202 Lecture Exam 1 Flashcards
What stimulates glucocorticoids?
ACTH and blood volume
What is NIDDM?
Type 2 Diabetes Mellitus
Which hormones are water-soluble amino acid polymers?
Peptide hormones
Which form of diabetes causes sugar build up in the urine?
Diabetes mellitus
Which form of Diabetes Mellitus is autoimmune?
Type 1
How many cell proteins can one hormone affect?
Thousands
If someone has no beta islets in their pancreas, what condition are they suffering from?
IDDM (type 1)
What do steroid hormones do once inside the cell?
Combine with nuclear or cytoplasmic receptors and bind to chromosomes and activate gene transcription
What are the three types of hormone release mechanisms?
- Endocrine system - adrenal cortex releasing hormones after stimulation by ACTH
- Humoral control system - PTH based on blood calcium
- Neural control system - nerves trigger release of hormones (ex. nerve impulses to adrenal medulla trigger epinephrine)
What defines a target tissue?
Hormone receptors
What causes Type 2 diabetes?
Loss of insulin receptors on cells, so glucose can’t enter
What do Gonadocoticoids eventually become?
Estrogen and Testosterone
Why does excessive beer consumption trigger gynecomastia?
Xenoestrogens in hops
Which thyroid hormone determines your energy?
T3
What are xenoestrogens?
Estrogens from outside sources
How do the paracrine and endocrine systems differ from neurotransmitters?
Neurotransmitters use hormones to stimulate action potentials in the nervous system, they are part of the nervous system
What are two examples of steroid hormones?
Cortisol and Testosterone
Where is the production of estrogen in pre-menopausal versus post-menopausal women?
Pre-menopause: ovaries and adrenal cortex
Post-menopause: adrenal cortex
Which hormone is derived from cholesterol and lipid soluble?
Steroid hormones
What is a target tissue?
A tissue that possesses specific receptors which bind to a given hormone
Why would high TSH levels indicate a low-functioning thyroid?
Thyroid would compensate for low function by triggering more TSH; hypothalamus initiates loop but T4 isn’t made
Epinephrine and Dopamine are what kind of hormone?
Amine
What is the role of estrogen in breast cancer?
Fuels some types of it
What are the symptoms of diabetes mellitus?
Polyuria (excess urination), polyphagia (excess eating), polydypsia (excess hunger and thirst), sugar in urine
What is the significance of steroid hormones being fat-soluble?
They can diffuse through the cell surface
What kind of hormone are ADH and Oxytocin?
Peptide
Are amine hormones water soluble?
Yes
To what do amine and peptide hormones have to bind?
Cell membrane receptors
What are symptoms of hypothyroidism?
Weight gain, fatigue, low body temperature, dry skin, constipation
What would happen if you gave AI to a pre-menopausal woman?
It would not work. AI would not inhibit the main source of estrogen coming from the ovaries
What drug is used to block estrogen in some forms of breast cancer?
Aromatase inhibitor (AI)
What controls the release of thyroid hormone?
Negative feedback from blood concentration of T4
What is the humoral control system?
It involves changes in the blood triggering the release of certain hormones
If T4 is high, what does the thyroid do?
Produces less TSH and TRH
If T4 is high, what does the thyroid do?
Produces more TSH and TRH
What are the symptoms of diabetes insipidus?
Excessive urination, unsweet urine
Which part of the pituitary synthesizes and stores its own hormones?
Anterior pituitary
What is the name of corticoids that increase blood glucose?
Glucocorticoids (like cortisol)
How is acromegaly different from pituitary gigantism?
Pituitary gigantism = too much GH in childhood
Acromegaly = excess GH in adulthood - large jaw and hands, but can’t grow taller
What is the pancreas releasing insulin or glucagon an example of?
Humoral control system
Why are there more hormones to increase blood sugar than to decrease it?
You can live with high blood sugar indefinitely, but low blood sugar kills you in minutes because every system in the body uses glucose
What is formed by the axons of neurosecretory cells that originate in the hypothalamus?
The hypothalamo-hypophyseal tract
What would happen to ghrelin levels if a person receives an atropine injection?
Ghrelin inhibited, wouldn’t feel hunger, block parasympathetic nervous system
What does the binding of hormones to a cell membrane receptor trigger?
G-protein pathway, secondary messenger, cell response
What does the conversion of T4 to T3 require?
Minerals
What can increase the concentration of a hormone in the blood?
Stimulation of an endocrine gland
What causes diabetes mellitus?
Prolonged elevated blood glucose
What are the end products of steroid hormones working in cells?
mRNA and new proteins
What is aromatization?
The conversion of male hormones into female hormones using aromatase (enzyme)
What is the name of corticoids that are stimulated by ACTH and low blood volume and reabsord Na+ and water?
