Exam No. 2 - Chapters 5, Part 2; 6; and 11

Lymphocytes

-- 20-35% of wbcs -- specific acquired immunity -- T cells and B cells

Effect of NEFA on Euglycemia

-- NEFAs ---> via acute (chronic) ---> pancreas -- Fat cells (via glucose uptake) ---> NEFAs ---> via gluconeogenesis ---> liver -- NEFAs ---> via glucose uptake ---> muscle

Intervenous Infusion

-- NaCl --> 0.15 Osm unit + 0.15 Osm unit = 0.3m (same as 0.3m glucose solution) -- both 0.3 Osm glucose and 0.15 saline (have same osmolality and osmotic pressure so blood cells will be unaffected) -- ex. if a membrane separates a 0.3m glucose solution and a 0.15m NaCl solution, there will be no net movement of water = isotonic (because equal # of solute particles on either side) -- **remember molality (m) directly correlates with Osm units (1m = 1 Osm)

Diffusion of Gases: Simply No Barrier

-- O2 from extracellular environment into tissue cells -- CO2 from tissue cells into extracellular environment -- this is true except for lungs - it is the opposite. Oxygen is leaving lung cells (to oxygenate blood) while carbon dioxide is entering lung cells (to be exhaled).

Innate Immune System

-- Physical Barriers -- Bloodbourne --> Phagocytes --> Death of Dangerous Organisms

Prohormones

-- are inactive hormones that must be cut and spliced together to be active -- example: insulin is produced from proinsulin in pancreatic beta-cells (proinsulin is derived from preproinsulin)

Prehormones

-- are inactive prohormones that must be modified within their target cells -- to become activated, target cells must modify it -- T4 must be modified to T3

Molality

-- considers the ratio of solute to water -- 1molal (Osm) solutions take the molecular weight i grams dissolved in exactly 1kg (1L) water -- the amount of water never changes, so you can compare solute concentrations to predict the direction of osmosis -- does not depend on the chemistry of the solute, but on how many particles are present in the solution -- dumping 1 mole into a flask already containing 1L of water (so the total can be more than 1L - due to displacement of the water)

Isotonic

-- equal tension so osmosis will not occur -- equal inside and outside of rbc

Cell Signaling: Integration

-- estimated that the 200 different cell types in the human body may have as many as 30,000 different types of receptors

Nonself

-- foreign material -- foreign invader

Nonspecific Chemical Defenses - GI Tract

-- hydrochloric acid in stomach (inhibitory and destructive to many microbes) -- digestive juices and bile of intestines (destructive to many microbes)

Hypersensitivity Reactions

-- immediate hypersensitivity -- antibody-mediated -- immune complex -- T-cell-mediated

Herd Immunity

-- immune individuals will not harbor it, reducing the occurrence of pathogens -- benefit: less likely that a nonimmunized person will encounter the pathogen -- problems with re-emerging infections because people are not getting vaccinated (being more protected)

Adipose Tissue

-- major hormones: leptin (appetite); resistin -- primary target organs: hypothalamus -- primary effects: suppresses appetite

Leukocyte Subtypes

-- neutrophils -- eosinophils -- basophils -- monocytes -- lymphocytes

Hypo-osmotic

-- one solution has a lower solute concentration and therefore a lower osmotic pressure than the other solution

Opsonization

-- process by which a pathogen is marked for ingestion and destruction by a phagocyte

Interferon

-- produced in response to viruses, RNA, immune products and various antigens 1) bind to cell surfaces and induce changes in genetic expression 2) stimulate phagocytes

Adrenergic

-- receptors for epinephrine and norepinephrine

Nonspecific Chemical Defenses - Urogenital System

-- semen contains an antimicrobial chemical -- vagina has acidic pH (maintained by labctobacilli) (yeast infection is a secondary infection because of the antibiotics)

Nonspecific Chemical Defenses

-- skin -- secretions -- excretions -- GI tract -- urogenital system

Allergic Reactions

-- skin contact -- injection -- ingestion -- inhalation

Mean Diffusion Time

-- the average time it takes for a solute to diffuse (less distance, faster time)

Types of Fat Tissue

-- white: most triglycerides sotred this way, (f) energy storage -- brown: (f) themogenesis (heat production)

Adrenal glands

= cortisol = fight or flight (chronic stress can lead to...)

Amygdala

= emotional center of brain

Non-Esterified Fatty Acids (NEFA)

???

???

A friend, wanting to lose weight, eliminates all fat from her diet. How would this help her to lose weight? Could she possibly gain weight on this diet? How? Discuss the health consequences of such a diet.

Compare the four chemical classes of hormones with reference to hormones within each class.

Amine hormones, derived from the amino acids tyrosine and tryptophan, are the hormones secreted by the adrenal medulla, thyroid, and pineal. Polypeptides include antidiuretic hormone and others that are shorter than about 100 amino acids, whereas hormones that are polypeptide chains longer than that - such as growth hormone, are considered to be proteins. Glycoprotein hormones, including FSH and LH, are composed of proteins and carbohydrates. Steroid hormones are derived from the lipid cholesterol and include the sex steroids such as testosterone and estradiol as well as cortisol from the adrenal cortex.

b) Decreased transport.

An amino acid is transported into cells via secondary active transport. Administration of a drug that blocks the activity of the Na/K ATP-ase would have what effect on the transportation of this amino acid into the cell? a) Increased transport. b) Decreased transport. c) No change in transport.

E. GH - up

An antibody is injected into an experimental rat. This antibody binds to somatostatin and makes it nonfunctional. The secretion of which hormone will be most affected, and in what direction? (up = increase, down = decrease) A. GH - down B. ACTH - up C. LH - down D. FSH - down E. GH - up F. LH - up G. ACTH - down H. FSH - up

Interstitial fluid (tissue fluid)

Approximately 80% of the extracellular fluid is outside the vascular system and is called _________.

Explain the nature of autocrine regulation. How does it differ from regulation by hormones and neurotransmitters?

Autocrine regulators are chemicals secreted by some cells of an organ that act locally within the organ. They are classified generally as paracrine regulators because they act within the same organ where they are produced. This distinguishes them from neurotransmitters, which must cross a synaptic gap to influence a target cell, and hormones, which must pass through the blood to get to their target cells. Paracrine regulators that act on the same cells or cell type in the organ may also be called autocrine regulators.

???

Brenda experiences muscle pain and fatigue and during an intense workout felt a severe, sharp pain in her left pectoral region. What metabolic pathway is associated with muscle pain and fatigue?

???

Brenda experiences muscle pain and fatigue and during an intense workout felt a severe, sharp pain in her left pectoral region. What serious medical condition could the pain indicate and what produces this condition?

???

Brenda's coach advised her to exercise more gradually. How would this help to reduce her muscle fatigue?

Central Inflammation

Can end up with ____ because of the integrity of the tight junctions and the leaky blood vessels and the blood brain barrier.

A. Bone marrow.

Central tolerance of B lymphocytes to self antigens develops in which compartment? A. Bone marrow. B. Thymus. C. Spleen. D. Lymph nodes.

B. IgD.

Class switching of IgM could yield all of the following except A. IgE. B. IgD. C. IgG. D. IgA.

The extracellular matrix of ordinary connective tissues consists of a ground substance made of water, glycoproteins, and proteoglycans, and protein fibers of collagen and elastin. Matrix metalloproteinase enzymes can degrade the extracellular matrix. These enzymes aid normal processes such as tissue remodeling and the movement of cells through the matrix, but can cause tissue destruction in pathological cases.

Describe the composition of the extracellular matrix and explain the importance of the matrix metalloproteinases.

???

Describe the effect of cyanide on oxidative phosphorylation and on the citric acid cycle. Why is cyanide deadly?

Nerves

Fibers

C. low blood aldosterone levels.

Hypotension (lower than normal blood pressure) accompanied by hyponatremia (decreased plasma sodium levels) and hyperkalemia (increased plasma potassium levels) could be due to A. elevated blood ACTH levels. B. low blood PTH levels. C. low blood aldosterone levels. D. elevated blood thyroxine levels.

1) synergistic = together is better than alone (2 heads are better than 1) 2) permissive = I am allowing whatever to happen (giving permission; yes) 3) antagonistic = no (block) -- hormones only go through the endocrine system

Interactions between hormones produce effects that are what?

b. acetyl CoA.

Intermediates formed during fatty acid metabolism can enter the citric acid cycle as a. keto acids. b. acetyl CoA. c. Krebs cycle acids d. pyruvic acid.

a. fatty acids

Ketone bodies are derived from a. fatty acids b. glycerol c. glucose d. amino acids

E. tolerant.

Lymphocytes that do not respond to self antigen presented by the antigen presenting cells are said to be A. naïve. B. immunoreactive. C. immunogenic. D. activated. E. tolerant.

Pineal Gland

Melatonin

A. kidney B. bone

Parathyroid hormone increases renal Ca2+ reabsorption by acting on the structures labeled A kidney and B bone.

D→B→E→ C→A

Rearrange the following in the correct order: A. Activation of adaptive immunity B. Activation of toll-like receptors C. Cytokines D. Lipopolysaccharide E. Dendritic cells

E→ C→D→B→ A

Rearrange the following in the correct order: A. Extravasation B. Histamine C. Opsonization D. Phagocytosis D. Antigen

E. B and C.

Regulatory T lymphocytes inhibit the activity of A. helper T lymphocytes. B. killer T lymphocytes. C. B lymphocytes. D. A and B. E. B and C. F. A, B and C.

D. Dehydroepiandrostenedione.

Selective destruction of the zona fasciculata of the adrenal cortex would produce a deficiency of which hormone? A. Androstenedione. B. Aldosterone. C. Cortisol. D. Dehydroepiandrostenedione.

Differences between Norepinephrine and Epinephrine

Similarities: -- released by adrenal medulla -- catecholamines (derived from Tyr) -- play roles in stress responses (also alter arterial blood pressure and metabolism) Differences: -- adrenomedullary output is about 80% epi and 20% NE (adrenals mediate epi essentially) -- NE is primarily produced by sympathetic postganglionic neuron fibers (mediated in large part by sympathetic nervous system) -- have different affinities for adrenergic receptors

B

The disruption of the hypothalamo-hypophyseal portal circulation would result in which of the following alterations (up = increase, down = decrease, NC = no change) in circulating levels of hormones? A. IGF-1 - NC; PTH - down; GHRH - NC B. IGF-1 - down; PTH - NC; GHRH - up C. IGF-1 - up; PTH - down; GHRH - up D. IGF-1 - up; PTH - NC; GHRH - down E. IGF-1 - NC; PTH - up; GHRH - down

c) slightly more positive than the equilibrium potential of potassium ion.

The membrane potential of most neurons at rest is a) equal to the equilibrium potential of sodium ion. b) slightly more negative than the equilibrium potential of potassium ion. c) slightly more positive than the equilibrium potential of potassium ion. d) equal to the equilibrium potential of potassium e) slightly more positive than the equilibrium potential of sodium ion.

a) K+

The most important diffusible ion in the establishment of the membrane potential is a) K+ b) Na+ c) Ca2+ d) Cl-

True

True or False Higher solute concentrations increases osmotic pressure?

True

True or False Is simple diffusion down concentration gradient?

True

True or False Nuclear receptor transcriptional activity can be promoted or repressed?

True

True or False? Cells communicate with each other using chemical signals?

Emotions from Olfactory (scent) Neurons, Stressors, and Circadian Rhythms

What activates the hypothalamus? -- since the hypothalamus receives input from higher brain regions, ______ can alter hormone secretion -- at least 26 brain regions and olf

-- tonsils and adenoids -- lymph nodes -- Peyer's patches and appendix -- bone marrow -- thymus -- spleen -- lymph nodes

What are the Immune Organs?

-- recognition -- inflammation -- phagocytosis -- interferon -- complement

What are the actions of the second line of defense?

1) Extracellular Factor (ECF) 2) Receptor 3) Intracellular Mediators 4) Nucleus

What are the cell signally components?

-- innate immunity (rapid response): macrophage = main phagocytic cell -- adaptive response (slow response): B cell, T cell

What are the cells of the immune system (only the ones we need to know)?

-- regulatory molecules released from neurons, endocrine glands, pancreatic beta-cells, wbc, adipocytes, osteocytes, endothelial cells lining blood vessels (all kinds of cell types)

What chemical signals are used to communicate between cells?

???

What effect would a significant increase in saturated fatty acids have on blood flow in narrow blood vessels?

???

What effect would a significant increase in saturated fatty acids have on rbc membrane fluidity? b. blood flow in narrow blood vessels?

-- bind to adrenergic receptors (alpha, beta, etc.) -- alpha1 = smooth muscle contraction (vasoconstriction - increased blood pressure) -- alpha2 = inhibition of transmitter release; smooth muscle contraction (vasodilation) -- beta = heart muscle contraction, smooth muscle relaxation, glycogenolysis (increased glucose level)

What is the difference between norepinephrine and epinephrine?

???

What is the physiological significance of the more than 30,000 different types of receptors for the different cells of the human body?

???

What molecular mechanism may mediate the diversity of the more than 30,000 different types of receptors for the different cells of the human body?

C. Interferon

Which of the following defenses is most likely to be active during a viral infection? A. Inflammation B. Fever C. Interferon D. Complement

a) Primary active transport.

Which of the following has a direct requirement for ATP in order to function properly? a) Primary active transport. b) Secondary active transport. c) Facilitated diffusion. d) Simple diffusion. e) Osmosis.

B. Human chorionic gonadotropin - Ovary.

Which of the following hormone - gland relationships is incorrect? A. Glucagon - Pancreas. B. Human chorionic gonadotropin - Ovary. C. Melatonin - Pineal gland. D. Testosterone - Testis.

A. White blood cells

Which of the following is NOT an example of a first line defense? A. White blood cells B. Lysozyme C. Hydrochloric acid in the stomach D. The sneeze reflex Cilia in the respiratory tract

A. White blood cells

Which of the following is NOT an example of a first line defense? A. White blood cells B. Lysozyme C. Hydrochloric acid in the stomach D. The sneeze reflex E. Cilia in the respiratory tract

d) Potassium.

Which of the following may be transported from the intracellular fluid to the extra-cellular fluid without using cellular energy? a) Proteins. b) Amino acids. c) Sodium. d) Potassium.

d) Pinocytosis.

Which of the following modes of transport is most likely to experience the phenomenon of saturation? a) diffusion. b) Facilitated diffusion. c) Primary active transport. d) Pinocytosis.

a) they are needed to mediate the action of nonpolar regulatory molecules

Which of the following questions regarding second messengers is false? a) they are needed to mediate the action of nonpolar regulatory molecules b) they are released from the plasma membrane into the cytoplasm of cells c) they are produced in response to the binding of regulatory molecules to receptors in the plasma membrane d) they produce the intracellular actions of polar regulatory molecules

a) On activation, the alpha subunit separates from beta and gamma subunits.

Which of the following statements is true about G proteins? a) On activation, the alpha subunit separates from beta and gamma subunits. b) Activation involves binding GDP. c) Interaction with an agonist promotes inactivation of a G protein. d) Activation is reversed when GTP is bound.

e) A and B only

Which of the following will result in an increase in diffusion rate across the membrane? a) Higher concentration gradient. b) Reduced membrane thickness. c) Less surface area. d) All of the above e) A and B only

???

Why is fat the preferred source of stored energy (compared to carbohydrates or protein)?

Adipose Tissue (primarily white for energy)

fatty acids come from where?

Skeletal Muscle

lactic acid and amino acids come from where?

antiport

moving two molecules in opposite direction

Cell Signaling

signals = ligands

The Immune Response

• Activation of the immune response typically begins when a pathogen enters the body. Macrophages that encounter the pathogen ingest, process and display the antigen fragments on their cell surfaces. • Macrophages with antigen fragments displayed on their surfaces are called antigen-presenting cells. An antigen-presenting macrophage interacts with a T-helper cell that can recognize the same antigen. • During the interaction, the macrophage releases a chemical alarm signal called interleukin-1, which stimulates the T-helper cell to secrete interleukin-2. Interleukin-2 causes the proliferation of certain cytotoxic T cells and B cells. • The immune response from this point follows two paths, one using cytotoxic T cells and one using B cells. • Normal cells of the body that become infected can also digest some of the pathogens and display antigen fragments on their cell surfaces. The body makes millions of different types of cytotoxic T cells. • Each type is able to recognize a particular antigen. The cytotoxic T cells that are capable of recognizing the antigen displayed on the surfaces of infected cells bind to the infected cells and produce chemicals that kill the infected cell. • Death of the infected cells results in destruction of the pathogen. B cells also come in millions of different types, each able to recognize a particular antigen. • When B cells become activated by T-helper cells, they differentiate into plasma cells. These plasma cells become antibody-producing factories, flooding the bloodstream with antibodies that can bind to the antigen involved in this infection. • Antibodies bind to the antigen on the surfaces of the pathogens, marking them for destruction by macrophages. • Some of the B cells do not turn into antibody factories, but instead become memory B cells that may survive for several decades. • Because of these memory B cells, the "secondary immune response" to a future infection by the same pathogen is swifter and stronger. • This powerful secondary immune response is what gives "immunity" to some diseases after you have had them once or after you have been vaccinated.

Pathogen Recognition Receptors (PRRs)

-- receptors on wbcs for PAMPs (coastguard)(toll-like receptors)

Granulocytes

-- recruited out of blood and into tissues when needed (Basophil: involved in allergies; scarcest type of WBC)(Eosinophil: attack and destroy large eukaryotic pathogens; secrete ROS, leukotrienes, prostaglandins and cytokines; more numerous in bone marrow than circulation)(Neutrophil: first responder phagocyte; circulate in bloodstream and recruited to site of infection within minutes; 55-90% of circulating WBCs)

Hypothalamus

-- regulates hunger, thirst, sleep and wakefulness plus most of your involuntary mechanisms including body temperature

Thyroid Glands

-- regulates your energy and your metabolism

Promoters (activators, or repressors)

-- regulatory proteins are needed in addition to the steroid hormone -- they bind to the nuclear receptor proteins at specific regions on receptor different from where the steroid hormone binds -- this changes the effect of a given hormone in different cells; may activate or suppress transcription factors -- highly regulated!!

c) a hypertonic solution

Red blood cells crenate in a) a hypotonic solution b) an isotonic solution c) a hypertonic solution

c) Hyposmotic; Isotonic.

