.  

Thick filaments – many molecules of the protein myosin  

Thin Filaments – two intertwined strands of actin  

4. Striations – Know what the Z lines are and what is anchored to them. Know what a sarcomere is. Understand that the Z lines are pulled closer to one another during contraction.  

The z-lines provide anchorage for the thin filaments  

z-lines are pulled closer to one another during contraption  

5. What do we call the neurons that innervate skeletal muscle cells? Know what a motor unit is.  

Somatic motor neurons   

A motor neuron will include 200 muscle fibers  

VI. Neuromuscular Junctions 

1. Know what a neuromuscular junction is. 

Point where a neuron meets a target call is called a synapse   

2. Know about and be able to label the following on a diagram: axon terminal, synaptic cleft, junctional folds, synaptic vesicles, acetylcholine receptors, motor nerve fiber, muscle cell.  

-Axon Terminal is at the end of motor neuron’s axon where neurotransmitters are released, contains synaptic vesicles filled with acetylcholine 

-Synaptic cleft is the small gap between the axon terminal and the muscle cell membrane, neurotransmitters cross this gap to bind to receptors on the muscle cells 

-Junctional Folds is the specialized folds in the sarcolemma at the neuromuscular junction, increase the surface area for acetylcholine receptors and facilite neurotransmitter binding 

-Synaptic Vesicles are small sacs within the axon terminal containing the neurotransmitter acetylcholine 

-Acetylcholine receptors are proteins located on the junctional folds of the sarcolemma 

-Motor nerve fiber is the nerve fiber that extends from the central nervous system to the muscle, carrying electrical signals to the muscle cell 

-Muscle cell is the muscle fiber that recives the signal from the motor neuron, triggering contractions,  

3. Know which neurotransmitter is secreted onto skeletal muscle. 

Acetylcholine (ACh)  

4. Know what acetylcholinesterase is and what it does.  

Breaks down the ACh after stimulation of the muscle has occurred  

VII. Contraction of Muscle Fibers 

1. Know the four major phases of contraction. 

1)Excitation  

2)Excitation-Contraction Coupling  

3)Contraction  

4)Relaxation   

B. Know (and understand) the steps involved in each of the phases.  

Excitation  

• Nerve signals arrive at axon terminal and voltage-gated Ca++ channels are opened to allow Ca++ into the neuron  

• Ca++ stimulate synaptic vesicles to release ACh into synaptic cleft  

• ACh diffuses across the cleft and binds to ACh receptors on the sarcolemma  

• Receptors are ligand-gated ion channels are opened to allow Na+ into the muscle fiber. Leads to spreading of electrical signals along the surface of the muscle fiber  

Excitation-Contraction Coupling   

• Wave of electrical signal spread out across the sarcolemma from the neuromuscular junction and entered T tubes  

• Electrical signals in the T tubules open voltage-gated Ca++ channels in the sarcoplasmic reticulum such that Ca++ diffuses from the sarcoplasmic reticulum into the cytosol  

• Calcium binds to troponin of the thin filaments  

• The troponin-tropomyosin complex changes shape and exposes the active sites on the actin filaments, making them available to bind to myosin heads 

Contraction 

• Hydrolysis of ATP to ADP + P_i activation and cocking of myosin head 

• Formation of myosin-actin cross-bridges 

• Power stroke, sliding of thin filament over thick filament 

• Binding of new ATP, breaking of cross-bridge 

Relaxation 

• Nerve signals stop arriving at the neuromuscular junction, so the axon terminal stops releasing Ach 

• Acetylcholinesterase breaks down any Ach still in the synaptic cleft 

• Ca++ is reabsorbed into the sarcoplasmic reticulum 

• As Ca++ levels fall in the cytoplasm, Ca++ is released from troponin 

• Tropomyosin moves back into position to clock the active sites in actin  

Chapter 17  

The Endocrine System 

1. Understand that both the nervous system and the endocrine system regulate and coordinate the activities of our bodies. Understand how they are complementary. 

They coordinate closely through the hypothalamus, which is part of the brain (nervous system) and controls the pituitary gland (endocrine system). 

The nervous system can trigger endocrine responses (e.g., stress response: nervous system activates adrenal glands via hypothalamus). 

The endocrine system can influence the nervous system (e.g., hormones like thyroid hormone affect brain development and mood). 