Mineralocorticoids (including aldosterone)
What is IDDM?
Type 1 Diabetes Mellitus (Insulin Dependent DM)
Which 3 minerals does the body need to make T3?
Zinc, Selenium, and Copper
What two things determine specificity on a target tissue?
Presence of absence of receptor and location of receptor
Explain the composition of the posterior pituitary
Made of axons from the hypothalamus, myelinated neurons, store the hormones made in the hypothalamus
What are some of the side-functions of oxytocin?
Milk letdown, trust, bonding
What is it called when the activation of one protein activates several others in a chain reaction?
Amplification
Is prostate cancer caused by excess testosterone?
No, excess DHT causes it, but testosterone does not
What are Gonadocorticoids?
steroid hormones, stimulated by ACTH, aid in sex characteristic developement
What is the classification of atropine?
Cholinergic antagonist
What is the name of steroids and androgens produced in the adrenal medulla?
Corticoids
What is the difference between paracrine and endocrine hormones?
Paracrine hormones act on neighboring cells, localized
Endocrine releases hormones into the blood to circulate to intended target
What are some examples of xenoestrogens?
plastic bottles, beef, eggs, milk, soy, flax, hops
What regulates anterior pituitary hormone production?
Hypothalamus
When hormones modify amino acids, what are formed?
Amine hormones
Which form of diabetes is caused by loss of ADH secretion?
Diabetes insipidus
What is plasma?
The clear liquid left when the formed elements are taken from the blood
What is blood plasma made of?
Mostly water but also solutes made of protein (albumin)
What are formed elements?
RBC, WBC, and platelets
What is the structure and function of erythrocytes?
biconcave disc, no nuclei; transport most oxygen and some CO2
What is the structure and function of Leukocytes?
S: round or slighly indented, larger than RBC, varies depending on type
F: mediate immune responses involving antigens
What is the structure and function of platelets?
S: small cell fragments with many vesicles but no nucleus
F: form platelet plug, release chemicals that promote vascular spasm and blood clotting
Which leukocytes are granular?
Neutrophils, eosinophils, basophils
Which leukocytes are agranular?
Monocytes, lymphocytes
What are the three types of protein found in the plasma and what are their general functions?
- Albumin: transport solutes, buffer pH, change viscosity and osmolarity
- Globulins: Solute transport, clotting, immunity
- Fibrinogen: fibrin precursor (protein that forms framework of blood clot)
What is polycythemia?
Cancer of erythropoietic line of red bone marrow, hight RBC count
What is leukopenia?
Low WBC count
What is leukemia?
Cancer of hemopoietic tissues, too many leukocytes and their precursors
What is anemia?
Not enough RBC
What is thrombocytopenia?
A dangerous platelet deficiency
What is thrombocytosis?
Too many platelets
Which form of anemia is caused by a lack of iron intake or slow bleeding?
Iron-deficiency anemia
Which form of anemia is caused by a lack of B12 or folic acid?
Pernicious anemia
What is anemia caused by chronic inflammation such as arthritis or gastritis?
Anemia of chronic inflammation
Which form of anemia is caused by heavy bleeding?
Hemorrhagic anemia
What is aplastic anemia?
Anemia due to damage to bone marrow when the red blood cells are made
What can cause aplastic anemia?
Chemotherapy and radiation
What are the defining characteristics of microcytic anemia?
Small RBCs
What kind of anemia are iron-deficiency and hemorrhagic?
Microcytic anemias
What kind of anemia is pernicious anemia?
Macrocytic anemia (large RBCs)
What is a reticulocyte?
the precursor to erythrocytes
When would many reticulocytes be found in the body?
When many RBCs are being made in the bone marrow to replace lost RBCs, such as in hemorrhagic anemia
What is the lifespan of a erythrocyte?
Develop to maturity in 7 days, live 120 days
How does a erythrocyte die?
Its membrane wears down, it goes to the spleen and liver which phagocytize it and send bilirubin and iron back into circulation or out through the stools or urine
What determines the formation of new RBCs?
increase in altitude or blood loss
What causes formation of new WBCs?
infection or cancer
What are the four different types of leukemia?
- Acute Myeloblastic Leukemia (AML)
- Chronic Myeloblastic Leukemia (CML)
- Acute Lymphocytic Leukemia (ALL)
- Chronic Lymphocytic Leukemia (CLL)
Which forms of leukemias involve any of the WBCs except lymphocytes?
Myelocytic (neutrophils, eosinophils, basophils, monocytes)
Where do t cells mature?
Thymus
Where do B cells mature?
Bone marrow
What is hemostasis?
A sequence of responses that stops bleeding
What are the two mechanisms of hemostasis?