Solution A contains 100 mM CaCl2 and 50 mM glucose. Solution B contains 175 mM NaCl. These solutions are seperated by a membrane that is permeable to all solutes except glucose. Which of the following best describes solution A in comparison to solution B? a) Isosmotic; Hypertonic. b) Isosmotic; Isotonic. c) Hyposmotic; Isotonic. d) Hyperosmotic; Isotonic. e) Hyposmotic; Hypotonic.

Dendritic

-- antigen-presenting cells, act as messengers between innate and adaptive immune system (by interacting with T and B-cells)

First Line of Defense

-- any barrier that blocks invasion at the portal of entry -- nonspecific -- skin, mucosal

Thymus

-- contains cells that mature into T lymphocytes and specifically react to viruses, parasites, fungi, foreign tissue, and other antigens -- controls cell-mediated immunity

A recent study published in the Journal of Endocrinology demonstrated that patients suffering from stress-related disorders including post-traumatic stress disorder (PTSD), chronic pain and fatigue syndromes also have low cortisol plasma levels. Cortisol is a well-established hormone involved in generating a stress response. For patients suffering from stress-related disorders, what would you expect their vulnerability to stress to be?

-- PTSD = Low plasma cortisol, increased sensitivity, low hormone level = increased receptors, high hormone level = decreased receptors -- cortisol helps deal with stress and reduces inflammation -- makes more vulnerable -- cortisol receptors increase -- cortisol therapy / vacation / babysitter, etc.

Ketone Bodies

-- a last resort source of energy -- produced when the rate of lipolysis exceeds the rate of fatty acid utilization (during starvation, extreme dieting, diabetes) (the concentration of fatty acids i the blood increases...from white fat) -- if hepatocytes contain sufficient ATP, the acetyl CoA generated from fatty acids through beta-oxidation is converted to ____...so the liver produces ____ (water-soluble molecules that circulate in the blood...so what is their affect on blood pH?) (build-up in the blood can cause ketosis)

Molarity

-- a mole of a compound can be measured as its molecular weight in grams -- 1M (molar) solution is 1 mole in 1 liter solution -- 1M solution Tris = 121.14 g in 1L ultrapure water

Destruction + Elimination (mechanisms of phagocytosis)

-- respiratory burst -- liberation of lactic acid, lysozyme, and nitric oxide

Physical or Anatomical Barriers: First Line of Defense - Skin

-- Skin and mucous membranes of respiratory, urogenital, eyes, and digestive tracts -- outermost layer of skin is composed of epithelial cells compacted, cemented together, and impregnated with keratin; few pathogens can penetrate if intact -- flushing effect of sweat glands -- blinking and tear production -- stomach acid (pH = 2) -- keratin = tight barrier (our own little rain coat) -- if abrasion, punctures, etc. = barrier is compromised -- sweat, tears, stomach acid = contain antibacterial components

Acquired Immune System

-- T-cell immunity (cell-mediated immunity) -- B-cell immunity (humoral immunity) --> Antibodies

Difference between lipids and fatty acids

-- Triacylglycerides (triglycerides) are a subgroup of lipids containing a glycerol headgroup and 3 long fatty acid tails -- a free fatty acid (FFA) is simply a fatty acid tail (long hydrocarbon chain) -- fats pack 9 kcal of energy per gram of fat while both proteins and carbohydrates only offer 4 kcal per gram.

Receptors

-- ______ are proteins

Immune Complex (Hypersensitivity Reactions)

-- antibody-mediated inflammation -- circulating IgG complexes deposited in basement membranes of target organs -- includes some autoimmune diseases -- examples: systemic lupus erythematosus; rheumatoid arthritis; serum sickness; rheumatic fever

Basophils

-- 0.5% of wbcs -- respond to large eukaryotic pathogens and recruit other leukocytes -- contain histamines, prostaglandins, and other chemical mediators of the allergic response

Eosinophils

-- 1-3% of wbcs -- destruction of large eukaryotic pathogens such as worms and fungi -- found in spleen and bone marrow -- contain toxic proteins, inflammatory mediators, and digestive enzymes

Cell Signaling: Transcriptional Activation

-- 2.5 million end products from 1 receptor -- if more, number increased

Complement

-- 26 blood proteins that work together in a signaling cascade to destroy a wide variety of bacteria, viruses and parasites

Monocytes

-- 3-7% of wbcs -- phagocytosis, followed by final differentiation into macrophages and dendritic cells -- secrete several chemicals that moderate the functions of the immune system -- largest wbc -- turn into macrophages - circulate as ____, but once migrate they are targeted to site of infection and burrow down they turn into microphages

Neutrophils

-- 55-90% of wbcs -- general phagocytosis -- life span = 2 days -- 4-10 hrs circulation -- contain digestive enzymes

Self vs. Non-Self and Autoimmunity

-- APC = antigen presenting cell -- TCR = T-cell receptor -- MHC = major histocompatibility complex boils down to major histocompatibility complex (MHC) - molecule that is present on all of our cells. This is how we know whether it's self or non-self (markers for self); this comes into play in a kidney transplant, but immune systems are different, this is where we get organ rejection - small tweaking on MHC receptor that is why they give you immunosuppressant's. Prone to MERSA or c-diff (super infection or primary infection)

Connection between Lipolysis and Beta-Oxidation

-- Adipose Tissue: triglycerides --> via lipolysis --> fatty acids -- Blood: fatty acids -- Muscle: fatty acids --> via beta-oxidation --> acetyl CoA

Phospholipase C System

-- IP3 has receptors on the smooth ER which binds and releases Ca2+ (1. muscle contraction; 2. neurotransmitter release; 3. death - because high levels of Ca2+ isotoxic) = decreased sensitivity -- Smooth ER = intracellular Ca2+ stores -- DAG = Diacylglycerol -- DAG --> PKC --> phosphoralation of target proteins

Immediate Hypersensitivity (Hypersensitivity Reactions)

-- IgE-mediated -- examples: anaphylaxis, allergies such as hay fever, asthma

Antibody-Mediated (Hypersensitivity Reactions)

-- IgG, IgM antibodies act upon cells with complement and cause cell lysis -- includes some autoimmune diseases -- examples: blood group incompatibility, pernicious anemia; myasthemia gravis

Hyperglycemia: pathogenesis

-- Islet alpha and beta cell hormones regulate glucose homeostasis -- healthy: alpha cells secrete glucagon; beta cells secrete insulin -- type 2 diabetes: alpha cells dysfunction: secrete inappropriately high levels of glucagon; fewer beta cells: secrete insufficient levels of insulin

Effects of Extracellular Environment on Cell Mechanisms

-- Outside the cell there is always large fluctuations occurring. In contrast the cell has alterations going on inside the cells. Amplification occurs inside the cell in response to the large fluctuations outside the cells. -- Large EC factors: Heat; Dehydration; Trauma -- Stressors - hypothermia; diabetes; COPD; etc.; Obesity; pH -- Markers = definition -- ** We can't control heat stress (military in full gear, standing in the heat); large external fluctuations = things that you can't control; internal fluctuations and amplification is where you hope that you can get everything under control.

Cell Signaling: Receptors

-- a target cell receives a signal because it has receptor proteins specific to it on the plasma membrane or inside the cell -- lipid soluble (nonpolar) (have a lipid soluble ligand to pass through) (steroid, hormones, thyroid hormone, nitric oxide gas ca penetrate the plasma membrane and interact with receptors inside the cell (b) -- water soluble (large, polar) (must bind extracellular to pass through - extracellular binding domain) (epinephrine, acetylcholine, and insulin bind to receptors on the plasma membrane (a)

Autoimmunity

-- abnormal responses to self Ag (don't recognize yourself and attack yourself)

Hyperthyroidism

-- accelerated growth -- increased activity -- decreased sleep -- intolerance to heat -- normal skin -- excessive perspiration -- rapid pulse -- frequent bowel movements -- increased appetite -- decreased weight -- rapid reflexes -- nervous "emotional" state -- increased T4 levels

Osmosis: clinical case - edema

-- accumulation of fluid in the interstitial fluid (interstitium) -- edema has a multifactorial pathogenesis -- if there is a high solute concentration in the blood (means low water in blood), water will move OUT of tissues and INTO the circulation -- normal solute concentrations within our blood allow water to constantly "fill" or contribute to stable blood volume (albumin typically served this role) -- if solutes happen to get too high and blood volume increases, we typically urinate to remove this excess volume/fluid in an effort to prevent blood pressure from getting too high (due to increased blood volume) -- sometimes there is low solute concentration (which means high water in blood) so water moves OUT of the circulation and INTO tissues - this is why you get observable tissue swelling -- "pitting edema" -- generally, when health is not maintained, vascular integrity is threatened, thereby making blood vessels leaky -- in turn, fluid, electrolytes and proteins move OUT of the circulation and INTO peripheral tissues -- during the clinical condition proteinuria (passing of protein in the urine), edema is commonly observed because you have a state of low "solute" in the blood which means high blood water so water will move DOWN its concentration gradient, into the tissues, thereby causing edema

Third Line of Defense

-- acquired with exposure to foreign substance -- produces protective antibodies and creates memory cells -- specific -- adaptive immune system

Lymph Nodes

-- act as filters to remove debris and antigens and to foster contact with T lymphocytes

Peyer's Patches and Appendix

-- act as filters to remove debris and antigens entering the gastrointestinal tract

Tonsils and Adenoids

-- act as filters to remove debris and antigens entering the respiratory tract

Mechanism of Steroid Hormone Action - Genomic Action

-- activates transcription of target genes -- requires at least 30 minutes to work -- receptors are in the cytoplasm, though some may be in the nucleus (once the hormone binds to the cytoplasmic receptor, the complex translocates to the nucleus) (hormone-receptor complex then binds to the specific hormone-response element of DNA (this activates transcription) (one part of the receptor binds ligand while the other binds to target gene DNA) -- all cells contain same genetic material; how they are different is whether or not they have the receptors or not. You have to have the receptor!!

Spleen

-- acts as a filter to remove debris and antigens and to foster contact with T lymphocytes

Hexokinase

-- adds a phosphate group onto glucose so that it will stay inside a target cell

Pancreas

-- aids in the digestion of protein, fats and carbohydrates -- produces insulin which controls blood sugar levels

Grave's Disease (Disease of the Thyroid)

-- an autoimmune disorder that causes hyperthyroidism, resulting in goiter

Lysozyme

-- an enzyme that hydrolyzes the cell wall of bacteria, in tears

Allergy, Hypersensitivity (Immune Response)

-- an exaggerated, misdirected expression of immune responses to an allergen (antigen) (anaphylactic shock) (hypersensitivity = epi pen)

Glucagon

-- antagonistic to insulin -- secreted by alpha cells when blood glucose levels are low (during fasting) -- purpose is to raise blood glucose levels to a "normal" range 1) through stimulation of glycogenolysis by liver and gluconeogenesis (making glucose); and 2) stimulates lipolysis in an effort to increase available energy (breaking down fat for energy)

TSH (thyroid stimulating hormone)

-- anterior pituitary gland - T3 / T4 -- target tissue: thyroid gland -- actions: stimulates secretion of thyroid hormones -- regulation of secretion: stimulated by TRH (thyrotropin-releasing hormone); inhibited by thyroid hormones

ACTH (adrenocorticotropic hormone)

-- anterior pituitary gland -- target tissue: adrenal cortex -- actions: stimulates secretion of glucocorticoids -- regulation of secretion: stimulated by CRH (corticotropin-relasing hormone); inhibted by glucocorticoids

FSH (follicle-stimulating hormone)

-- anterior pituitary gland -- target tissue: gonads -- actions: promotes gamete production and stimulates estrogen production in females (development of ovarian follicular waves) -- regulation of secretion: stimulated by GnRH (gonadotropin-releasing hormone) released by the hypothalamus; inhibited by sex steroids and inhibin

LH (luteinizing hormone)

-- anterior pituitary gland -- target tissue: gonads -- actions: stimulates sex hormone secretion; ovulation and corpus luteum formation in females; stimulates testosterone secretion in males -- regulation of secretion: stimulated by GnRH released by the hypothalamus; inhibited by sex steroids

PRL (Prolactin)

-- anterior pituitary gland -- target tissue: mammary glands and other sex accessory organs -- actions: promotes milk production in lactating females; additional actions in other organs -- regulation of secretion: inhibited by PIH (prolactin-inhibiting hormone)

GH (growth hormone)

-- anterior pituitary gland -- target tissue: most tissues -- actions: promotes protein synthesis and growth; lipolysis and increased blood glucose -- regulation of secretion: inhibited by somatostatin; stimulated by growth hormone-releasing hormone

Integrins

-- are glycoproteins that extend from the intracellular cytoskeleton, through the plasma membrane and bind to the extracellular matrix (serve as an adhesion molecule connecting cells and their extracellular environment) (serve as relay signals between the intracellular and extracellular environment)

Macrophage

-- are monocytes but once in tissue are called macrophages; phagocyte; second phagocytic cells to appear at site of infection

Lipid Metabolism: Lipogenesis (creating fats)

-- as ATP levels rise after an energy-rich meal, production of ATP is inhibited: 1. glucose enters glycolysis as normal and the resulting pyruvate is converted into acetyl CoA (acetyl CoA does not enter Krebs cycle though)(the acetyl CoA already formed is joined together to produce a variety of lipids, including cholesterol, ketone bodies, and fatty acids 2. fatty acids combine with glycerol to form triglycerides in the adipose tissue and liver (lipogenesis)

Olfactory (Scent) Neurons (activators of the hypothalamus)

-- at least 26 brain regions and _____ scent axons to the GnRH-producing neurons -- example: synchronization of menstrual cycles in groups of females (external response mediating an internal response) (due to phermones)

Cell Signaling: Signaling Modalities

-- autocrine (ex. pancreatic beta cells can secrete cytokines but they have receptors for cytokines - can be released and then bind and decrease insulin production - is counterproductive and self-destructive)

Pemphigus

-- autoimmune disorder that attacks your skin (raw sores and hair falls or gets pulled out) --> give cychlosporin to suppress inflammatory response (can't fight any other infections during this treatment i.e. vaccines) (no immunity)

Cancer

-- both a cause and effect of immune dysfunction

Pancreas

-- both an endocrine and an exocrine gland -- endocrine cells are located in ____ islets (islets of Langerhans) a) alpha cells: glucagon (glucose is gone) - raises blood sugar; b) beta cells: insulin - lowers blood sugar

Lipolysis

-- breaking down fats (triglycerides into fatty acids and glycerol) -- lipase is the enzyme involved 1) fatty acids can then enter the blood as blood-borne energy carriers and be used for energy elsewhere (liver, skeletal muscles and other organs for aerobic respiration - Krebs cycle) (so fatty acids are converted into acetyl CoA which is how the fatty acids enter the Krebs cycle) 2) glycerol in the circulation is taken up by the liver and converted to glucose through gluconeogenesis (benefits of this? ...during exercising or fasting glycerol can serve as an important source of glucose for the liver, a vital organ) -- FFA = free fatty acids -- epinephrine is the primary hormonal stimulator of lipolysis - it activates hormone sensitive lipase. It stimulates lipolysis through binding to beta-adrenergic recepetors and inhibits lipolysis by binding to alpha-adrenergic receptors. Why is insulin a primary inhibitor of lipolysis?

Gabba

-- calms you down

Fatty Acids

-- can be converted into acetyl CoA which can then enter the Krebs cycle -- DIAGRAM (3 long chains which are the 3 fatty acids + glycerol)

Receptors

-- can be on cell surface, plasma membrane, or can be intracellular (typically in the nucleus)

Triglycerides

-- can be used for energy via the same pathways used for the metabolism of pyruvate -- hydrolyzed into glycerol and three fatty acids

Dehydration

-- can increase blood osmolality and therefore osmotic pressure (OP) (because blood becomes more concentrated while total blood volume is reduced) (osmoreceptor neurons in the hypothalamus are stimulated by increased OP...so they shrink due to the increased extracellular osmolality causing: 1) mechanically stimulates them to fire impulses, alerting the person to drink; 2) also promotes water retention so less urination

Active Transport

-- carrier-mediated -- active transport requires energy -- net movement against concentration gradient -- energy (ATP) is provided by carrier proteins (pumps)

Cell Signaling: Paracrine Signaling Type

-- cells within an organ secrete regulatory molecules that diffuse across the extracellular matrix (ECM) to nearby target cells (local, but not touching

Cell Signaling: Gap Junction Type

-- channel proteins between cells that allow the passage of ions and regulatory molecules (very localized) -- cytoplasm must be touching -- intracellular

Aquaporins

-- channels in the membrane during osmosis -- found in the kidneys, eyes, lungs, salivary glands, and the brain

Diffusion of Ions: Required Channels

-- charged ions can pass through ion channels that cross the plasma membrane that may always be open or gated (sodium and potassium; open: diffusion is always occurring; gated: dependent on specific physiological stimuli) -- larger polar molecules can not pass through the membrane by simple diffusion but need special carrier proteins (glucose - glucose transporters, GLUTs) -- like calves (Cav; Kv)

Diapedesis

-- chemokines are released from the cells to bring in the immune cells (landing lights of the injury or infection)(monocytes are going in then they turn to macrophages in the third diagram on this slide) -- migration of cells out of blood vessels into the tissues

Recognition (mechanisms of phagocytosis)

-- chemotaxis and ingestion: phagocytes migrate and recognize PAMPs 1) TLRs (PRRs) --> PAMPs 2) MHC

Biosynthetic Pathway for Steroid Hormones

-- cholesterol = production from food and liver -- have to have cholesterol to produce hormones (corticosterone...)