2. Know what hormones are and how they are transported.  

Hormones are chemical messengers   

Transported by bloodstream from source to target tissues   

Sources include individual cells, glandular tissue, or nervous tissue  

Endocrine system – glands, tissues, and cells that secrete hormones   

3. Know the other methods of cell-to-cell communication. 

Neurotransmitters- secreted by neurons and bind to receptors on adjacent cells  

Paracrine messengers- secreted by one cell and diffuse to adjacent cells, where they bind to receptors and cause change   

4. Know the differences between endocrine glands and exocrine glands.  

Endocrine glands- don't utilize ducts, and secrete their materials into the bloodstream   

Exocrine glands- secrete their materials vis ducts either on to the surface of their body or into the digestive tract   

5. Hypothalamus and Pituitary Gland 

1. Know about the anatomy of the hypothalamus and the pituitary gland. Hypothalamus - Small, located at the base of the brain  

Pituitary gland- suspended from the floor of the hypothalamus by a stalk called the infundibulum  

2. Know how the hypothalamus and posterior pituitary are related both structurally and functionally. 

Structurally: The posterior pituitary is an extension of the hypothalamus. 

Functionally: The hypothalamus makes the hormones, and the posterior pituitary releases them into the blood. 

3. Know how the hypothalamus and the anterior pituitary are related both structurally and functionally.  

Structurally: Connected by blood vessels (hypophyseal portal system), not neurons. 

Functionally: The hypothalamus controls the anterior pituitary by secreting regulatory hormones that direct its activity. 

4. Know the two hypothalamic hormones that get secreted via the posterior pituitary.  

1. Know the functions of oxytocin.  

Uterine contractions during birth 

Promotes milk ejection during breastfeeding 

2. Know the functions of ADH. 

Regulates water balance by increasing water reabsorption in the kidneys 

Helps maintain blood pressure by constricting blood vessels at high concentration 

5. Know the names of the hypothalamic hormones that are released solely to affect the activity of the anterior pituitary. Know what effect each has on the anterior pituitary.  

Thyrotropin-Releasing hormone (TRH) stimulates release of TSH nd prolactin 

Corticotropin-Releasing hormone (CRH) stimulates release of ACTH 

GnRH (Gonadotropin-Releasing Hormone) stimulates LH and FSH 

GHRH (Growth Hormone0releasing hormone) stimulates the release of growth hormone 

GHIH (growth Hormone-Inhibiting Hormone) Inhibits release of GHJ and TSH 

PIH (Prolactin-Inhibiting Hormone) Inhibits release of Prolactin 

6. Know the names of the hormones that are released from the anterior pituitary. Know the functions of each of these hormones, and, where applicable, know the tissues these hormones target.   

Follicle-Stimulating Hormone- In ovaries, stimulate ovarian sex hormones, caused development of the follicles (hold the egg) In men it stimulates sperm  

Luteinizing Hormone- In females, stimulates ovulation (and Corpus luteum) In males, causes secretion of testosterone (together these hormones are called gonadotropins)  

Thyroid Stimulation Hormone-   

Adrenocorticotropic Hormone-   

Prolactin-   

Growth Hormone-   

6. Prolactin – Know the functions as provided. 

PRL   

Milk production and mammary gland growth and development  

Causes parental behaviors in multiple species   

Affects hair growth and sebaceous gland activity  

7. Thyroid Hormone – Know the functions as provided. 

Largest gland to have a fully endocrine function  

Located adjacent to the trachea below the larynx, it has a bi-lobed shape  

Composed mostly of follicles, which consist of follicle cells surrounding a fluid-filled core that contains, mostly, a protein called thyroglobulin (a protein that is the structural precursor to thyroid hormone)  

Thyroid hormone consists of two tyrosine residues that are combined. Either three of four iodines are attached to form triiodothyroninr (T₃) or tetraiodothyronine (T₄) Together they are called thyroid hormone  

VIII. Adrenal Glands 

1. Glucocorticoids – Know the functions of glucocorticoids. 

stimulate fat and protein catabolism, stimulate gluconeogenesis (formation of new glucose), increase glucose level in the blood. Are released from the adrenal cortex in response to ACTH. Often release during times of stress 

2. Aldosterone – Know the functions of aldosterone. Know how its release is regulated.  

Called a mineralocorticoid because it helps to regulate the levels of electrolytes  

Stimulates the kidney to retain sodium, helps maintain blood volume and blood pressure  

Release of aldosterone is under the control of the renin/angiotensin system.   

8. Pancreatic Islets 

1. Know what the islets of Langerhans are. 

Scattered in the exocrine tissue there are clusters of cells called the islets of Langerhans  

These calls secrete several hormones, including glucagon and insulin  

2. Know when glucagon is released and what its functions are.  

Released between meals after the carbohydrates, fats and proteins from our previous meal have been moved into our tissues. Makes sure that glucose levels in the blood don't get too low  

Causes glycogenolysis (breakdown of glycogen into glucose) and gluconeogenesis (formation of glucose from fats and proteins) Bothe serve to provide glucose to maintain glucose levels in the blood  

3. Know when insulin is released and what its functions are. 

Secreted during and immediately following meals. It targets the liver, skeletal muscles and adipose tissue.   