Vascular spasm and platelet plug formation
What is vascular spasm?
When arteries or arterioles are damaged and the circularly arranged smooth muscle in their walls contracts immediately
What three things can cause vascular spasm?
- Smooth muscle damage
- Substance release from other platelets
- Reflexes from pain receptors
How long does vascular spasm last?
A few minutes to a few hours while other mechanisms kick in
What are the three steps of platelet plug formation?
- Platelet adhesion - contact and stick to damaged vessel
- Degranulation - platelets extend projections and interact, release ADP and throboxane A2 to activate other platelets
- Platelet Plug ft. Platelet Aggregation - ADP makes platelets stick to each other, mass forms, prevents blood loss
What is platelet plug formation an example of?
Positive feedback
How is Thrombin formed?
Prothrombin activator converts Prothrobin into Thrombin
What is thrombin?
An enzyme
What role does Thrombin play in coagulation?
It converts Fibrinogen to Fibrin and helps Fibrin mesh to trap blood cells and seal holes
Which mineral plays a crucial role in blood clotting?
Calcium
How are blood clots dissolved?
They are dissolved by the fibrinolytic system
What is the role of plasminogen in dissolving blood clots?
It is activated by blood enzymes to become plasmin, which digests the fibrin threads
Which factors of a clot does plasmin digest?
Fibrinogen, prothrombin, and V and XII factors
What is heparin?
Anticoagulants produced by mast cells and basophils
What two anticoagulants block thrombin?
Heparin and antithrombin
How does Warfarin work and what does it do?
Antagonistic to vitamin K to stop synthesis of 4 clotting factors; anticoagulant
Is Warfarin or Heparin faster at preventing inappropriate coagulation?
Heparin
What makes blood red?
Iron in the middle of the heme group
Scientific name for too many cells
Cytosis
Name for not enough cells
-penia
Name for something related to blood
-emia
What two things would occur if hemoglobin were reduced?
- microcytic = cells get smaller
2. hypochromatic = less color
Why do iron pills often fail to help anemia?
No always iron-deficiency anemia; ID anemia and ACI look the same
What are the three precursor cells for red blood cells?
Stem cell, erythroblast, and reticulocyte
What is erythropoeisis?
Production of red blood cells
What activates erythropoeisis?
Erythropoietin
What negative side effect can tooth infections cause?
Endocarditis
Describe the pericardium
Fibrous pericardium Parietal pericardium (outer layer of serous membrane) Visceral pericardium (inner layer of serous membrane)
What is another name for the visceral layer of the pericardium?
Epicardium
What is the structure and function of the epicardium?
Thin, transparent, slippery; allows heart to pump smoothly
What is the name, structure, and function of the middle layer of the heart?
Myocardium; muscle; pumps
What is the name, structure, and function of the inner layer of the heart?
Endocardium; smooth lining; covers valves
What do valve defects do in the heart?
Cause blood to regurgitate back into the ventricles, making the ventricles contract harder to overcome the pressure
What are the two circuits of circulation?
Pulmonary circuit and systemic circuit
What part of the heart does the right coronary artery serve?
right atrium and both ventricles
What part of the heart does the left coronary artery serve?
Left atrium and both ventricles
What is coronary artery disease (CAD)?
Build up of plaque in arteries that slows blood flow, sometimes stopping it
What composes the plaque in CAD?
Fats, cholesterol, calcium, blood substances
If complete blockage of an artery occurs, what is the outcome?
Myocardial infarction
Describe the 5 steps of the intrinsic conduction system of the heart
- SA node - electrical pacemaker, self-depolarizes
- AV node - allows current to ventricles
- Bundle of His - carries AV node signals
- Bundle branches - travels down interventricular septum
- Purkinje fibers - allow myocytes of ventricles to receive electrial stimulation
Which node in the heart depolarizes more frequently?
SA node (70-80 bpm)
If both nodes were lost, what system would kick in?
Ventricular walls would try to generate their own action potentials (20-40 bpm), death would occur
What is the role of the AV nodal delay in coordinating cardiac systole?
Allows both atria to complete their contraction and empty into ventricles completely before the ventricles contract
What two places does calcium need to come from in order for muscle contraction to occur?
Outside the cell sarcolemma and from the sarcoplasmic reticulum
What is the cardiac muscle refractory period?
250 msec
Why is the cardiac refractory period longer than that of skeletal muscles?
Prevents tetany
How is the cardiac refractory period maintained?
Slow entry of calcium into muscle cell, allows movement of potassium outside the cells (maintains voltage and depol longer)
What does the P wave correspond to in the heart?
Atrial depolarization
What is systole?
contraction
On an EKG what corresponds to the QRS complex?
Ventricular depolarization and systole
What is the T wave on an EKG?