Intracellular Receptor

-- comes in via the nuclear pores

Solution

-- consists of a solvent (ex. water) and a solute (ex. molecules dissolved in water) -- molecules in a solution are in a constant state of motion -- if there is a concentration difference between two regions, random motion will establish equilibrium via diffusion

Regulation of Blood Osmolality

-- constant osmolality must be maintained or neurons will be damaged...and the brain controls everything

Extracellular Matrix

-- contains protein fibers of collagen and elastin, and a gel-like substance -- protein fibers provide structural support -- collagen contributes to basement membrane -- interstitial fluid is found in this gel-like substance

Bone Marrow

-- contains stem cells for B lymphocytes, which mature and become antibody-producing plasma cells that react to many bacteria, viruses and other antigens -- controls humoral immunity

Pituitary Gland

-- controls all other endocrine glands -- influences growth, metabolism, and regeneration

Stress and the Adrenal Glands: Side Effects

-- cortisol may act on higher brain regions (result: contributes to depression and anxiety and memory loss) -- cortisol may also act on insulin-sensitive tissues (result: by cortisol stimulating the liver to release glucose (through glycogenolysis and gluconeogenesis) and lipolysis (adipose tissue), insulin receptors may become resistant, making it harder to treat people with diabetes -- cortisol can also impact immune function (result: wbcs lose ability to fight infection and it can also promote wbc death) -- cortisol can act on memory and emotion regions of the brain (result: memory loss - cortisol receptors in preforontal cortex, hippocampus - and depression and anxiety - amygdala)

Lipogenesis

-- creating fats (formation of fat) -- primarily occurs in two locations: 1. adipose tissue; and 2. liver (fatty liver disease)

****Second Messengers: cAMP

-- cyclic adenosine monophosphate (cyclic AMP or cAMP) is a common second messenger -- steps to activate: 1) a polar signaling molecule binds to a cell surface receptor; 2) receptor conformational shape changes which activates adenylate cyclase which generates cAMP from ATP; 3) cAMP concentration increases (signal amplification); 4) cAMP activates other enzymes; 5) cell activities change in response signal = recognition second = drives pathways end result = "downstream" is gene regulation / transcription very redundant, many pathways utilize cAMP: 1) first messengers are signals 2) second messenger mediates functional activity of intracellular mediators / relays; second messenger drives intracellular mediators; secons messengers always drive amplification 3) all of the above must occur for a response

Natural Killer Cell

-- cytotoxic lymphocyte critical to innate immune system; cause cytokine release, lysis or apoptosis of infected cells

Immunodeficiency

-- deficiency or loss of immunity

T-Cell-Mediated (Hypersensitivity Reactions)

-- delayed hypersensitivity and cytotoxic reactions in tissues -- examples: infection reactions; contact dermatitis; graft rejection; some types of autoimmunity

Amines

-- derived from the amino acids: tyrosine (Tyr); tryptophan (Trp) -- example: norepinephrine (adrenal medulla) -- example: thyroxine (T4) and triiodothyronine (T3) (both from thyroid gland)

Unique Characteristics of Leukocytes

-- diapedesis -- chemotaxis

Tyrosine Kinase System

-- dimerfication = making both arms come together -- glucose uptake must be 1) insulin receptor activated and 2) glucose by glut (glucose transmitter) -- anabolic = building -- glucose building glycogen

T-Cells

-- do not have antigen-presenting properties, several types; adaptive immune response

Net Diffusion

-- due to random movement -- direction is from high to low solute concentration

Intracellular Mediators

-- enzymes, proteins -- they mediate signal transduction from extracellular all the way down to the nucleus -- ***these pathways work like metabolic pathways in the sense if a process goes wrong the next process won't work either

Adrenal Glands - Adrenal Medulla

-- epinephrine -- norepinephrine

Functions of the Adrenal Medulla

-- epinephrine and norepinephrine 1) activated with sympathetic response (4:1 ratio) 2) have effects similar to sympathetic innervation but last 10 times longer 3) increase cardiac output, respiratory rate, and mental alertness; dilate coronary blood vessels; elevate metabolic rates...why? to fight or flight; maintain energy levels (+glycogenolysis, +lipolysis)

Action of Epinephrine on a Liver Cell

-- epinephrine is one of many hormones that is water soluble (hydrophilic) and therefore unable to cross the hydrophobic plasma membranes of its target cells. Instead, it binds to receptor proteins located in the plasma membrane and does not enter the cell (beta-adrenergic receptor protein) -- when epinephrine binds to beta-adrenergic receptors on the liver cell, G proteins on the inner side of the cell membrane are activated -- each G protein is composed of three subunits and the binding of epinephrine to its receptor protein causes one of the G protein subunits to dissociate from the other two -- the G protein subunit which dissociates from the other carries a GDP, which is replaced by GTP when the subunit is activated -- the activated G protein subunit then diffuses within the plasma membrane until it encounters adenylyl cyclase, a membrane enzyme that is inactive until it interacts with the G protein subunit. When activated by the G protein subunit, adenylyl cyclase catalyzes the formation of cAMP from ATP -- the cAMP formed at the inner surface of the membrane diffuses within the cytoplasm, where it binds to and activates protein kinase-A, an enzyme that adds phosphate groups to specific cellular proteins -- in liver cells, protein kinase-A phosphorylates and thereby activates another enzyme called phosphorylase, which converts glycogen into glucose-6-phosphate. The glucose-6-phosphate is then converted to glucose -- through this multistep mechanism, epinephrine causes the liver to secrete glucose into the blood during the fight-or-flight reaction

Negative Feedback Inhibition of the Anterior Pituitary

-- example: secretion of ACTH is inhibited by cortisol while TSH release is inhibited by thyroxine -- if you remove target glands (like the adrenals, thyroid or gonads) you remove the ability to provide feedback inhibition to the driving source (hypothalamus or anterior pituitary)

Symptoms of Adrenal Fatigue

-- fatigue and lack of energy -- trouble sleeping -- difficulty concentrating -- consistently feeling sick -- weight gain -- mild depression

Memory (Adaptive Immunity)

-- first exposure is a "blip" -- second exposure to an antigen really takes off (this is where allergy shots come into effect)

Pineal Gland

-- function: secretes the hormone melatonin (regulates circadian rhythms - altered during night shifts, mediates seasonal affective disorder - SAD) (produced when it gets dark - due to signaling from retina) -- regulation: by the suprachiasmatic nucleus (SCN) of the hypothalamus through sympathetic neurons (so highly innervated by sympathetic nervous system (SNS) (withdrawal of activation by SCN removes the "stopper" on melatonin release) -- melatonin can act as an anti-inflammatory

Cell Signaling: Endocrine Signaling Type

-- glands secrete hormones into the bloodstream (therefore, can cover long distances to reach target cells) -- extracellular

Adrenal Glands - Adrenal Cortex

-- glucocorticoids (i.e. cortisol) (involved with stressors)(most cells) -- mineralocorticoids (i.e. aldosterone) (involved in water/Na+ balance)(kidneys) -- sex hormones (i.e. testosterone) (involved in reproductive function) (back-up system)

Molarity and Osmosis

-- glucose has a molecular weight of 180g/mole. To make a 1M solution of glucose...dissolve 180g glucose in 1L water -- NaCl has a molecular weight of 58.5g/mole. To make a 1M solution of NaCl...dissolve 58.5g NaCl in 1L water

Circadian Rhythms (activators of the hypothalamus)

-- growth hormone secretion is highest during sleep -- dark / light cycles influence LH surge in egg-laying chickens

Thymus

-- helps build resistence to disease

Tissue Response: Desensitization and Down-Regulation

-- high hormone / chemical concentration receptor -- Desensitization: prolonged exposure to high concentrations of hormone may result in a decreased number of receptors for that hormone (not permanent, but a gray area like genetics; gamma is typically associated with depression) (mediated by down-regulation) -- example: occurs in adipocytes in response to high concentrations of insulin (which leads to insulin resistance) and chronic inflammation down-regulates adrenergic receptors (this is why you cannot depend on pharmacological intervention at the end of the day) -- pulsatile secretion: to avoid desensitization, many hormones are released in spurts (pulses) -- example: prozac - you will eventually need higher dose in a step-like pattern or switch out drugs into a different drug -- example: mental illness drugs you have to be on for the rest of your life and if you remove yourself you will go through withdrawals just like cocaine; these drugs do not cure, they only treat the symptoms (physiological shock) -- example: norepinephrine is a last-ditch effort; this doesn't work when you end up in the hospital for critical problem; you are hosed

Receptor-Hormone Interactions

-- hormones bind to receptors on (polar signals) or in (nonpolar signals) target cells -- highly specific (it has to be because hormones are released into the circulation) -- high binding affinity (affinity: strength with which it binds - like a magnet, want it to stick) -- low capacity (saturating the receptors with hormone molecules) (a small number of receptors can be occupied and still achieve a maximal response due to signal amplification)

Factors Dictating Organ Responsiveness to Hormones

-- hormones may be: 1) antagonistic (opposite effects); 2) synergistic; or 3) permissive (allowing) -- how a cell responds to a hormone depends on the: 1) amount of hormone; 2) effects of other hormones on that tissue; 3) receptors expressed in that target tissue

Polar Hormones (Lipophobic)

-- hormones that use second messengers -- these hormones cannot cross the plasma membrane, so they bind to receptors on the cell surface (which activates an intracellular mediator - secondary messenger)

Tonicity

-- how does a solution affect osmosis? -- higher solute concentrations increase osmotic pressure -- describes the effect a solution has on the osmotic movement of water (isotonic, isosmotic, hypo-osmotic, hypotonic, hypertonic) -- plasma has the same osmolality as a 0.3m glucose or a 0.15m NaCl solution (isosmotic to plasma) -- takes into account the permeability of the membrane to the solutes (if the solutes can cross the membrane, the tonicity will change) -- solutions with a lower solute concentration than the cell are hypo-osmotic and hypotonic (if the solutes are osmotically active) (will pull water into the cell causing the cell to swell and could lyse...hemolysis if blood cells) -- solutions with a higher solute concentration than the cell are hyper-osmotic and hypertonic (if the solutes are osmotically active) (will pull water out of the cell causing the cell to shrivel up and could crenate - become notched or scallop-edged)

Conversion of Glucose into Glycogen and Fat

-- if energy is being delivered to the body faster than it is being consumed (used), excess glucose will enter 2 potential routes for storage: 1) glycogenesis (converting glucose into glycogen molecules) and 2) lipogenesis (converting glucose intermediates into fats) -- When cells have adequate levels of ATP (energy), they down-regulate the respiratory enzymes involved in glycolysis and the Krebs cycle thus the glucose can ONLY enter either glycogenesis or lipogenesis for the purpose of energy storage and NOT complete glycolysis and enter the Krebs cycle and electron transport chain to generate even more ATP (energy).

Extracellular Environment

-- includes everything located outside the cells (nutrients, oxygen, metabolic waste, signaling molecules, hormones, steroids, drugs) -- cells receive NOURISHMENTS from and relase WASTES into the extracellular environment -- cells COMMUNICATE with each other by SECRETING CHEMICAL REGULATORS into the extracellular environment -- all of this occurs ACROSS THE PLASMA MEMBRANE

Stressors (activators of the hypothalamus)

-- increase CRH production as part of the pituitary-adrenal axis (in turn elevates ACTH release and therefore cortisol release) -- external stress (exam, child, family, etc.), external scent --> ACTH --> cortisol release

Salt Intake

-- increases plasma osmolality and OP (osmotic pressure) too -- you get thirsty because the osmoreceptor neurons are shrinking (due to increased osmotic pressure) so this in turn stimulates you to drink as well as ADH release so the kidneys will retain water -- this ends up diluting the salt in an effort to return extracellular sodium concentrations to normal -- but you end up with a higher blood volume due to drinking and water retention

Ovaries

-- influences how your blood circulates and determines your mental vigor and your sex drive (testes in males)

Fever (benefits)

-- inhibits multiplication of temperature-sensitive microorganisms (directly affect bacteria) -- impedes nutrition of bacteria by reducing the available iron (starves them out)(directly affect bacteria) -- increases metabolism and stimulates immune reactions and protective physiological processes (indirectly affects bacteria)

Fever (cellular and physiological mechanisms)

-- initiated by circulating pyrogens which reset the hypothalamus to increase body temperature -- signals muscles to increase heat production (shiver) and vasoconstriction -- exogenous pyrogens - products of infectious agents -- endogenous pyrogens - liberated by monocytes, neutrophils and macrophages during phagocytosis -- interleukin-1 (IL-1) and tumor necrosis factor (TNF) -- you have a fever to help fight the infection; denature the infection's proteins; needs to be a controlled fever -- pyrogens are fever causing increase in body temperature -- hypothalamus (POA = pre-optic area) -- 102 degree is when it starts to become dangerous (can induce a comma and fry your brain)

White Blood Cells (leukocytes)(phagocytes)

-- innate capacity to recognize and differentiate any foreign material

Surveillance by Leukocytes

-- innate immune response...not specific to a certain microbe -- wbcs are mobile, migratory cells that wander through blood and tissues -- constantly evaluate everything they come across: self or nonself -- immediate action of phagocytosis and inflammation (interaction via pattern recognition receptors like the toll-like receptor family located on wbc membrane) (recognize PAMPs as "red flags" and alerts body to control and eliminate the pathogen)

NonPolar Hormones

-- insoluble in water (hydrophobic, lipophilic) -- can enter target cells directly (why? because they can pass through lipid bilayer) -- include steroids, thyroid hormone, and melatonin (steroids only secreted by gonads and adrenal cortex - corticosteroids: cortisol and aldosterone) (thyroid hormones: T3 and T4 - these are NOT steroids but are lipid soluble) -- can be taken orally in pill form

Action of Insulin

-- insulin binds to receptors on target cells...which are? 1) vesicles with CLUT4 carrier proteins bind to plasma membrane of target cells 2) glucose diffuses through GLUT4 channels by facilitated diffusion 3) occurs in adipose tissue, skeletal muscle, and the liver 4) method by which glucose is "cleared" 5) indirectly stimulates the enzyme glycogen synthase in liver and skeletal muscles to promote sugar storage (glycogenesis) 6) stimulates adipose tissue to store fat (lipogenesis)

Integrins: Physiological Significance Example

-- integrins on monocytes bind to vascular adhesion molecules on the endothelium in an effort to promote adhesion and migration into tissues (diapedesis) -- starts out as a monocyte and invades the tissue and changes into macrophage -- diapedesis = the passage of blood cells through the intact walls of the capillaries, typically accompanying inflammation -- goes from the blood stream and enters the tissue.

Overview of the Major Host Defenses

-- interferons = viruses -- phagocytosis = wbcs -- compliment = compliment inflammatory response -- B and T cells = memory, wbc

Iodine Deficiency (Goiter) (Disease of the Thyroid)

-- iodine deficiency: leads to overstimulation of the thyroid gland (no negative feedback on pituitary gland) and growth of a goiter; also leads to hypothyroidism 1) TSH from anterior pituitary remains elevated which stimulates excessive growth of the thyroid 2) symptoms: high BMR, weight loss, nervousness, increased BP, heat intolerance, irritability 3) treatment: dietary iodine

Molarity

-- is not useful for a discussion of osmosis, since the solute concentration is different depending on the solute -- example: more water is used to make the 1M solution of NaCl (because you are adding almost 3-fold less solute) -- dumping in 1 mole into a flask and bringing it up to 1L total volume (so total volume will always be 1L)

Mast (cells of immune system)

-- leaves bone marrow in immature form, circulates in bloodstream and only matures once in a tissue site; common role in allergy; first line defender against local invasion of pathogens; recruit other inflammatory cells

G-Protein-Coupled Receptor (GPCR)

-- ligand = extracellular binding domain -- extracellular = n-terminus -- heterotrimeric g-protein = c-terminus...

Steroids

-- lipids derived from cholesterol -- example: testosterone (testes) -- example: estradiol (ovaries, testes) -- example: progesterone (ovaries, testes) (especially important during pregnancy to halt our cycle) -- example: cortisol (adrenal cortex) (stress hormone) (secreted by adrenal cortex and gonads - ovaries and testes)

Cell Surface vs. Nuclear Receptors

-- lipophilic hormone (lipid loving) receptors are in the cytoplasm or nucleus -- water-soluble (water loving) hormone receptors are on the outer surface of the plasma membrane -- sometimes considered transcription factors

Hormones that bind to Nuclear Receptor Proteins

-- lipophilic steroid hormones and thyroid hormone (lipid loving; water hating) -- travel to target cells attached to carrier proteins -- at the target cell, dissociate from the carrier protein and diffuse across the plasma membrane (why? because they are lipid-soluble) -- receptors are found within the nucleus and are called nuclear hormone receptors because they activate genetic transcription (for this reason they are also called transcription factors) -- albumin is the most abundant carrier protein in the blood

Thyroid Gland (structure and function)

-- located just below the larynx (has two lobes on either side of the trachea -- secretes: 1) thyroxine (T4); 2) triiodothyronine (T3); 3) calcitonin -- function: 1) growth and development; 2) basal metabolic rate (BMR); 3) blood calcium concentration

Cell Signaling: Principle Concept - Reception

-- lock and key -- physiological significance: it offers specificity (to control physiological responses

Anaphylaxis

-- loss of consciousness -- hives -- swelling of tongue, inability to swallow -- rapid swelling of throat tissues

Natural Lipolysis Mechanism

-- over 30 minutes exercise by jogging, swimming or other exercise eliminates the "free fat acids" in the blood -- by instructions from the central cerebrum, adrenaline from adrenal glands is secreted and noradrenaline from the sympathetic nerve is secreted. The fat of the entire body is resolved to the free fat acids. -- through continuous exercise, the fat of other unexpected portions of the body is also consumed.