Stimulates cells to absorb glucose, fatty acids, and amino acids either to store then or to metabolize them for energy. (promotes the synthesis of glycogen, fat and proteins and enhances cellular growth and differentiation)  

11. Endocrine Disorders 

1. Know the terms hyposecretion and hypersecretion.  

Hyposecretion- inadequate hormone release   

Hypersecretion- excessive hormone release  

2. Thyroid Gland Disorders 

1. Know what a goiter is. Know why it develops if iodine is not available. 

Thyroid hormone cannot be synthesized, so there is not negative feedback on the production of TSH from the anterior pituitary   

2. Hashimoto’s Disease – Know cause, know symptoms. 

Antibodies attack the thyroid gland and decrease the ability to produce thyroid hormone  

Fatigue, weight gain, cold intolerance, dry skin, hair thinning, constipation, depression, goiter, slow heart rate, muscle aches, memory problems  

3. Grave’s Disease – Know cause, know symptoms. 

Antibodies that bind to the TSH receptor on the thyroid gland and cause overstimulation of the thyroid gland  

Goiter, elevated metabolic rate, nervousness, weight loss, abnormal sweating, and bulging on the eyes  

3. Diabetes Mellitus 

1. Know the difference between Type I and Type II. 

Type I – lack of production of insulin. Genetically predisposed, if they become infected by certain viruses, autoimmune responses may destroy insulin-producing calls. Accounts for 5/10% of cases in the United States. Doses of insulin are effective  

Type II – due to insulin resistance, maybe due to genetic mutation that fucks up your insulin receptors or antibodies or insulin in general. Can also be die to fat fucks (obesity)   

Chapter 19 

The Circulatory System: Heart 

1. Know about, understand, and be able to explain the cardiac conduction system. 

1)SA nodes fire  

2)excitation spreads through atrial myocardium   

3)AV node fires  

4)excitation spreads down AV bundle  

5)subendocardial conducting network distributes excitation through ventricular myocardium  

2. Know what the terms systole and diastole mean.  

Systole- contraction   

Diastole- relaxation  

3. Understand and be able to explain why cells in the SA node have an inherent rhythmicity to the production of electrical signals. 

The cells of the SA node are autorhythmic   

They do not have a stable resting membrane potential  

The cells in the sinoatrial (SA) node have inherent rhythmicity in the production of electrical signals due to their unique structure and ion channel activity. This property allows the SA node to function as the natural pacemaker of the heart.  

4. Know the steps involved when action potentials occur in cardiac muscle cells. Know the significance of the calcium plateau and the long refractory period. 

1)voltage-gates Na+ channels open 

2)Na+ inflow depolarizes the membrane and triggers the opening of still more Na+ channels, creating a positive feedback cycle and a rapidlt rising membrane voltage 

3)NA+ channels close when the cell depolarizes 

4)Ca2+ entering through slow Ca2+ channel prolongs depolarization of membrane, creating a plateau. Falls slightly because of some K+ leakage, but most K+ challens remain closed 

5)Ca+ channels close and Ca2+ is transported out of cell. K+ channels pen and rapid K+ outflow returns membrane to its resting potential 

5. Electrocardiogram – Know what the different parts of the ECG are called, and know how they relate to the activity of the heart. 

Electrical activity of the heart 

P wave- atrial depolarization, contraction, systole 

QRS complex- ventricular depolarization, contraction, systole 

T wave- ventricular repolarization, relax, diastole 

6. Cardiac Output 

1. Know what cardiac output is, and know the two factors can affect cardiac output. 

The amount of blood ejected by each ventricle in one minute   

The two factors that can affect it are heart rate and Stroke volume 

2. Know what bradycardia and tachycardia are.  

Bradycardia- persistent resting adult heart rate lower than 60 beats/min. Common during sleep and in endurance trained athletes  

Tachycardia- a persistent resting adult heart rate above 100 beats/min. May occur due to stress, stimulants, and heart disease  

3. Know the Frank-Starling law. 

Stroke volume is proportional to end-diastolic volume. In other words, the ventricles will eject as much blood as they receive  

Chapter 20 

The Circulatory System: Blood Vessels and Circulation 

1. Know the three main categories of blood vessels and the main function of each. 

Arteries- carry blood away from the heart  

Veins- carry blood to the heart  

Capillaries- connect the smallest arteries to the smallest veins   

2. Know what a capillary bed is, and know how flow to particular capillaries can be regulated.  

Exchange of materials with the tissues occurs only in the capillaries and in some of the smallest veins 