Ventricular repolarization
What is the end-diastolic volume?
The volume of blood remaining in the ventricle at the end of its relaxation period
What is the end-systolic volume?
The volume of blood remaining in each ventricle at the end of systole
How do you calculate stroke volume (SV)?
SV = EDV - ESV
What is the name of the volume of blood ejected from the left or right ventricle into the aorta or pulmonary trunk each minute?
Cardiac Output
How do you calculate Cardiac Output?
CO = SV(mL/beat) x HR (beats/min)
How does the autonomous nervous system influence cardiac output?
Sympathetic - increases (more depol at SA node, more norepinephrine, more beating)
Parasympathetic - decreases (through vagus nerve, less depol at SA and AV)
Does the sympathetic or parasympathetic nervous system affect myocardium contractility?
Sympathetic
What is the Frank-Starling Law of the heart?
It states that the stroke volume is proportional to the EDV
What is the general principle behind the Frank-Starling law?
The more blood filling a ventricle during diastole, the stronger it will contract
What is preload?
The amount of tension in the ventricular myocardium directly prior to contraction
What is the structure and function of the Tunica adventitia?
S: elastic and collagen fibers
F: protect and reinforce vessels and anchor it to surrounding structures
WHat is the structure and function of the Tunica media?
S: smooth muscles and elastic fibers
F: constrict or dilate to change lumen diameter
What is the structure and function of the Tunica intima?
S: Lining of endothelium, basement membrane, internal elastic lamina
F: In contact with blood in lumen, can have pores in capillaries
What is the role of LDL and macrophages in the the development of atherosclerotic plaques?
Cholesterol eats the free radicals and becomes ox-LDL, which macrophages eat, become foam cells; foam cells, macrophages, and T cells form beginning of plaque
Which capillaries are found in most tissues?
Continuous capillaries
In continuous capillaries, what allows small solutes to pass through?
Intercellular clefts
Which kind of capillaries are found in the kidneys or the small intestine?
Fenestrated capillaries
What is a sinusoid capillary?
Irregular capillaries that conform to the shape of the tissue that it is around, twisted with no basal lamina, huge gaps
Where are sinusoid capillaries found?
LIver, bone marrow, spleen, and other organs
What is the name of the rate at which blood flows through a certain tissue in a certain amount of time?
Flow rate
What is the blood pressure gradient?
The idea that blood follow the pressure gradient from greater to lower pressure
If the pressure difference of blood is great, what will the flow rate do?
Increase
Greater blood resistance leads to …?
smaller blood flow
What is resistance (as relates to blood)?
Opposition to the blood flow caused by friction between the blood and the walls of the blood vessels
What are three factors responsible for resistance?
- size of lumen
- viscosity of blood
- length of blood vessel
In vasoconstriction, what happens to blood flow?
smaller blood flow
What state does a vein need to be in to stimulate blood flow?
Vasodialation
How does the systemic vascular resistance effect the blood pressure measurement?
narrowed blood vessels make the heart pump harder and the blood pressure increase
What is vasoconstriction?
The autonomic nervous system causing the smooth muscles in the tunica media to contract
What is the term for lack of oxygen to a tissue?
Ischemia
What is angina?
Pain
What is ischemia at the legs due to a blockage of blood flow?
Intermittent claudication
What is an aneurysm?
A bulge in the walls of an artery due to weak wall
What is the function of the hepatic portal system?
Direct blood from GI tract to liver for processing to protect the body from harmful substances
What is vascular tone and what is its function?
The degree of constriction experienced by a blood vessel relative to its maximally dilated state; regulates arterial blood pressure
What is the relationship between cross-sectional area and velocity?
Velocity of blood flow is inversely related to the cross-section
Why is blood velocity low in capillaries?
To keep from bursting the delicate capillaries
What is the definition of filtration and what two pressures promote it?
Pressure driven movement of fluid from blood capillaries into interstitial fluid; BHP and IFOP
What is re-absorption and what two pressures promote re-absorption?
Pressure driven movement of fluid/solutes from interstitial back into blood capillaries; BCOP and IFHP
What is hydrostatic pressure?
The pressure of water in blood plasma exerting against blood vessel walls
What does BHP do in the body?
Pushes fluid out of capillaries into interstitial fluid
What does IFHP do in the body?
Pushes fluid from interstitial spaces back to capillaries
What is osmotic pressure?
The pulling power of proteins in blood plasma
What does BCOP do in the body?
Pulls fluid from interstitial spaces to capillaries
What does IFOP do in the body?
Pulls fluid from capillaries into the interstitial fluid
How do you calculate Net Filtration Pressure?
NFP = (BHP+IFOP) - (BCOP+IFHP)
Net Filtration Pressure = Filtration - Re-absorption