Tissue Response: Concentration-Dependent, Concentration

-- low hormone / chemical concentration receptor -- tissues only respond normally when hormone concentrations are at a certain "normal" or physiological level -- at higher pharmacological concentrations (when taken as drugs), effects may be different from normal...why are these higher? (high concentrations may result in binding to receptors of closely related hormones) (this can result in widespread abnormal or adverse side effects) -- example: chronic prednisone use can cause hyperglycemia (oppose insulin actions and stimulate gluconeogenesis in liver)

Hypothyroidism

-- low metabolic rate -- weight gain -- lethargy (due to low metabolic rates) (increased sleep) -- poor adaptation to cold stress and edema -- impaired growth -- coarse, dry skin -- no perspiration -- slow pulse -- constipation -- decreased appetite -- slow reflexes -- depression and apathy -- decreased T4 levels

Water Intake

-- lowers plasma osmolality and osmotic pressure -- kidneys play a critical role

Nonspecific Chemical Defenses - Secretions

-- lysozyme, an enzyme that hydrolyzes the cell wall of bacteria, in tears -- high lactic acid and electrolyte concentration in sweat -- defensins damage cell membranes and lyse bacteria and fungi (skin cells secrete dermicidin which eliminates bacteria on the skin) -- saliva carries microbes into acidic gut -- runny nose is actually flushing out your nasal cavity

Autonomic Nervous System (ANS): Neurotransmitters

-- main components: sympathetic (SNS) (fight or flight); and parasympathetic (PNS) (rest and digest) -- effector organ = spleen, liver, heart, skeletal muscle, etc. -- presympathetic = brain -- IML = intermedial lateral cell column

Gonads - Testes (male)

-- major hormones: androgens (especially testosterone) -- primary target organs: prostate, seminal vesicles, testes, and other organs -- primary effects: stimulates secondary sexual development, spermatogenesis, other effects

Adrenal Medulla Glands

-- major hormones: epinephrine (E); norepinephrine (NE) -- primary target organs: heart, bronchioles, and blood vessels -- primary effects: causes adrenergic stimulation

Gonads - Ovaries (female)

-- major hormones: estrodiol-17beta and progesterone -- primary target organs: female reproductive tract and mammary glands -- primary effects: maintains structure of reproductive tract and promotes secondary sex characteristics

Adrenal Cortex Glands

-- major hormones: glucocorticoids (mainly cortisol - fight or flight); corticosterone; mineralocorticoids (mainly aldosterone); androgens -- primary target organs: liver + muscles (cortisol); kidneys (aldosterone) -- primary effects: glucocorticoids influence glucose metabolism; mineralocorticoids promote Na+ retention, K+ excretion

Pancreatic Islets (Langerhans)

-- major hormones: insulin; glucagon -- primary target organs: liver, skeletal muscle, and adipose tissue primarily -- primary effects: insulin promotes cellular uptake of glucose and formation of glycogen and fat; glucagon stimulates hydrolysis of glycogen and fat

Posterior Pituitary Gland

-- major hormones: release of oxytocin; release of anti-diuretic hormone -- primary target organs: ADH - kidneys and blood vessels; Oxytocin - uterus and mammary glands -- primary effects: ADH - promotes water retention and vasoconstriction; Oxytocin - stimulates contraction of uterus and mammary secretory units, promoting milk ejection

Hypothalamus

-- major hormones: releasing and inhibiting hormones (production of ADH - anti-diuretic hormone; production of oxytocin; production of regulatory hormones) -- primary target organs: anterior pituitary -- primary effects: regulates secretion of anterior pituitary hormones

Thyroid Gland

-- major hormones: thyroxine (T4); triiodothyronine (T3); calcitonin (CT) -- primary target organs: most organs -- primary effects: thyroxine and triiodothyronine promote growth and development and stimulate basal rate of cell respiration (basal metabolic rate or BMR); calcitonin may participate in the regulation of blood Ca2+ levels

Anterior Pituitary Gland

-- major hormones: trophic hormones (follicle stimulating hormone; growth hormone) -- primary target organs: endocrine glands and other organs -- stimulates growth and development of target organs; stimulates secretion of other hormones

Brown Adipose Tissue (brown fat)

-- major site of thermogenesis (heat production) -- primarily found in newborns because they cannot regulate their temperature -- in adults it contributes calories and heat production -- sympathetic nervous system activation releases norepinephrine which uncouples electron transport chain thereby promoting increased beta-oxidation of fatty acids to generate more body heat

B-Cells

-- make antibodies against antigens; adaptive immune response

Anterior Pituitary Gland

-- makes its own hormones and releases them -- hypothalamus --> axon (via vesicles) --> blood (micro-circulation) --> bathes endocrine cells --> bloodstream -- more indirect -- example: GnRH released from hypothalamus (at primary capillaries) promotes release of FSH and LH from _____ (at secondary capillaries into bloodstream); enters bloodstream; travels to target cells in ovary or testes to promote follicular maturation (GnRH is from the hypothalamus --> FSH) -- promoting and inhibiting

Cell Signaling: Nuclear Receptors

-- many lipid-soluble regulatory molecules act as transcription factors 1) lipid-soluble hormone diffuses into cell 2) activated receptor hormone complex alters gene expression 3) newly formed mRNA directs synthesis of specific proteins on ribosomes 4) new proteins alter cell's activity

Immune System Cells

-- mast -- dendtritic -- macrophage -- natural killer cell -- compliment protein -- granulocytes (basophil, eosinophil, neutrophil) -- T cells -- B cells

Chemotaxis

-- migration in response to specific chemicals at the site of injury or infection -- chemokines -- chemokines drive chemotaxis (attraction to chemokines; "come over here, not here")

Purpose of Cell Signaling Components

-- overall ______ is to take the ECF signal with an end result of creating a physiological response

How Thyroid Hormones Work

-- molecular mechanisms of thyroid hormones are similar to those of steroid hormones (lipophilic) -- T3 and T4 travel in circulation bound to a carrier protein called thyroxine-binding globulin (carrier proteins have a higher affinity for T4 though so the amount of unbound or "free" T3 is 10x higher than T4 in the blood) -- "free" thyroid hormones pass through lipid bilayer of target cells (T4 is enzymatically converted to T3 - T3 just stays itself - once inside the target cell) (bind to nuclear receptors to promote transcription of target genes)

Pathogen-Associated Patterns (PAMPs)

-- molecules shared by microorganisms -- structures on all types of microorganisms -- invaders -- skull and crossbones flags -- flagellin, LTA (gram+), LPS (gram-)(indotoxin - cockroach dust, highly inflammatory), peptidoglycan, dsRNA (viruses)

Chemokines (mediators of the inflammatory response)

-- monocytes circulating throughout bloodstream; chemokines and integrins tell the monocytes where to settle down (landing zone for monocytes to roll onto and latch); once through endothelial cells it is a macrophage -- integrins = help guide where you need to go (the grabber) -- chemokines = guiding lights (like a landing strip)(fight infection)

Physical or Anatomical Barriers: First Line of Defense - Mucous Membranes

-- mucous coat impedes attachment and entry of bacteria -- nasal hair traps larger particles: involved in sneezing to expel irritants -- cilia = broom (sweeps things)

Autoimmune Diseases

-- multiple sclerosis -- diabetes

Cell Signaling: Synaptic Signaling Type

-- neurons release neurotransmitters into synaptic cleft to target cells (other neurons or target cells in organs) (axons innervate target cell or organ) -- ex. kidney releases neurotransmitter and kidney cell with receptor will bind neurotransmitter

Phagocytes and Phagocytosis

-- neutrophils -- macrophages -- eosinophils -- microbe or other particle = no MHC = nonself -- has LPS (endotoxin) = not good

Innate Defense

-- no immunologic memory -- present at birth -- provide nonspecific resistance to infection -- examples: 1st: physical barriers - skin, tears, coughing, sneezing; chemical barriers - low pH, lysozyme, digestive enzymes; genetic barriers - resistance inherent in genetic makeup of host (pathogen cannot invade) 2nd: (mostly nonspecific) phagocytosis, inflammation, fever, interferon

Passive Transport

-- noncarrier-mediated (high to low) -- net movement down concentation gradient so no energy required -- simple diffusion of lipid-soluble (nonpolar) molecules -- simple diffusion of ions through ion channels -- simple diffusion of water through aquaportin channels ---> osmosis

Self

-- normal cells of the body -- ourself -- autoimmune diseases arise when body mistakes self for foreign

Hormone Interactions: Antagonistic Effects

-- occurs when hormones work in opposite directions -- example: insulin and glucagon are both produced i the pancreas and affect adipose tissue but...insulin stimulates fat storage (because if the energy is not being used it stores it as fat) and glucagon stimulates fat breakdown (because glucose is gone so it breaks down the fat for energy) -- example: estrogen and prolactin's effect on lactation...prolactin promotes lactation and high estrogen concentrations during pregnancy inhibits the secretion of prolactin

Hormone Interactions: Permissive Effects

-- occurs when one hormone makes the target cell more responsive to a second hormone -- example: previous exposure to estrogen makes the uterus more responsive to progesterone (via an upregulation of progesterone receptors) -- example: increased secretion of parathyroid hormone (PTH) enhances the ability of vitamin D3 to stimulate calcium absorption in the intestine

Hormone Interactions: Synergistic Effects

-- occurs when two or more hormones work together to produce a particular effect -- effects may be ADDITIVE: when epinephrine and norepinephrine each affect the heart in the same way, but together they produce an even greater response (synergy) (NE increases hr via beta-receptors in the pacemaker of the heart - SA node - and bp via alpha-AR in the vasculature - vasoconstriction - as well as due to increased force of ventricular contraction through beta-ARs) (epi increases peripheral resistance - vasoconstruction - via alpha-AR and increase cardiac output via beta-AR receptors in heart) (CO = HR x SV) -- effects may be COMPLIMENTARY: when each hormone contributes to a different piece of an overall outcome (i.e. producing milk requires estrogen, prolactin, and oxytocin)

Inflammatory Response

-- occurs within minutes and can last for hours or chronically Symptoms: -- redness: increased circulation and vasodilation in injured tissues in response to chemical mediators (nutrients, oxygen, wbcs are all necessary for repair) -- warmth: heat given off by the increased blood flow -- swelling: increased fluid escaping into the tissue as blood vessels dilate - edema occuring; wbcs, microbes, debris, and fluid collect to form pus; prevents spread of infection -- pain: stimulation of nerve endings

Adrenal Gland Structure

-- on top of the kidneys -- outer adrenal cortex (glandular epithelium that secretes steroid hormones in response to ACTH (adrenocorticotropic hormone) -- inner adrenal medulla (neural tissue that secretes epinephrine and norepinephrine in response to sympathetic neural stimulation) -- function as separate glands

Cell Signaling: Signal Amplification

-- one messenger molecule leads to phosphorylation of millions of proteins 1) one messenger binds to one receptor 2) several G proteins are activated 3) each G protein activates an adenylate cyclase 4) each adenylate cyclase generates hundreds of cAMP molecules 5) each cAMP activates a protein kinase A 6) each protein kinase A phosphorylates hundreds of proteins

Hypertonic

-- osmotically active solutes at a higher concentration than the other solution (water out of rbc causing it to shrink)

Hypotonic

-- osmotically active solutes at a lower concentration than the other solution (water into rbc causing it to expand and possibly burst) -- pure water is hypotonic because it has essentially no solutes at all while cells do - they require ions, proteins, all kinds of things to function

Diabetes (Autoimmune Disease)

-- pancreatic beta-cells secrete autoantigens which alerts the immune system that there is an invader (even though there is not) so then the pancreatic beta-cells are targeted for attack

Polypeptides + Proteins

-- peptide: shorter than 100 amino acids -- protein: longer than 100 amino acids -- example: anti-diuretic hormone (ADH) (peptide-9aa) (water retention and vasoconstriction) and oxytocin (posterior pituitary) (peptide-9aa) (uterine and mammary contraction) -- example: insulin (pancreas-beta cells) (peptide-21 + 30aa double chain) (cellular glucose uptake, lipogenesis, and glycogenesis) -- example: growth hormone

Engulfment (mechanisms of phagocytosis)

-- phagosome: where "prey" is jailed until killing -- phagolysosome: lysosome containing bactericides fused with phagosome (death in about 30 minutes)

Tissue Response: Concentration-Dependent

-- plasma hormone concentrations indicate the rate secretion by respective endocrine glands (hormones do not generally accumulate in blood because they are rapidly cleared by target organs or the liver)

Plasma Membrane Transport: Bidirectional

-- plasma membrane is semi-permeable -- it allows some molecules to cross but not others -- can move through: oxygen, carbon dioxide, and other small, nonpolar molecules; some water molecules (fatty acids; vitamins - A, D, E, K; steroids) -- can NOT move through: glucose and other large, polar, water-soluble molecules; ions (e.g. H+, Na+, K+, Ca++, Cl-); water molecules (polysacharides, amino acids, glucose, nucleic acids)

Oxytocin

-- posterior pituitary -- contractions / lactation -- uterine muscles / mammary glands

ADH (antidiuretic hormone)

-- posterior pituitary -- water retention = vasopressin --> acts on kidney tubules to retain water -- kidney tubules

Prohormones + Prehormones: Skin

-- prehormone: Vitamin D3 -- active products: 1, 25-dihydroxyvitamin D3 -- conversion (through hydroxylation reactions) occurs in the liver and the kidneys

Prohormones + Prehormones: Testes

-- prehormone: testosterone -- active products: dihydrotestosterone (DHT); DHT and other 5alpha-reduced androgens are formed in most androgen-dependent tissue -- active products: estradiol-17beta (E2); E2 is formed in the brain from testosterone, where it is believed to affect both endocrine function and behavior; small amounts of E2 are also produced in the testes

Prohormones + Prehormones: Thyroid

-- prehormone: thyroxine (T4) -- active products: triiodotyronine (T3) -- conversion of T4 to T3 occurs in almost all tissues

Insulin

-- primary hormone regulating plasma glucose concentration -- secreted by beta-cells when blood glucose levels rise after a sugary or carbohydrate meal -- purpose is to lower blood glucose levels to the "normal" range

Mineralocorticoids (Adrenal Cortex)

-- primary targets: kidneys -- hormone effects: increase renal reabsorption of Na+ and water (especially in the presence of ADH and accelerate urinary loss of K+) -- function: acts on the distal convoluted tubules of the renal nephrons; regulates uptake of sodium and acid/base balance -- secretion control is made by: low blood glucose levels -- regulatory control: stimulated by antiotebnsin II, elevated plasma K+, or a fall in plasma Na+; inhibited by ANP and BNP

Epinephrine, Norephinephrine (Adrenal Medulla)

-- primary targets: most cells -- hormone effects: increase cardiac activity, blood pressure, glycogen breakdown, blood glucose levels; releases lipids by adipose tissue -- function: fear, fight, fright syndrome -- secretion control is made by: sympathetic nervous system -- regulatory control: stimulated during sympathetic activation by sympathetic preganglionic fibers -- medulla = neural tissue (fight or flight)

Adrogens (Adrenal Cortex)

-- primary targets: most cells -- hormone effects: not important in adult men; encourages bone growth, muscle growth, and blood formation in children and women -- regulatory control: stimulated by ACTH -- weak sex hormones; supplement gonads (DHEA)

Glucocorticoids (cortisol - hydrocortisone, corticosterone) (Adrenal Cortex)

-- primary targets: most cells -- hormone effects: release amino acids from skeletal muscles and lipids from adipose tissue; promote peripheral utilization of lipids; anti-inflammatory effects -- function: raises glucose levels in the blood, stimulates glucose production by cells, reduce the inflamatory response -- secretion control is made by: raised blood glucose levels -- regulatory control: stimulated by ACTH from anterior lobe of pituitary gland -- hydrocortisone is an anti-inflammatory -- endogenous vs. exogenous sources impart different physiological effects

Cytokines (Mediators of the Inflammatory Response)

-- pro-inflammatory response = other symptoms occur; down regulation; end up with MODS/MOF (common in clinics, doesn't take much) -- perfect scenario is acute and quick -- anti-inflammatory response = can't fight the infection; easing things down; cleaning out -- produced through receptor like genetic defense drawing (mine); can be used as biomarkers (IL-6 is a biomarker for MI) -- macrophages is the #1 source of cytokines

Second Line of Defense

-- protective cells and fluids -- tight junctions -- inflammation and phagocytosis (1st responders) -- nonspecific -- innate immune system

Toll-Like Receptors (recognition of foreign cells)

-- protein receptors within cell membrane of macrophages -- detect foreign molecules and signal the macrophage to produce chemicals (cytokines) to stimulate an immune response -- phagocytic cells migrate to site of infection by following the "scent" of chemokines (chemotaxis)

Glycoproteins

-- proteins bound to one or more sugars -- example: follicle-stimulating hormone (FSH) and Luteinizing hormone (LH) (anterior pituitary)

Compliment Protein

-- proteins that helps antibodies and macrophages clear pathogens (opsonization, chemotaxis, cell lysis)

G-Proteins: Receptor / G-Protein / Effector

-- receptor = cell surface or membrane; pm; c-terminus -- g-protein (GPCR) -- effector (IC)

G-Proteins: Three Protein Subunits

-- receptor proteins that bind to a signal and enzyme proteins that produce a second messenger are rarely localized together within the plasma membrane (they require something to shuttle between them) (____ are made up of 3 subunits - alpha, beta, and gamma; dictate the activity of cAMP) (one subunit dissociates when a signal molecule binds to the receptor and travels to the enzyme or ion channel) -- image is and activated enzyme (adenylate cyclase - makes cAMP - intracellular)

Tissue Response: Priming Effects / Up-Regulation

-- responsiveness of target cells can be affected by variations in the concentration of hormone within its physiological range (due to the direct effects of hormone concentration of receptor expression) (upregulation: some target cells respond to a particular hormone by increasing the number of receptors it has for that hormone; making it more sensitive to subsequent hormone release and have a greater response)

Isosmotic

-- same osmolality (1 osm unit : 1 osm unit) -- a solution may be isosmotic but not isotonic (depends on the permeability of the membrane)

Nonspecific Chemical Defenses - Skin

-- sebaceous secretions are antimicrobial -- acidic (slightly) pH (inhibitory to many microbes)

Cell Signaling: Principle Concept - Transduction

-- second messengers and intracellular messengers / mediators -- they drive the response -- must have a cellular response to drive the physiological response

Functions of the Adrenal Cortex

-- secretes hormones made from cholesterol (called corticosteroids or corticoids) -- three categories (all derived from cholesterol): 1) mineralocorticoids - regulate Na+ and K+ balance (water volume) (example: aldosterone - retains sodium and water while excreting potassium in the urine) (effects on blood volume and pressure? yes); 2) glucocorticoids - regulate glucose metabolism (promote glycogenolysis and anti-inflammatory) (example: cortisol - hydrocortisone; stimulated by ACTH by anterior pituitary; endogenous vs. exogenous sources impart different physiological effects; 3) adrenal androgens are weak sex hormones that supplement those made in the gonads (example: DHEA)

Adrenal Glands

-- secretes hundreds of compounds including cortisone and adrenaline which helps you react to emergencies -- regulates your metabolic processes in the cells, water balance, blood pressure, etc.