3. Blood Pressure 

1. Know what systolic pressure and diastolic pressure are.  

Systolic- peak pressure recorded during ventricular systole  

Diastolic- minimum arterial pressure, measured during ventricular diastole 

2. Know what pulse pressure is.  

Systolic pressure- diastolic pressure = pulse pressur 

3. Know what mean arterial pressure is and how it can be calculated.  

It is another measure if pressure  

MAP= diastolic pressure + 1/3 pulse pressure  

4. Know how gravity can affect blood pressure.  

In a standing person, MAP is about 62 mm Hg in arteries of the head and about 180 mm Hg in arteries of the ankle  

Blood pressure increased the lower you go in the body and decreased the higher in the body you are  

5. Know that blood pressure is determined by cardiac output, blood volume, and resistance to flow.  

4. Regulation of Blood Pressure and Flow - Know how aldosterone, angiotensin II, and antidiuretic hormone might affect blood pressure.  

Aldosterone- promotes sodium and water retention in the kidneys  

Angiotensin II – causes vasoconstriction  

Antidiuretic- promotes water retention, but it will also cause vasoconstriction  

5. Venous Return 

1. Know the definition of venous return. 

The flow back to the heart is called venous return  

2. Know the five mechanisms that assist with venous return. 

Pressure gradient- pressure falls as we move from venules to the venae cavae. Promotes flow towards the heart  

Gravity- at least from the head and neck  

Skeletal muscle pump- contractions of muscles and presence of valves pushes blood in one direction  

Thoracic pump- when you inhale, the thoracic pressure drops, while at the same time the diaphragm moves downward to increase abdominal pressure. This moves blood towards the cavity  

Cardiac suction- suction from the empty atria draws blood in.  

Chapter 22 

The Respiratory System 

1. Know what alveoli are and that they are the site of gas exchange.  

Within the lungs, air flows down a dead-end path from the bronchi through bronchioles to alveoli. The alveoli are the site of gas exchange between the air and the blood  

2.  Pulmonary Ventilation – Know definition, know what a respiratory cycle is, and know, in a general sense, why air flows in and out. Know the muscles that drive respiration. 

Ventilation consists of a repetitive cycle of inspiration and expiration, one complete breath cycle is called a respiratory cycle  

Air will flow in and out due to variations in pressure in the thoracic cavity caused by changes a volume change in the thoracic cavity   

Diaphragm and the intercostal muscles   

3. Understand how the various pressures are related to airflow.  

Air flows in when alveolar pressure < atmospheric pressure. 

 Air flows out when alveolar pressure > atmospheric pressure.  

Negative intrapleural pressure keeps lungs inflated and responsive to thoracic volume changes. 

4. Resistance to Airflow 

1. Know the two factors that can affect resistance to airflow. 

 Air way diameter  

Airway length and viscosity of air  

2. Understand the role of pulmonary surfactant in overcoming alveolar surface tension to allow for greater compliance. 

Pulmonary surfactant disrupts the hydrogen bonds and reduces surface tension  

3. Know what infant respiratory distress syndrome is. 

Mostly seen in premies  

Insufficient surfactant production   

Rapid breathing, grunting, nasal flaring, low oxygen levels  

V. Know that movements of gases into and out of the blood are driven by differences in partial 

pressures of those gases. (Know what a partial pressure is.) 

Partial pressure is the pressure a single gas in a mixture would exert if it were alone in the space. 

It determines how gases move from high to low partial pressure though diffusion 

VI. Oxygen Transport – Know the two ways that oxygen is carried and the relative amounts 

associated with each. Know what the utilization coefficient refers to.  

98.5% in the hemoglobin, rest dissolves in the blood plasma   

Hemoglobin is called oxyhemoglobin if it’s carrying oxygen or deoxyhemoglobin if it’s not  

Utilization coefficient= percentage of oxygen that is released from hemoglobin at the systemic capillaries   

VII. Carbon Dioxide Transport - Know the three ways that carbon dioxide is carried and the 

relative amounts associated with each. Know the details associated with carbon dioxide 

loading and oxygen unloading, and understand how the exchanges of those two gases are related to one another.  

90% reacts with water to form carbonic acid  

5% is bound to hemoglobin  

5% is dissolved in the blood  

Bicarbonate gets pumped out of the RBC in exchange for a chloride ion. This is called the chloride shift. The hydrogen ion binds to hemoglobin and promotes the release of oxygen 

VIII. Know what acidosis and alkalosis are, and know (and understand) how we can adjust the  

pH through respiration. This involves knowing the chemical reaction for when carbon 

dioxide reacts with water.  

Acidosis = blood pH is lower than 7.35  

Fix this by hyperventilating, thus driving off caron dioxide, shift the carbonic acid to the left  

Alkalosis = blood pH is greater than 7.45  

Can fix this by hypoventilating, allows for the accumulation of carbon dioxide, this drives the same reaction to the right