Parathyroid

-- secretes the hormones necessary for calcium absorption

Interferons

-- small protein produced by certain wbcs and tissue cells -- produced in response to viruses, RNA, immune products, and various antigens -- bind to cell surfaces and induce expression of antiviral proteins and inhibit expression of cancer genes -- viruses = _____ -- viruses infect you by hijacking your transcriptional and translational machinery, _____ kill it at the mRNA level

Inflammation

-- sole purpose is to restore homeostasis by... 1) mobilizing and attracting immune components to the site of injury 2) set in motion mechanisms to repair tissue damage and clear away harmful substances 3) destroy and block microbes from further invasion

Osmolality (Osm)

-- solutes that DO dissociate -- electrolytes that dissociate in water have to be assessed differently -- NaCl dissociates into Na+ and Cl- in water and must be counted as separate paticles (NaCl ---> Na+(aq) + Cl-(aq) (aq = aqueous) -- a 1molal NaCl solution would acutally be a 12 Osm solution (because 1 Osm unit for sodium + 1 Osm unit for chloride) -- if inside the semipermeable sack contains 1 molal glucose (which is 1 Osm unit) and the membrane is not permeable to glucose, water will move outside. Because NaCl will dissociate, generating 2 Osm units total. Thus the EC solution is hypertonic. -- upon completion of osmosis, the osmolality of the solution inside the sack and outside in the beaker is equal. -- a) High mosmolality high sol. (2); low water; high OP; high OSM (make sure to see what the membrane is permeable to, and then which direction is water moving)

Osmolality (Osm)

-- solutes that do not dissociate -- total molality of a solution when you combine all of the molecules within it -- a 360g (2 molality) glucose solution compared to a solution containing 180g glucose (1 molality) + 180g fructose (1 molality) would have the same osmolality...why? -- these are both 2 Osm solutions: glucose solution = 2 Osm; glucose + fructose solution = 1 + 1 = 2 Osm -- Each molal is equivalent to 1 Osm unit. Such that 2 molals of glucose equates to a 2 Osm solution inside the membrane sack -- the "extracellular" environment contains a solution of 1 molal glucose (1 Osm unit) and 1 molal of fructose (1 Osm unit) such that 1 Osm unit + 1Osm unit = 2 total Osm units. Thus there is no net movement of water between the membrane sack and extracellular environment because the total number of solute particles is equal.

Genetic Defenses

-- some hosts are genetically immune to the diseases of other hosts (genetically engineered TLR4-deficient mice are hyporesponsive to LPS) (people with sickle-cell are resistant to malaria) -- some pathogens have great specificity (host range) (cats can't get mumps from humans) -- some genetic differences exist in susceptibility (natural mutations in TLR4 confer varying degrees of responsiveness to humans which can directly contribute to increased mortality) -- TLR (part of innate immune response) - are the first immune soldiers (sentinels); nfkb factor (nfkappab) translocates; binds micro-organism and culminates inflammation; signals to rest of body "alert, alert, alert we have an infection somewhere"; dual purpose, but main function is immunological defenses -- some people may have a mutation that can allow them to die instead of fighting the infection -- pro-inflammatory and anti-inflammatory responses

The Thyroid Gland and Calcitonin

-- source: thyroid gland -- function: if blood calcium levels are high: 1) inhibits release of calcium from bone and 2) stimulates excretion of calcium in the kidneys to lower blood calcium levels

Adaptive Immunities

-- specific -- must be acquired -- memory comes into play (immunologic) -- vaccines -- specific -- examples: T lymphocytes, B lymphocytes, antibodies

Posterior Pituitary Gland

-- stores and releases hormones made in the hypothalamus -- the axons of these neurons innervate the _____ -- the nerve terminals release ADH and oxytocin into capillaries of the _____ (stores until needed) (these hormones are now in circulation) -- hypothalamus --> axon (via vescicles) --> innervation of cells in the ____ --> bloodstream -- more direct -- example: ADH is stimulated by an increase in blood osmolality (the more concentrated your blood, the more ADH will be released in an effort to dilute your blood)(increase in blood osmolality means that you are dehydrated) (activates hypothalamic osmoreceptors that detect this high osmolality) (need to have a stimulus) -- example: Oxytocin is stimulated by suckling (because oxytocin is involved in lactation)

Stress and the Adrenal Gland

-- stress increases secretion of ACTH from anterior pituitary (result: increased glucocorticoid release from adrenal cortex) -- the stress hormones are: glucocorticoids, epinephrine, and CRH (corticotropin-releasing hormone); good for proper recovery after stress, such as an illness or trauma; cortisol helps inhibit the immune system so it does not overrespond (which causes MODS/MOF) -- Adrenal resistance is basically where the stress keeps coming so the adrenals try to keep up by producing more and more cortisol until the adrenals have nothing left to give. They become worn out. Tired. They really tried to keep up with you but your organs are meant to endure long-term stressors so they eventually tire out.

Extracellular Factor (ECF)

-- substrate or ligand (can be growth factor, hormones, cytokine)

Phagocytosis

-- survey tissues and discover microbes, particulate matter and injured or dead cells -- ingest and eliminate these materials -- extract immunogenic information (antigens) from foreign matter

Hormone Interactions

-- target cells and organs are usually responsive to several different hormones (why? because regulation of organ function is a highly dynamic and complex process)

Metabolism

-- the conversion of nutrients into energy and building materials to meet your body's needs

Osmotic Pressure: Outside Forces

-- the force surrounding a cell required to stop osmosis...the pressure needed to stop osmosis -- a higher solute (low water) concentration would require a higher osmotic pressure (this means water concentration is low) (so the cell would have to really resist allowing its water to flow outwards - high inside to low outside - thereby preventing shrinkage) -- pure water has an osmotic pressure of zero

Hypothalamic-Pituitary Axis (HPA)

-- the relationship between the hypothalamus, anterior pituitary and the target tissue -- highly active in the stress response -- inhibition can occur at the 1) pituitary gland level, inhibiting response to hypothalamic hormones or 2) hypothalamic level, inhibiting secretion of releasing hormones (which would normally act on the anterior pituitary)

Diffusion Rate

-- the steeper the concentration gradient the faster the diffusion rate -- regardless of what side has highest/lowest solute concentration -- increasing temperature slightly can increase it...why? because is makes molecules move faster -- size matters -- permeability of membrane -- surface area of membrane (larger, increased rate)

Immunopathology

-- the study of disease states associated with underactivity and overactivity of the immune response 1) allergy, hypersensitivity 2) autoimmunity 3) immunodeficiency 4) cancer

Endocrinology

-- the study of endocrine glands (ductless) and the actions of the hormones they directly release into the circulation -- effects of hormones are modulated by receptors expressed in cells of target organs (gamma)

Tissue Response: Concentration-Dependent, Hormone Half-Life

-- the time required for the plasma concentration of a given amount of hormone to be reduced by half (ranges from minutes to hours to days) (most hormones are removed from the blood by the liver and converted to less active products)

Herd Immunity

-- threat to community if not adopted -- some of the population gets immunized -- contagious disease spreads through some of the population

Actions of Thyroid Hormone

-- thyroid hormones exert their actions through the activation of genes in order to: 1) stimulate protein synthesis 2) promote maturation of the nervous system 3) increase rates of cellular respiration 4) elevate basal metabolic rate (BMR) (resting rate of calorie - E - expenditure by body)

Nucleus

-- transduction occurs to drive a physiological response -- genes must be transcribed specifically to that physiological response that needs to be generated

Extracellular Environment: function of the blood

-- transports: 1) oxygen from lungs to periphery...why? To feed the body; 2) carbon dioxide (waste) from body to lungs for removal (by what mechanism?)...why? exhaling; 3) nutrients derived from food in the intestine to body cells; 4) nutrients between organs (glucose from liver to brain; lactic acid from muscles to the liver...why? It goes there to be converted to pyruvate then to G-6-P which can enter glycogenesis or gluconeogenesis); 5) metabolic wastes from body cells to the liver and kidneys for elimination...why the liver and kidneys? filtration of blood; 6) regulatory hormones released from endocrine organs to cells within their target organs

Pituitary Gland

-- trophic hormones are those that are released by the posterior pituitary and act on other endocrine organs -- connected to hypothalamus by the infundibulum (stalk) -- divided into anterior (adenohypophysis) lobe and poster (neurohypophysis) lobe -- it is the "hormone control center" -- it is protected by bone

Monocytes

-- turn into macrophages (circulate as ____, but once migrate they are targeted to site of infection and burrow down they are now microphages)

Beta-Oxidation

-- turning free fatty acids into energy -- enzymes convert fatty acids to form acetyl CoA (so for every 2 carbons on the fatty acid chain, 1 acetyl CoA can be formed) (example: a 16-carbon fatty acid --> 8 acetyl CoA) (each acetyl CoA enters the Krebs cycle now) (so then each acetyl CoA generates 10 ATP) ( so that 16-carbon fatty acid generated 80 ATP - 8 acetyl CoA x 10 ATP) + 28 in electron transport = 108 ATP) During electron transport 4 ATP are generated from NADH an FADH and because a 16-carcon fatty acid would take 7 spins around the Krebs cycle (each time removes 2-carbons from the fatty acid, until you are left with a 2-carbon final product), 4 x 7 = 28 ATP generated just from the electron transport chain.

Body Fluids

-- two (2) compartments (intracellular and extracellular) -- intracellular (cytoplasm): 67% of our water is within cells -- extracellular: 33% (20% blood plasma; 80% tissue fluid or interstitial fluid) (found in the gel-like extracellular matrix) (connects the intracellular compartment with the blood plasma) (formed continuously recycles from and to blood plasma)

***G-Proteins: Types of G-Alpha Subunits

-- type dictates signaling cascade -- GPCRs can mainly be sub-classified by g-protein type, i.e. g-alpha(s), g-alpha(i), g-alpha(q) -- the amount of decrease in cAMP levels by gi-coupled receptor activation depends on the basal level of cAMP present within the cells; often, the effects of this inhibition are more easily observed when a specific agent, such as forskolin, is used to activate adenylate cyclase 1) subunit activation: g-alpha(i) or (Gi); effector + signal transduction: --> inhibition of Adenylate Cyclase (AC) --> decrease in intracellular cAMP concentration; second messengers: cAMP 2) subunit activation: g-alpha(s) or (Gs); effector + signal transduction: --> stimulation of Adenylate Cyclase (AC), --> increase in intracellular cAMP concentration 3) subunit activation: g-alpha(q) or (Gq); effector + signal transduction: --> Phospholipase C (PLC) induction and triggers the inositol phosphate cascade --> transient increase in intracellular IP3 concentration and subsequent calcium release from the endoplasmic reticulum (ER)

Nonspecific Chemical Defenses - Excretions

-- vomiting and defecation release noxious substances and microbes from body (vomit = cleaning out system) (poop = lots of bacteria) -- urination flushes urethra

Osmosis

-- water molecules do not carry a charge, so they can pass through the plasma membrane slowly (aided by aquaporins) -- must be a solute concentration difference on either side of a membrane permeable to water -- the membrane must be impermeable to the solute...why? so that you can... -- or the concentration difference will not be maintained (solutes that cannot cross and permit osmosis are called osmotically active) -- water moves down its concentration gradient (from low solute concentration to high solute concentration)

Polar Hormones

-- water soluble (hydrophilic, lipophobic) -- cannot pass through plasma membranes (why? because lipids can't go through) -- includes polypeptides, glycoproteins, catecholamines (norepinephrine, epinephrine and dopamine) -- must be injected if used as a drug (why? polypeptide and glycoproteins would be digested prior to absorption if taken orally) -- example: must inject insulin; metformin is oral because it acts through a different mechanism - inhibits gluconeogenesis in liver thereby reducing hyperglycemia

***Second Messengers: The cAMP + Ca++ Pathways

-- when a signal molecule such as epinephrine binds to a cell surface receptor protein, it activates a g-protein on the inside of the cell -- the g-protein then stimulates adenylyl cyclase to produce large amounts of cyclic AMP within the cell -- the cyclic AMP then binds to and activates a target protein such as alpha-kinase, which adds phosphates to specific proteins in the cell -- the effect of this phosphorylation depends on the identity of the cell and the proteins that are phosphorylated -- calcium ions also serve as second messengers. In response to a signal molecule from other cells, the cell surface receptor protein activates a g-protein, which in turn activates the enzyme phospholipase C -- this enzyme catalyzes the production of inositol triphosphate, which diffuses through the cytoplasm to the endoplasmic reticulum -- the inositol triphosphate binds to and opens the calcium channels, allowing calcium ions to flow from the endoplasmic reticulum into the cytoplasm -- the calcium ions trigger proteins sensitive to calcium to initiate a variety of activities OR a) Channel-Linked Receptors: 1) signal binds; 2) channel opens; 3) ions flow across membrane b) Enzyme-Linked Receptors: 1) signal binds; 2) enzyme activated; 3) enzyme generates product c) G-Protein-Coupled Receptors: 1) signal binds; 2) g-protein binds; 3) g-protein activated d) Intracellular Receptors: 1) signal binds; 2) activated receptor regulates transcription

Diffusion of a Solute

1) a lump of sugar is dropped into a beaker of water 2) sugar molecules begin to break off from the lump 3) more and more sugar molecules move away and randomly bounce around 4) eventually, all of the sugar molecules become evenly distributed throughout the water

Function of Integrins

1) adhesion molecule - connecting cells and the extracellular matrix 2) relay signals - between intracellular and extracellular environment 3) confer polarity to cells - such that one side is functionally different from the other (apical vs. basal) 4) contribute to cell adhesion in tissues 5) contribute to cell motility 6) impact cell proliferation (growth, increasing number) 7) bind to secreted regulatory chemicals (signal transduction) (primarily mediate growth factor binding to their receptors)

Factors that can impact blood osmolality

1) dehydration 2) salt intake 3) water intake

Endocrine Glands Characteristics + Functions

1) ductless 2) secrete hormones directly into the blood (hormones are biologically active) 3) hormones are carried to target cells expressing receptors specific for those hormones (physiological significance: recognition of hormone drives physiological response downstream) 4) neurohormones are secreted by specialized cells of the hypothalamus (some regulatory molecules can be both a neurotransmitter - only released into synaptic cleft; and neurohormone - released into blood) (i.e. norepinephrine - neurotransmitter that is also a hormone - plays a huge role in neuronal and organ function) 5) hormones help regulate body metabolism, growth, and reproduction 6) many organs secrete hormones other than those discussed in this chapter such as the heart, liver, kidneys, and adipose tissue -- examples: insulin = insulin receptor; norepinephrine / epinephrine = adrenergic receptor (alpha, beta, adrenergic); FSH = FSHR

Cell Signaling: Four Types

1) gap junctions 2) paracrine signaling 3) synaptic signaling 4) endocrine signaling

Adrenal Gland - Short-Term Stress Response

1) glycogen --> glucose; increased blood glucose 2) increased blood pressure 3) increased breathing rate 4) increased metabolic rate 5) change in blood flow patterns -- all external...controlled by us...

Common Aspects of Neural + Endocrine Regulation, Similarities between Neurotransmitters and Hormones

1) hormones and neurotransmitters both interact with SPECIFIC receptors (specificity is key...why? because you want to make sure that you are reacting with the right thing - gabba and not other receptors) 2) binding to a receptor causes a change within the cell, which brings about a physiological response downstream 3) there are mechanisms to turn off target cell activity (the signal is either removed or inactivated) (this serves as a point of regulation - without it physiological control would be impossible) 4) some hormones can also be neurotransmitters in the CNS

Steps in the G-Protein Coupled Receptor Pathway:

1) ligand binds to receptor 2) conformational change in receptor 3) G-protein alpha subunit dissociates from beta/gamma complex (g-alpha is now activated) 4) alpha subunit moves through membrane and binds to adenylate cyclase (or an ion channel) 5) alpha subunit hydrolyzes GTP into GDP causing alpha / beta / gamma to regroup and move back to the receptor protein (g-alpha is now deactivated)

G-protein-coupled receptors

1) nerotransmitter (ligand) binds 2) G-protein is activated 3) G-protein subunits or intracellular messengers modulate ion channels 4) ion channel opens 5) ions flow across membrane

Ligand-gated ion channels

1) neurotransmitter (ligand) binds 2) channel opens 3) ions flow across membrane

Mechanism of Steroid Hormone Action

1) non-genomic action 2) genomic action

What are the different ways in which signals can be integrated?

1) one receptor activates multiple pathways 2) different receptors activate the same pathway 3) different receptors activate different pathways; one pathway affects the other

Cell Signaling: Principle Concept

1) reception 2) signal transduction 3) response

****Mechanisms Mediating Receptor Desensitization

1) receptor sequestration by endosome (removes from cell surface - taking it in) 2) receptor downregulation by lysosome (removes from cell surface) 3) receptor inactivation by inactivation of signaling mediators (downstream effectors) (inactivates receptor at C-terminus essentially) 4) reduction in transcription and translation of receptor

What is the general flow of information during cell signaling?

1) receptor-ligand binding 2) signal transduction (via secondary messengers) 3) cellular responses 4) changes in gene expression

Mechanisms of Phagocytosis

1) recognition 2) engulfment 3) destruction and elimination

Signal Transduction Steps:

1) recognition - receptor is recognizing the ligand (signal) 2) signal transduction - 2nd messenger activates the intracellular mediators (also known as the relays); so important because...amplification (amplifying the signal) 3) regulating gene expression - physiological outcome is physiological response (ex. promoting blood clotting, immune response, response to MI) -- heterotrimeric g-protein (alpha-beta-alpha: GDP inactive)(c-terminus...) -- colocalization = coming together of alpha and proteins (mixing of "red" and "blue" = "purple")

G-Protein Overview:

1) resting state: receptor is not bound to ligand; g-alpha subunit is bound to GDP and associated with g-beta-gamma 2) ligand binds receptor; the receptor binds a g-protein; g-alpha releases GDP and acquires GTP 3) g-alpha and g-beta-gamma subunits separate 4) g-protein subunits activate or inhibit target proteins, initiating signal transduction events 5) the g-alpha subunit hydrolyzes its bound GTP to GDP, becoming inactive 6) subunits recombine to form an inactive g-protein

Adrenal Gland - Long-Term Stress Response

1) sodium ions and water by kidneys (conversion of proteins and fats to glucose) 2) increased blood volume and blood pressure (immune system suppressed) -- all external...controlled by us...

Function of Cortisol (hydrocortisone)

1) stimulates protein degradation (stimulates gluconeogenesis and glycogenolysis and inhibits glucose utilitization to raise blood glucose levels) (stimulates lipolysis to raise FFAs in blood) -- end result: provide more energy -- exogenous glucocorticoids are used medically to suppress immune response and inhibit inflammation; can have many negative side effects

Functions of a healthy functioning immune system

1) surveillance of the body: primarily wbcs 2) recognition of foreign material 3) destruction of entities deemed to be foreign

Where most of our energy comes from

1. 80-85% of energy is stored as fat (14,000 kcal) 2. less than 2,000 kcal is stored as glycogen (2/3 of which is stored in skeletal muscle) 3. 15-20% of energy is stored as protein (not extensively used for energy though)(if so...muscle breakdown)

Endocrine

= hormones (travel long distances via the blood stream)

D. Decreased TSH.

A 19-year old female student has had difficulty focusing on school work for the past month. She complains that the classrooms are too hot. She seems nervous about homework assignments, exams and grades. She has lost 10 lbs in the past month. On physical examination, her body temperature is 37.8 C, pulse 100/minute, respiratory rate 19/minute, and blood pressure 140/85 mm Hg. Which of the following laboratory findings is most likely to be present in this woman? A. Decreased catecholamines. B. Increased ACTH. C. Decreased iodine uptake. D. Decreased TSH.

A. mast cell-derived mediators.

A 19-year-old girl has nasal discharge and itching of her eyes in the spring every year. An allergist performed a skin test using a mixture of grass pollens. Within a few minute,s she developed a focal redness and a swelling at the test site. This response is most likely due to A. mast cell-derived mediators. B. the activation of CD4 helper cells and the resultant generation of specific antibodies. C. the activation of neutrophils. D. the activation of cytotoxic T cells to destroy antigens.

D. An adrenal adenoma (a benign tumor of the adrenal gland).

A 35-year-old woman has noted a weight gain of 15 lbs over the past year. On physical examination her blood pressure is higher than normal. Her glucose is 181 mg/dL. Which of the following would you expect to be present in this patient? A. Lung metastatic carcinoma (lung cancer). B. A prolactinoma (pituitary tumor producing more prolactin than normal) C. Grave's disease. D. An adrenal adenoma (a benign tumor of the adrenal gland).

D. Cushing's disease.

A 40-year old obese woman is in a clinic. Her physical and lab tests suggest that she is suffering from hyperglycemia,, muscle weakness, and increased circulating levels of ACTH. The most likely cause of her condition is A. Addison's disease. B. hyperthyroidism. C. hypothyroidism. D. Cushing's disease.

A. Hyperglycemia.

A 50 year-old man has a pituitary tumor that produces excess amounts of growth hormone. Which of the following symptoms would you expect to observe as a result of this condition? A. Hyperglycemia. B. High blood levels of amino acids. C. Immune suppression. D. Decreased urine output.

A. Downregulation of insulin receptors.

A 51-year-old man with a history of type 2 diabetes mellitus comes to the physician for a routine examination. He notes that his blood glucose concentration has been persistently high over the past 4 months and he gained 20 lbs during the holidays. His diabetes has been more difficult to control because weight gain causes which of the following to occur? A. Downregulation of insulin receptors. B. Inhibition of insulin release. C. Increased expression of GLUT-4 transporters. D. Upregulation of insulin receptors.

GTP

A G-protein alpha subunit that has bound ____ is active and can catalyze the activation of other enzymes.

a) can be open at all times.

A channel protein a) can be open at all times. b) can move ions against their electro-chemical gradient. c) moves ions at a rate similar to that of a transporter. d) moves both anions and cations through the same channel.

B. Insufficient iodine in the patient's diet.

A patient appears in a clinic complaining of fatigue and sensitivity to cold. He also has a lump in his neck near his larynx. Blood tests show that he has low levels of T3 and T4. Which of the following is the most likely diagnosis? A. Secondary hypothyroidism. B. Insufficient iodine in the patient's diet. C. Insufficient secretion of TRH. D. Secondary hyperthyroidism.

Use a diagram to show how cyclic AMP is produced within a target cell in response to hormone stimulation and how cAMP functions as a second messenger.

A diagram similar to fig. 11.8 should be drawn. This shows how a hormone binds to the extracellular site of a receptor located in the plasma membrane of the target cell. This activates the receptor to cause the dissociation of G-proteins from the receptor. The G-protein subunits diffuse through the membrane to activate adenylate cyclase, which converts ATP into cyclic AMP (cAMP) and PPi. cAMP then activates protein kinase, which phosphorylates proteins and thereby activates or inactivates specific enzymes.

d) Increased rate of diffusion of sodium into the cells.

A drug is known to cause a change in the resting membrane potential of renal tubular epithelial cells from -60 mV to -50 mV. Which of the following findings could be the cause? a) Decreased rate of diffusion of sodium into the cells. b) Decreased rate of diffusion of potassium into the cells. c) Increased rate of diffusion of potassium into the cells. d) Increased rate of diffusion of sodium into the cells.

Draw a negative feedback loop showing the control of ACTH secretion. Explain how this system would be affected by (a) an injection of ACTH, (b) surgical removal of the pituitary, (c) an injection of corticosteroids, and (d) surgical removal of the adrenal glands.

A figure similar to fig. 11.20 can be drawn to illustrate the negative feedback control of ACTH secretion. (a) An injection of ACTH would increase cortisol secretion from the adrenal cortex, but eventually would reduce endogenous ACTH and cortisol secretion. (b) Removal of the pituitary would eliminate ACTH, thereby causing the adrenal cortex to stop secreting cortisol. (c) An injection of corticosteroids would immediately decrease the anterior pituitary secretion of ACTH. (d) Removal of the adrenal glands would abolish corticosteroid secretion, thereby causing a great increase in ACTH secretion from the anterior pituitary.

B. Intracellular diacylglycerol levels increase.

A hormone activates phospholipase C. Which one of the following changes is most likely to occur following this hormone administration? A. Phosphorylation of protein tyrosine residues will increase. B. Intracellular diacylglycerol levels increase. C. Calcium association with calmodulin will decrease. D. Cytoplasmic calcium concentrations will decrease.

c) Activation of cAMP or Cgmp.

A neurotransmitter binds to a G-protein-linked receptor and activates a specific second messenger in its target cell. Which of the following represents an activity performed by the activated second messenger? a) Inactivation of enzymes that initiate biochemical reactions. b) Direct activation of gene transcription. c) Activation of cAMP or Cgmp. d) Closure of a membrane channel for sodium or potassium ion.

D. All of the above.

A patient is diagnosed with a defective gene that codes for the complement protein C1. Which complement function will be compromised in this patient? A. Recognition. B. Activation. C. Attack. D. All of the above.

A. The primary failure of thyroid gland.

A person with decreased T3 and T4, increased TSH and a goiter most likely be suffering from A. The primary failure of thyroid gland. B. either the hypothalamic or pituitary tumor causing increased production of all the hormones they secrete. C. A hypersecreting thyroid tumor.

B. artificial passive immunity.

A pregnant woman with Rh negative blood type is treated with Rho Gam to prevent the development of antibodies against Rh antigen. This is an example of which type of immunity? A. induced active immunity. B. artificial passive immunity. C. natural active immunity. D. naturally borrowed passive immunity.

Define prohormone and prehormone, and give examples of each of these molecules.

A prohormone is a larger polypeptide precursor of a smaller polypeptide hormone. Proinsulin is an example. A prehormone can be an even larger precursor of a prohormone, such as preproinsulin. However, the term "prehormone" can also be used to indicate a secreted hormone that must be converted by cells of a peripheral organ to become activated. Thyroxine can be considered a prehormone of triiodothyronine, for example; vitamin D, secreted by the skin, is a prehormone that must be converted into 1,25-dihydroxyvitamin D to be active.

d) receptor → G protein → second messenger → biological response

A typical flow of information in a signal transduction pathway would be: a) hormone → second messenger → receptor → biological response b) hormone → second messenger → receptor → biological response c) receptor → second messenger → biological response → G protein d) receptor → G protein → second messenger → biological response

C. TH4.

Activated TH cells differentiate into several subtypes except: A. TH1. B. TH2. C. TH4. D. TH17.

D. both a and b.

Active immunity may be produced by A. contracting a disease. B. receiving a vaccine. C. receiving antibody injections. D. both a and b. E. both b and c.

Describe what would happen to a person's cardiovascular and gastrointestinal physiological systems if they did not have adult stem cells. Hint: first you must define adult stem cells then apply it to the specific circumstance detailed.

Adult stem cells are somatic and remain in our bodies for restoration purposes. They are pluripotent, meaning that they can become anything, like a blank slate. If we did not have these adult stem cells our bodies would not be able to repair themselves. These cells would go to the cardiovascular and gastrointestinal systems and repair the damage done after a heart attack or an ulcer, etc.

Describe how insulin and glucagon secretion are affected by eating and by fasting and explain the actions of these two hormones.

An increase in plasma glucose concentration caused by eating stimulates insulin secretion as it suppresses glucagon secretion. Conversely, a decrease in plasma glucose produced by fasting causes insulin secretion to decline and glucagon secretion to rise. Insulin promotes the uptake of plasma glucose into liver and adipose cells and thereby lowers the blood glucose. Glucagon stimulates the breakdown of liver glycogen and stored fat to increase the blood levels of glucose and fatty acids during fasting. The antagonistic actions of these hormones thereby provide negative feedback compensations during eating and fasting to maintain homeostasis of the plasma glucose concentration.

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Describe the metabolic pathway by which glucose can be converted into fat. How can end-product inhibition by ATP favor this pathway?

E→ A→B→ C→ D

Arrange the following steps in the correct order: A. Dendritic cell reaches the lymph node B. Activation of the T cell C. Extravasation of the activated T cell D. Arrival at the site of infection E. Processing of antigen by the dendritic cell

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Brenda's coach advised her to exercise more gradually. If her muscles obtain a higher proportion of their energy from fatty acids, what benefits would this have?

Interestingly it has been demonstrated that cortisol in these patients undergoes reduced catabolism. What is catabolism and what does reduced catabolism mean for the half-life of cortisol in these patients?

Catabolism releases energy by breaking down large molecules into small molecules. An example of this is muscle atrophy. Since catabolism breaks things down, it would break down the cortisol giving cortisol a increased half-life. This would mean that they would be even harder for patients with PTSD to deal with stress and they may have an increase in inflammation. Dr. CC: chronic str

The higher extracellular solute concentration will mean that it contains low water, thereby drawing OUT water from cwerebellar tissue and reducing swelling.

Cerebral Edema (tonicity; clinical application) -- hypertonic solutions like mannitol are commonly used to treat cerebral edema, a significant cause of mortality in patients suffering from stroke or head trauma Why?

Outside

Cortex

Explain the significance of the isoenzymatic forms of cyclooxygenase in the action of nonsteroidal anti-inflammatory drugs.

Cyclooxygenase (COX), the enzyme needed for the conversion of arachidonic acid to the prostaglandins, is inhibited by nonsteroidal anti-inflammatory drugs (NSAIDSs). The type 1 isoform of COX is produced constitutively by cells of the stomach, kidneys, and blood platelets, whereas the COX-2 isoform is induced by inflammation and promotes the inflammatory condition. The NSAIDS aspirin and indomethacin inhibit both isoenzyme forms to promote their desired anti-inflammatory effects, and to prolong blood clotting by retarding platelet aggregation. However, they can also irritate the stomach. The COX-2 selective NSAIDS, such as Celebrex, can reduce inflammation while not causing as great an irritation of the stomach, but can increase the risk of serious cardiovascular disease.

The membrane potential is the difference in charge across the membrane. Differences in charge, or differences in potential, are measured in units of voltage. Because voltage is a measure of potential difference, two electrodes - one placed inside the cell and one placed in the extracellular environment - are needed. A device that functions as a voltmeter can then measure the potential difference across the membrane between these two electrodes.

Define membrane potential and explain how it is measured.

Isotonic solutions have the same osmolality and osmotic pressure. When one solution is referred to as isotonic, it is because it has the same osmolality and osmotic pressure has plasma. Hypotonic solutions have a lower, and hypertonic solutions have a higher, osmolality and osmotic pressure. Tissue cells exposed to hypotonic solutions will gain water and those exposed to hypertonic solutions will lose water, whereas those exposed to isotonic solutions will do neither. That is why 5% dextrose and normal saline, which are isotonic solutions, are used in hospitals.

Define the terms isotonic, hypotonic, and hypertonic, and explain why hospitals use 5% dextrose and normal saline as intravenous infusions.

Osmosis is the net movement of water by diffusion across the plasma membrane. Osmolality is the total molal concentrations of solutes in a solution, and the osmotic pressure of a solution refers to the pressure needed to stop osmosis into the solution. In order for osmosis to occur, a membrane must separate two solutions that contain different osmolalities and the membrane must be more permeable to water than to at least one of the solutes in these solutions.

Define the terms osmosis, osmolality, and osmotic pressure, and state the conditions that are needed for osmosis to occur.

Active transport is an ATP-requiring process that moves substances across the plasma membrane against their concentration gradients. Primary active transport depends on carrier proteins called "pumps" that are powered by the hydrolysis of ATP. These pumps move substances from lower to higher concentrations, accentuating concentration differences. These differences, maintained by primary active transport, could be used to power secondary active transport in which a different carrier moves a different substance across the membrane. In facilitated diffusion, movement of a substance is always down its concentration gradient and, though a carrier is required, ATP is not needed either directly or indirectly.

Describe active transport, including primary and secondary active transport in your description. Explain how active transport differs from facilitated diffusion.

About 67% of the total body water is in the intracellular compartment. Of the fluid in the extracellular compartment, about 20% is in the blood plasma and 80% is tissue, or interstitial, fluid.

Describe the distribution of fluid in the body.

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Describe the metabolic pathway by which fat can be used as a source of energy and explain why the metabolism of fatty acids can yield more ATP than the metabolism of glucose.

An equilibrium potential is the membrane potential required to stabilize the normal difference in concentration of an ion on the two sides of the plasma membrane if the membrane is permeable to it. The equilibrium potential for K+ is -90 mV, and the equilibrium potential for Na+ is +60 mV. The actual membrane potential is closer to the K+ equilibrium potential because the resting membrane is more permeable to it. If the membrane becomes more permeable to a particular ion, the membrane potential is moved towards that ion's equilibrium potential.

Describe the potassium and sodium equilibrium potentials.

Using diagrams, describe how steroid hormones and thyroxine exert their effects on their target cells.

Diagrams for steroid hormone action should resemble figs. 11.4 and 11.5, and a diagram similar to fig. 11.6 should be drawn for thyroid hormone action. These hormones exert their effects by entering the target cells and binding to receptor proteins. When the receptor is in the cytoplasm, the complex translocates to the nucleus; when the receptor is in the nucleus, the hormone bind to it there. In both cases, this causes the activation of specific genes that produce specific mRNA, thereby causing the production of specific proteins that produce the effects of the hormone in the target cell.

These pumps accentuate the difference in concentration of Na+ and K+ across the membrane by pumping three Na+ out of the cell for every two K+ they pump into the cell. This is needed for at least three functions: (1) the steep Na+ gradient produced by the pumps is needed for secondary active transport (of glucose, for example); (2) these pumps contribute to the potential difference across the plasma membrane, which is required for the electrochemical impulses produced by neurons and muscle cells; and (3) the extrusion of Na+ is required for osmotic reasons, to prevent the undue osmosis of water into cells.

Discuss the physiological significance of the Na+/K+ pumps.

Synaptic regulation occurs by means of neurotransmitter chemicals released from presynaptic axon terminals that diffuse a short distance across a synaptic gap to a postsynaptic cell. Endocrine regulation occurs via hormones secreted by endocrine glands into the blood, which carries the hormones throughout the body to distant target cells. Paracrine regulation occurs by means of regulatory chemicals released by cells of an organ that diffuse to neighboring target cells in the same organ.

Distinguish between synaptic, endocrine, and paracrine regulation.

The student should draw a figure similar to fig. 6.15. This figure illustrates saturation, where the transport rate reaches a plateau at a particular concentration of the diffusing substance - beyond this point, an increase in concentration does not produce an increase in transport rate. The graph also illustrates competition, because two like substances (X and Y in the figure), when present together, decrease the transport rate of each other by competing for carriers.

Draw a figure that illustrates two of the characteristics of carrier-mediated transport and explain how this type of movement differs from simple diffusion.

b) Na+ ions enter the cell along a concentration gradient and along an electrical gradient.

During the resting membrane potential a) K+ ions leave the cell against a concentration gradient but along an electrical gradient. b) Na+ ions enter the cell along a concentration gradient and along an electrical gradient. c) Na+ ions enter the cell along a concentration gradient but against an electrical gradient. d) K+ ions leave the cell along a concentration gradient and along an electrical gradient.

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Explain how energy is obtained from the metabolism of amino acids. Why does a starving person have a high concentration of urea in the blood?

Osmoreceptor neurons in the hypothalamus lose water when the plasma osmolality increases. This stimulates them, promoting a sense of thirst. Also, these neurons stimulate the posterior pituitary gland to secrete antidiuretic hormone (ADH), which stimulates the kidneys to retain water. Thus, in dehydration, we drink more and urinate less, maintaining homeostasis of plasma osmolality.

Explain how the body detects changes in the osmolality of plasma and describe the regulatory mechanisms by which a proper range of plasma osmolality is maintained.

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Explain the function of brown fat. What does its mechanism imply about the effect of ATP concentrations on the rate of cell respiration?

The resting membrane potential is close to the K+ equilibrium potential because the resting membrane is more permeable to K+ than to Na+. It is slightly less negative (about -70 mV compared to -90 mV) because the plasma membrane does allow some Na+ to enter the cell through leakage channels. Because of this, the resting membrane potential does not prevent a new efflux of K+. The slow inward movement of Na+ and outward movement of K+ are countered by the constant activity of Na+/K+ pumps.

Explain the relationship of the resting membrane potential to the two equilibrium potentials.

Simple diffusion refers to membrane transport in which the ions or molecules pass through the plasma membrane down their concentration gradients without requiring specific carrier proteins. Diffusion rate depends on the steepness of the concentration gradient (the difference in concentration between one side and another of the plasma membrane), the surface area of the membrane involved, the permeability of the membrane to the diffusing substance, and on the temperature.

Explain what is meant by simple diffusion and list the factors that influence the diffusion rate.

???

Explain why the liver is the only organ able to secrete glucose into the blood. What are the different molecular sources and metabolic pathways that the liver uses to obtain glucose?

???

For many years, the total number of molecules of ATP produced for each molecule of glucose in aerobic respiration was given as 38. Later, it was estimated to be closer to 36, and now it is believed to be closer to 30. What factors must be considered in estimating the yield of ATP molecules? Why are the recent numbers considered to be approximate values?

Case study: George is feeling unwell. His chief complaint was weakness. His urine test results indicate elevated levels of ketone bodies in the urine. What is this condition called? Upon further evaluation you discover George lacks enzymes necessary for breaking down sugars. How does this new discovery explain 1) his symptom of weakness and 2) the excessive ketones in his urine? Hint: First you must understand what ketones are, how they are generated and from what tissue, and under what conditions they are generated. You must also understand the positive and negative contributions of ketone bodies to survival before applying your knowledge to your assessment and treatment of George.

George has ketoacidosis as a result of uncontrolled diabetes. His body is not able to break down sugars for energy, so they are breaking down his ketones. He is weak and has elevated ketone levels in his urine because his body has become too acidic. He has also lost a lot of water and salts via urination making him dehydrated. He will be treated by admitting him to the hospital and given fluids high in saline to rehydrate as well as insulin to bring his diabetes under control. He will be treated as a diabetic from that point forward.

As a clinician, knowing your patient has low plasma levels of cortisol, what therapy would you offer to help them?

Give them cortisol treatments.

Because they need to be manipulated before they do what they need to do. This is a point of regulation for hormone action.

Hormones involved with metabolism of target cells are often released as less active precursors...?

C. on the cell membrane.

Hormones that use second messenger systems bind to receptors that are located A. in the cytoplasm. B. in the nucleus. C. on the cell membrane. D. within the lysosome.

1) Hypothalamic neural cell bodies produce ADH and oxytocin 2) The axons of these neurons innervate the posterior pituitary 3) The nerve terminals release ADH and oxytocin into capillaries of the posterior pituitary (stores until needed); These hormones are now in circulation

How are hypothalamic hormones released by the posterior pituitary?

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How do all cells receive nourishment? In other words, what is carrying glucose, lipids, amino acids, lactic acid and ketone bodies?

Second Messengers: Membrane Receptors -- polar (water soluble) or large signal molecules bind to receptors on the cell surface -- signal pathway mediator proteins called second messengers integrate the extracellular signal and intracellular-mediated physiological outcome 1) can be ions (typically calcium) (enter the cell through ion channels); 2) can be cytoplasmic proteins

How does a ligand that binds to a cell surface receptor exert its effects inside the cell?

-- osmoreceptor neurons in the hypothalamus stimulate a tract of neurons that terminate in the posterior pituitary ---> causes the posterior pituitary to release antidiuretic hormone / vasopressin (ADH) into the circulation ---> ADH acts on the kidneys to promote water retension such that urination is minimized -- this maintains plasma concentration (osmolality) and blood volume

How does dehydration lead to water retention? (regulation of osmolality)

****1) the adrenal gland secretes cortisol (anti-inflammatory) 2) low cortisol is being produced --> increased inflammation --> MODS/MOF

How would adrenal insufficiency effect patient survival following severe infection?

It has also been reported that there is increased target sensitivity to cortisol. Knowing this, what would you expect the glucocorticoid receptor (receptors for cortisol) expression levels to look like? Would you expect the glucocorticoid receptor to be expressed at high or low levels? Why?

I would expect the glucocorticoid receptor to be expressed at lower levels because for proper recovery after stressful situations you need to have higher glucocorticoid levels being reached. Since cortisol is being broken down too fast, not enough glucocorticoid will be produced to deal with the PTSD response. This may also be a reason why the stress may trigger and maintain these PTSD episodes.

Suppose a person collapsed due to a rapid drop in blood pressure. What would you expect to find regarding the rate and strength of this person's pulse? Why? Is this an example of feedback regulation, and if so, positive or negative? Hint: you must first understand the concept of feedback loops and apply it to his specific scenario.

I would expect to find a low heart rate and decreased pulse because they are not getting enough blood circulation throughout the body. Yes, this is a negative feedback mechanism.

C→ F→D→A→ B→E

Identify the correct order of steps in the synthesis and release of thyroid hormones: A. Endocytosis B. Digestion of thyroglobulin C. Iodide trapping D. Addition of iodine to tyrosine E. Release of hormone F. Iodide is converted to iodine

Receptor proteins for water-soluble regulatory molecules are generally located on the plasma membrane surface, facing the extracellular environment. Interactions between the regulatory molecules and these receptors then generate second messengers that act within the cell to effect the regulation. Lipid-soluble regulatory molecules can cross the plasma membrane and interact with receptor proteins within the cell, either in the cytoplasm or the nucleus.

Identify the location of the receptor proteins for different regulatory molecules.

A- MHC II; B- CD4; E- helper T cell; C MHC I; D- CD8; F- killer T cell

Identify the molecule with letter A ____ which interacts with the structure labeled B ____ on cell labeled E ____. Similarly, the structure labeled C is ____ which interacts with the structure labeled D ___ which is part of the cell F called ________ .

???

If a person is a chronic opioid user for controlling pain, what adaptations would you expect to observe in the smooth ER of this patient?

a) he movement of Na+ out of a cell

If a poison such as cyanide stopped the production of ATP, which of the following transport processes would cease? a) he movement of Na+ out of a cell b) Osmosis c) The movement of K+ out of a cell d) All of these

???

If all cells used glucose as an energy source what would happen to glucose levels? What would we have to do to maintain constant glucose levels?

A- affected; B- affected; C, D, E- not affected

If all of the neural connections from the hypothalamus to the pituitary were severed (cut), the secretion of which of the following hormones would be most affected? Indicate for each hormone whether its secretion would be "affected" or "not affected." A. Vasopressin B. Oxytocin C. Prolactin D. ACTH E. GnRH

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If smooth ER is involved in drug detoxification, do you expect it to play a role in mediating drug tolerance? Why or why not?

A- decrease; B- increase; C- increase

If the adrenal glands were removed from a patient, would you expect an increase or decrease in the plasma levels of the following hormones? A. Cortisol B. ACTH C. CRH

Right, because right you would have a functioning adrenal gland; if it were the left it's adrenal gland would not function properly (sad adrenal)

If you needed a kidney transplant, would you want a left or right kidney?

Because the membrane of the RBC is permeable to urea. Urea can cross into the RBCs thereby increasing the solute concentration inside the cell (meaning low water inside the cell) so water moves down its gradient into the RBC causing it to lyse.

If you place RBCs (0.3m) in a 0.3m solution of urea, the solution is isosmotic to the RBCs but the tonicity will not be isotonic. Why?

white blood cells

Immune cells are _____

a. pyruvic acid

In anaerobic metabolism, the oxidizing agent for NADH (that is, the molecule that removes electrons from NADH) is a. pyruvic acid b. lactic acid c. citric acid d. oxygen

b) moves closer to 0 millivolts

In hyperkalemia, the resting membrane potential a) moves farther from 0 millivolts b) moves closer to 0 millivolts c) remains unaffected

Why are interactions between body-fluid compartments essential for sustaining life? Hint: first you must understand what the body-fluid compartment is (think epithelial cells and basement membranes) to be able to apply its role in survival. You must also know what specific nutrients are being carried by the fluid and their role in tissue health and function.

In order to maintain homeostasis all body-fluid compartments must be able to interact. Our cells receive and release nutrients, oxygen, metabolic waste, signaling molecules, hormones, steroids, and drugs from their extracellular environment by secreting chemical regulators across the plasma membrane. The interstitial fluid is connected with the blood plasma and continuously recycles to and from the blood. If our body-fluids don't interact this can lead to inflammation which could lead to sepsis.

c. oxidative phosphorylation

In terms of the number of ATP molecules directly produced, the major energy-yielding process in the cell is a. glycolysis b. the citric acid cycle c. oxidative phosphorylation d. gluconeogenesis

Explain the consequences of an inadequate dietary intake of iodine.

Inadequate dietary iodine can cause a low production of thyroid hormones because iodine is an essential part of their structure. The person thus has hypothyroidism, with all of the consequences of that condition - slow metabolism, lethargy, coarse, dry skin, and so on. Because of the low levels of thyroid hormones in the blood, there is insufficient negative feedback inhibition of TSH secretion from the anterior pituitary. As a result, there is elevated TSH secretion that causes abnormal growth of the thyroid as a goiter.

Blood Plasma

Interstitial fluid is continuously formed from and returned to the ________.

Passive transport includes all of the non-carrier-mediated processes involving the simple diffusion of ions through membrane channels, nonpolar molecules through the lipid bilayer of the plasma membrane, and water through aquaporin channels, as well as the carrier-mediated process of facilitated diffusion. Passive transport does not require metabolic energy, whereas the membrane carriers of active transport directly or indirectly require ATP to move molecules and ions against their concentration gradients.

List the subcategories of passive transport and distinguish between passive transport and active transport.

Facilitated diffusion, which is diffusion down the concentration gradient requiring the action of carriers, differs from simple diffusion (not involving carriers) in its specificity for the diffusing substance, competition between like substances for a particular carrier, and the ability of a carrier to reach saturation, where the transport rate levels off when the diffusing substance reaches a certain concentration.

List the three characteristics of facilitated diffusion that distinguish it from simple diffusion.

Multiple Organ Dysfunction

MODS

Multiple Organ Failure

MOF

helper T lymphocytes; lymphocytes

Macrophages activate cells labeled A ___ which in turn activate cells labeled B ___.

1-D;2-E; 3- B;4-A; 5-C

Match the antibody type to its function or its characteristic feature: 1. IgA 2. IgD 3. IgE 4. IgG 5. IgM A. Most common type in the plasma B. Involved in immediate hypersensitivity reactions C. B cell receptor hat is secreted during primary response D. Main antibody type in external secretions E. B cell receptor but not secreted

1. C; 2. A; 3. D; 4. B

Match the autoimmune disease to its correct description: 1. Graves' Disease 2. Multiple Sclerosis 3. Myasthenia Gravis 4. Type I Diabetes Mellitus A. myelin sheath B. beta cells in pancreatic islets C. TSH receptor D. acetylcholine receptors

1. d; 2. c; 3. a; 4. b

Match the concentrations of Na+ and K+ inside and outside the cell membrane: 1) K+ outside 2) K+ inside 3) Na+ inside 4) Na+ outside a) 12 mM b) 145 mM c) 150 mM d) 5 mM

1.X; 2. X; 3. Y; 4. Z

Match the following statements to the letters in the Venn diagram: 1. Linked to hypothalamus via portal vessel ____. 2. Is acted upon by somatostatin ____. 3. Release hormones to peripheral target cells ____. 4. Linked by a neural tract ____.

Deep Inside

Medulla

tryptophan; serotonin

Melatonin is made from the amino acid A called ____________ which is converted to a biogenic amine called ____________.

c) Facilitated diffusion.

Molecule X is a large protein, present in higher concentration in the extracellular fluid (ECF) than in the intracellular fluid (ICF). Which of the following is the most likely means of getting molecule X from the ECF to the ICF? a) Primary active transport. b) Secondary active transport. c) Facilitated diffusion. d) Ligand-Gated ion channel.

Describe the common characteristics of hormones and neurotransmitters.

Neurotransmitters and hormones are regulatory molecules that act on target cells by binding to specific receptor proteins. This causes specific changes in the target cells, and these effects are terminated by the removal of the regulatory molecule. The only difference between neurotransmitters and hormones is that neurotransmitters are released into a synaptic cleft, whereas hormones are released into the blood. Indeed, the same molecule (such as norepinephrine) can act as either a neurotransmitter or a hormone.

C. structures shared by many classes of microbes that are not present on host cells.

Pathogen associated molecular patterns (PAMP)s are A. a group of microbicidal enzymes released by the phagocytes. B. membrane receptors that are able to detect microbial products. C. structures shared by many classes of microbes that are not present on host cells. D. toll-like receptors.

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People who are starving have very thin arms and legs. Because they're not eating, no glucose is coming in from the gastrointestinal tract, yet the brain must still be getting glucose from the blood

b) 300 mOsm

Plasma has an osmolality of about 300 mOsm. The osmolality of isotonic saline is equal to a) 150 mOsm b) 300 mOsm c) 600 mOsm d) none of these

Describe the chemical nature of prostaglandins. List some of the different forms of prostaglandins and describe their actions.

Prostaglandins are twenty-carbon long fatty acids containing a five-membered carbon ring. They are members of the eicosanoids because they are derived from the precursor molecule arachidonic acid. Different forms of prostaglandins inclue PGI2, which causes vasodilation and platelet aggregation; PGE2, which causes smooth muscle relaxation and vasodilation, PGF2α, which causes smooth muscle contraction and vasoconstriction; and thromboxane A2, which causes platelet aggregation and vasoconstriction.

E→ B→ C→ A→D

Rearrange the following mechanism of hormone action in the correct order: A. translation B. hormone-receptor complex binds to DNA C. transcription D. synthesis of a desired protein E. hormone binds to intracellular receptor

B → C → D → A → E

Rearrange the following steps involved in an allergic response in the correct order: A. Release chemical mediators B. antigen exposure C. antibodies produced D. antibodies bind to receptors on the surface of mast cells E. allergic reaction.

C→ E→ D→ B→ A

Rearrange the steps in the action of insulin in the uptake of glucose: A. Facilitated diffusion by GLUT4 proteins B. Translocation of intracellular vesicles C. Insulin binds to its receptor D. Activation of the intracellular vesicles containing GLUT4 proteins E. Phosphorylation of insulin receptor

1) directly from one cell to another (because their plasma membranes are very close together and their cytoplasm is coupled) (continuous via gap junctions) (ions and regulatory molecules can diffuse through) 2) released into extracellular environment via a) paracrine; b) synaptic; and c) endocrine (most signals are through these mechanisms

Signals between cells can travel via what methods?

???

State the advantages and disadvantages of the lactic acid pathway.

Explain how stress affects the secretions of the adrenal cortex and medulla. Why does hypersecretion of the adrenal medullary hormones make a person more susceptible to disease?

Stress stimulates the secretion of ACTH, which then stimulates the adrenal cortex to increase its secretion of the glucocorticoids. Depending on the stressor, stress can also activate the sympathoadrenal system and thereby cause the medulla to increase its secretion of epinephrine and norepinephrine. Because these hormones increase the breakdown of the body's energy reserves of glycogen and fat, the person could become more susceptible to disease. Also, the immunosuppressive effects of the glucocorticoids could prevent the body from adequately combating infections and tumors.

Extracellular Matrix: Clinical Application

Study that she was involved in... -- involved in the pathogenesis of degenerative joint disease -- required for normal tissue remodeling and macrophase migration during infection -- but if overexpressed then it destroys cartilage -- MMPs are required normally for tissue remodeling (wear and tear). Can run rampant and can break down tissue.

???

Suppose a drug is developed that promotes the channeling of H+ out of the intermembrane space into the matrix of the mitochondria of adipose cells. How could this drug affect the production of ATP, body temperature, and body weight?

d) all of these

Suppose that gated ion channels for Na+ or Ca2+ opened in the plasma membrane of a muscle cell. The membrane potential of that cell would a) move toward the equilibrium potential for that ion b) become less negative than the resting membrane potential c) move farther away from the potassium equilibrium potential d) all of these

C. Thymus (that is why they are called T-cells)

T cells mature in the A. Lymph Nodes B. Spleen C. Thymus D. GALT

Describe the embryonic origins of the adenohypophysis and neurohypophysis, and list the parts of each. Which of these parts is also called the anterior pituitary? Which is called the posterior pituitary?

The adenohypophysis is derived from oral epithelium and consists of the pars distalis, or anterior pituitary, and the pars tuberalis, which partially wraps around the infundibulum. The neurohypophysis is derived from a downgrowth of the brain and consists of the pars nervosa, also known as the posterior pituitary.

List the categories of corticosteroids and identify the zone of the adrenal cortex that secretes the hormones within each category.

The adrenal cortex secretes mineralocorticoids (mainly aldosterone), glucocorticoids (mainly cortisol), and adrenal androgens (mainly dehydroepiandrosterone). The mineralocorticoids are secreted by the zona glomerulosa, whereas the glucocorticoids and adrenal androgens are secreted by the zona fasciculate and zona reticularis.

Identify the hormones of the adrenal medulla and describe their effects.

The adrenal medulla secretes mainly epinephrine, with lesser amounts of norepinephrine. These have sympathoadrenal effects: increased heart rate, dilation of coronary blood vessels, and so on. They also have metabolic effects, increasing metabolic rate and causing a breakdown of liver glycogen and stored fat to increase the blood levels of glucose and fatty acids, which are effects that aid the "fight-or- flight" reaction.

1) Adenylate Cyclase (AC) (cAMP and cGMP) 2) Phospholipase C (PLC) (DAG and IP3) 3) Tyrosien Kinase (RTK)

What are the three possible second messenger mechanisms?

1) Innate Defenses 2) Adaptive Immunities -- these are the two arms of the immune system

What are the two host defense mechanisms?

E. the type of the constant region of the heavy chains.

The antibody type is determined by A. its function. B. the structure of its light chains. C. the type of light chains. D. the structure of its variable regions. E. the type of the constant region of the heavy chains.

a. the liver

The conversion of glucose 6-phosphate to free glucose, which can be secreted into the blood, occurs in a. the liver b. skeletal muscles c. both a and b

c. both a and b

The conversion of glycogen to glucose 6-phosphate occurs in a. the liver b. skeletal muscles c. both a and b

e. in both b and c

The conversion of lactic acid to pyruvic acid occurs a. in anaerobic respiration b. in the heart, where lactic acid is aerobically respired c. in the liver, where lactic acid can be converted to glucose d. in both a and b e. in both b and c

Describe the structure of the endocrine pancreas. Which cells secrete insulin and which secrete glucagon?

The endocrine portion of the pancreas is in the form of tiny islands - the pancreatic islets or islets of Langerhans - embedded within the larger exocrine portion of the pancreas. The islets consist of different cell types that secrete different hormones. The beta cells secreted insulin and the alpha cells secrete glucagon.

List some of the paracrine regulators produced by blood vessels and describe their actions. Also, identify specific growth factors and describe their actions.

The endothelium of blood vessels produces nitric oxide and bradykinin, which promote vasodilation, and endothelin-1, which promotes vasoconstriction. Growth factors are paracrine regulators that promote growth and cell division. An example is nerve growth factor, which is also classified as a neurotrophin.

Lactic Acid Dehydrogenase (LDH)

The enzyme responsible for converting lactic acid to pyruvate is ____?

Extracellular Matrix; Protein Fibers; Ground Substance

The extracellular material of the connective tissue is called ________ which is made of ______ and ______.

C. cytotoxic T cells.

The following are the components of the innate immunity except A. plasma proteins. B. natural killer cells. C. cytotoxic T cells. D. epithelial barriers. E. phagocytes.

d. gluconeogenesis

The formation of glucose from pyruvic acid derived from lactic acid, amino acids, or glycerol is called a. glycogenesis b. glycogenolysis c. glycolysis d. gluconeogenesis

Explain how the response of the body to a given hormone can be affected by the concentration of that hormone in the blood.

The hormone must be present within a normal concentration range to have its normal, physiological effect; abnormally high concentrations can produce abnormal effects. Hormones can have priming effects, where bursts of hormone secretion can cause the upregulation of receptor numbers in the target tissues. Prolonged exposure to high concentrations of a hormone can desensitize the tissue, causing downregulation of receptor numbers. This is normally prevented by the pulsatile secretion of certain polypeptide hormones.

List the hormones secreted by the anterior pituitary and explain how the hypothalamus controls the secretion of each.

The hormones of the anterior pituitary are growth hormone, TSH, ACTH, FSH, LH, and prolactin. These are produced within the anterior pituitary and secreted in response to releasing hormones secreted by the hypothalamus into the hypothalamo-hypophyseal portal system. These releasing hormones are GHRH, TRH, CRH, and GnRH, which stimulate the anterior pituitary secretion of growth hormone, TSH, ACTH, and the gonadotropins (FSH and LH), respectively. Additionally, the hypothalamus secretes somatostatin and a prolactin-inhibiting hormone (dopamine), which inhibit the anterior pituitary secretion of growth hormone and prolactin, respectively.

c) simple diffusion through membrane channels

The movement of water across a plasma membrane occurs by a) an active transport water pump. b) a facilitated diffusion carrier. c) simple diffusion through membrane channels. d) all of these.

b. 2; 30

The net gain of ATP per glucose molecule in lactic acid fermentation is ____; the net gain in aerobic respiration is generally ____. a. 2; 4 b. 2; 30 c. 30; 2 d. 24; 38

Describe the location of the pineal gland and discuss the possible functions of melatonin.

The pineal gland is located on the roof of the third ventricle in the diencephalon of the brain. The pineal hormone melatonin is know to influence the pituitary-gonad axis in many mammals, and it may have an antigonadotropic effect in humans involved in timing puberty but this is controversial. Melatonin secretion rises at night and falls during the day, and so follows a circadian rhythm that may affect circadian activity in different organs of the body.

A. opsonization.

The process of coating microbes to facilitate phagocytosis is called A. opsonization. B. adhesion. C. activation. D. migration.

a) Facilitated diffusion.

The rate of absorption of a drug taken orally is found to increase as the dose is increased up to a point where further increase in dose has no further increase in the rate of absorption. Which of the following processes best describes the drug absorption? a) Facilitated diffusion. b) Primary active transport. c) Simple diffusion. d) Secondary active transport.

c) somewhat less negative than the potassium potassium equilibrium potential

The resting membrane potential of a neuron or muscle cell is a) equal to the potassium equilibrium potential b) equal to the sodium equilibrium potential c) somewhat less negative than the potassium potassium equilibrium potential d) somewhat more positive than the sodium equilibrium potential e) not changed by stimulation

Explain how the secretions of the adrenal cortex and adrenal medulla are regulated.

The secretions of the adrenal cortex are controlled by hormones. ACTH from the anterior pituitary stimulates the secretion of the glucocorticoids from the adrenal cortex, for example. The secretion of epinephrine and norepinephrine from the adrenal medulla is stimulated by nerve axons. Preganglionic sympathetic axons innervate the adrenal medulla and stimulate it to secrete its hormones during the fight-or-flight reaction.

Immunology

The study of the body's second and third lines of defense ______.

Explain how the gonadal and placental hormones are categorized and list the hormones secreted by each gland.

The testes secrete androgens, or male hormones, and the primary androgen is testosterone. The ovaries secrete estrogens, primarily estradiol, and progesterone. The placenta secretes estrogens and progesterone, which are sex steroid hormones. However, the placenta also secretes some polypeptide hormones. These include human chorionic gonadotropin, which is similar to LH, and somatomammotropin, which is similar to both growth hormone and prolactin.

Describe how thyroid hormones are produced and how their secretion is regulated.

The thyroid actively transports iodide from the blood into the follicles, where it is oxidized and bound to thyroglobulin within the colloid. From that, monoiodotyrosine and diiodotyrosine are used to produce the thyroid hormones T4 and T3, still bound to thyroglobulin. In response to stimulation by TSH, this is taken into the follicular cells by endocytosis, where the hormones are cleaved from thyroglobulin and secreted into the blood. In the blood, the hormones are transported bound to a binding globulin.

Describe the structure of the thyroid gland and list the effects of thyroid hormones.

The thyroid, located just below the larynx, has two lobes. Each contains many microscopic hollow sacs called thyroid follicles. The follicular cells secrete the thyroid hormones thyroxine (T4) and triiodothyronine, which act on most cells of the body to increase the basal metabolic rate. Parafollicular cells between the thyroid follicles secrete calcitonin, which acts to lower the blood Ca2+ concentration.

Paracrine

The use of a chemical messenger to transfer information from one cell type to another cell type within a single tissue is referred to as _____ signaling.

List the hormones released by the posterior pituitary. Where do these hormones originate and how are their secretions regulated?

There are two hormones secreted by the posterior pituitary, both produced by neuron cell bodies in the supraoptic and paraventricular nuclei of the hypothalamus. These are transported by axons to the posterior pituitary for storage and later release. Antidiuretic hormone (ADH), also called arginine vasopressin, is secreted in response to stimulation of osmoreceptor neurons in the hypothalamus by a rise in plasma osmolality. Oxytocin secretion is stimulated by a neuroendocrine reflex in response to the suckling of a baby.

Describe the location of the parathyroid glands and the actions of parathyroid hormone.

There are usually four parathyroid glands embedded in the posterior surface of the lateral lobes of the thyroid gland. They secrete parathyroid hormone (PTH), which acts to raise the blood concentration of Ca2+ by stimulating the dissolution of calcium phosphate crystals in bone and the renal reabsorption of Ca2+. This helps to maintain homeostasis of the plasma Ca2+ concentration when those levels start to decline.

Explain the nature and actions of the receptor proteins for insulin and the growth factors.

These receptor proteins also act as a tyrosine kinase enzyme. When the ligand (insulin or a growth factor) binds to the alpha subunits of the receptor, the beta subunits autophosphorylate each other and thereby become more active enzymes. This active enzyme then phosphorylates substrate molecules, leading to phosphorylation of signaling molecules. In the case of insulin, some of these activated signaling molecules promote the insertion of transport carrier proteins for glucose into the plasma membrane, so that the cell can remove insulin from the blood.

b) Potassium.

This ion is primarily responsible for maintaining the resting membrane potential of excitable cells. a) Sodium. b) Potassium. c) Chloride. d) Protein. e) Calcium.

Steroid Hormones

Thyroid hormones act like _____?

Multilevel Network

To protect the body against pathogens, the immune system relies on a ______ of physical barriers, immunologically active cells, and a variety of chemicals.

1) steroids 2) amines 3) polypeptides 4) glycoproteins

What are the four chemical categories of hormones?

???

What purpose is served by the formation of lactic acid during anaerobic metabolism? How is this accomplished during aerobic respiration?

These pumps are constantly active to maintain the concentrations of Na+ and K+ on the two sides of the plasma membrane. This action is required because the resting membrane potential is slightly less negative than the K+ equilibrium potential, and far more negative than the Na+ equilibrium potential. The pumps also contribute to the membrane potential because they pump out 3 Na+ for every 2 K+ they pump into the cell.

What role do the Na+/K+ pumps play in establishing the resting membrane potential?

???

What three molecules serve as the major substrates for gluconeogenesis? Describe the situations in which each one would be involved in this process. Why can't fatty acids be used as a substrate for gluconeogenesis? (hint: Count the carbons in acetyl CoA and pyruvic acid.)

d. all of these occur.

When amino acids are used as an energy source, a. oxidative deamination occurs. b. pyruvic acid or one of the Krebs cycle acids (keto acids) is formed. c. urea is produced. d. all of these occur.

Acetyl CoA enters Lipogenesis

When energy is in excess it does what?

Principle of Energy Storage

When more food energy is taken into the body than is needed to meet energy demands, we can't store ATP for later instead... -- glucose is converted into glycogen and fat -- ATP production is inhibited...why?

c. lactic acid

When skeletal muscles lack sufficient oxygen, there is an increased blood concentration of a. pyruvic acid b. glucose c. lactic acid d. ATP

E. ADH.

When stimulated by a particular hormone, there is a marked increase in the activity of a G protein in the membrane. The hormone being studied is probably A. estrogen. B. testosterone. C. T4. D. T3. E. ADH.

Describe the sequence of events by which a hormone can cause a rise in the cytoplasmic Ca2+ concentration and explain how Ca2+ can function as a second messenger.

When the hormone binds to its receptor, G-protein subunits dissociate and travel through the membrane to activate phospholipase C. This enzyme breaks down a phospholipid in the membrane to diacylglyceride and inositol triphosphate (IP3). The IP3 binds to a receptor on the endoplasmic reticulum, triggering its release of stored Ca2+. The Ca2+ acts as a second messenger; it binds to calmodulin, and this complex then activates protein kinase. Active protein kinase phosphorylates proteins, thereby activating or inactivating them to produce the actions of the hormone.

List the terms used to describe hormone interactions and give examples of these effects.

When two or more hormones work together, their effects are synergistic. Examples of synergism include the stimulation of heart rate by epinephrine and norepinephrine, which produce additive effects, and the stimulation of lactation by prolactin and oxytocin (among other hormones), which have complementary effects. A hormone has a permissive effect when it improves the action of a different hormone on a target tissue. An example is the estradiol stimulation of receptor proteins for progesterone within the endometrium. Antagonistic effects of hormones is illustrated by the stimulation of fat synthesis by insulin and of fat breakdown by glucagon.

C. Pancreas.

Which gland is both an endocrine and an exocrine gland? A. Pituitary gland. B. Ovary. C. Pancreas. D. Thyroid gland. E. Pineal gland.

A. Interferons.

Which of the following are important in nonspecific immune defense? A. Interferons. B. Secretion of antibodies. C. Activation of lymphocytes. D. Class-I MHC proteins.

a) The more soluble X is in nonpolar solvents, the more rapidly X diffuses across the membrane.

Which of the following statements about diffusion of substance X across a plasma membrane is true? a) The more soluble X is in nonpolar solvents, the more rapidly X diffuses across the membrane. b) The smaller the molecular weight of X is, the slower its diffusion. c) If X is water, its rate of diffusion across membranes is low. d) If X is water soluble, its diffusion across membranes will be fast even when its molecular weight is large.

C. They have receptors on the cell membrane.

Which of the following statements about peptide or protein hormones is usually true? A. They are not stored in endocrine-producing glands. B. They have longer half-lives than steroid hormones. C. They have receptors on the cell membrane. D. They have a slower onset of action than both steroid and thyroid hormones.

B. Antihistamine is often used to treat the condition.

Which of the following statements is not true of contact dermatitis? A. It is caused by poison ivy. B. Antihistamine is often used to treat the condition. C. Corticosteroids are the best choice of treatment. D. It is mediated by T lymphocytes.

a) are components of the extracellular matrix.

Which of the following statements is not true of integrins? They a) are components of the extracellular matrix. b) serve as adhesion molecules. c) relay signals between the cell and the extracellular matrix. d) impart polarity to the cell.

d) Use magnesium ion as a cofactor.

Which of the following statements is not true of matrix metalloproteinases? a) Important in tissue remodeling. b) Assist in the migration of phagocytic cells during the fight against infection. c) Secreted in their inactive form and activated in the extracellular matrix. d) Use magnesium ion as a cofactor.

b) movement of Na+ and K+ through the action of the Na+ / K+ pumps

Which of these is not an example of cotransport? a) movement of glucose and Na+ through the apical epithelial membrane im the intestinal epithelium b) movement of Na+ and K+ through the action of the Na+ / K+ pumps c) Movement of Na+ and glucose across the kidney tubules d) movement of Na+ into a cell while Ca2+ moves out

b. brain

Which of these organs has an almost absolute requirement for blood glucose as its energy source? a. liver b. brain c. skeletal muscles d. heart

d) the pumps are constantly active in all cells

Which of these statements about the Na+ / K+ pump is true? a) Na+ is actively transported into the cell b) K+ is actively transported out of the cell c) an equal number of Na+ and K+ ions are transorted with each cylce of the pump d) the pumps are constantly active in all cells

b) Carrier proteins in the cell membrane are required for this transport

Which of these statements about the facilitated diffusion of glucose is true? a) There is a net movement from the region of lower to the region of higher concentration. b) Carrier proteins in the cell membrane are required for this transport. c) This transport requires energy obtained from ATP. d) It is an example of cotransport.

d. Both a and b are true.

Which of these statements about the oxygen in the air we breathe is true? a. It functions as the final electron acceptor of the electron transport chain. b. It combines with hydrogen to form water. c. It combines with carbon to form CO2. d. Both a and b are true. e. Both a and c are true.

d) all of these are true

Which of these statements comparing a 0.5 m NaCl solution and a 1.0 m glucose solution is true? a) they have the same osmolality b) they have the same osmotic pressure c) they are isotonic to each other d) all of these are true

a) it can occur as a result of dehydration

Which of these statements regarding an increase in blood osmolality is true? a) it can occur as a result of dehydration b) it causes a decrease in blood osmotic pressure c) it is accompanied by a decrease in ADH secretion d) all of these are true

b) it is used for cellular uptake of blood glucose

Which os these statements about carrier-mediated facilitated diffusion is true? a) it uses cellular ATP b) it is used for cellular uptake of blood glucose c) it is a form of active transport d) none of these are true

B. Natural killer cells.

Which particular cell type or a product of the innate immune system contributes to protection against tumor? A. Killer T cells. B. Natural killer cells. C. Helper T cells. D. Antibodies.

???

Why do skeletal muscles, the liver and heart prefer to use fatty acids? Does this make sense considering their function and rate of usage by us?

???

Why is the production of lactic acid termed a "fermentation" pathway?

Because we would end up producing physiological responses that are not needed and this could cause disease

Why would we not want every ligand to bind to every receptor?

True

Will diffusion occur without a physical separation or across a permeable membrane?

Secondary; primary

__________ response is rapid and more efficient that the __________ response which takes 5-10 days before measurable amounts of antibodies appear in the blood.

Mechanism of Steroid Hormone Action - Non-Genomic Action

cell surface receptors (why? because the cell receptor is at the cell surface) -- nuclear hormones are in the nucleus, bind and are ready to go -- may occur in the cytoplasm and involve second-messenger systems -- may cause effects in seconds to minutes, much faster than expected -- IMAGE: (from left to right) ligand-gated ion channel receptors, G-protein coupled receptor, tyrosine kinase receptors, integrins, toll-like receptors

Draw a flow diagram below that connects the concepts of low plasma cortisol levels, level of glucocorticoid receptor expression, degree of cortisol catabolism and ending with the end physiological outcome of increased/decreased (choose one) vulnerability to stress.

decreased cortisol in blood ---> decreased glucocorticoid release from adrenal cortex ---> decrease in stress response Dr. CC: chronic stress --> low cortisol levels --> high vulnerability to stress --> decrease breakdown of cortisol --> increased + 1/2 of cortisol --> cortisol receptor expression is high --> increased sensitivity --> cortisol rest / relaxation

Liver

glucose and ketone bodies come from where?

symport

moving two molecules in the same direction