Bio: Endocrine, Cardiovascular, Lymphatic, and Immune System

Question 1

Endocrine glands:
product, location of product, ducts?

Exocrine products, location of products, ducts?

Answer 1

Endocrine glands -> hormones, location in blood, no ducts

Exocrine glands -> products = saliva, sweat, bile, tears, location of products = inside a cavity that is different from their target location, there are ducts

Question 2

Peptide vs steroid hormones: 
Made from
location of receptor
mxn of action 
speed of effects
longevity of effects 
When synthesized? 

What looks like peptide but acts like a hormone?

Answer 2

Peptides: made from aa, receptor on the cell surface, mxn of action = second messenger, fast, longevity = temporary
Synthesized in advance and stored

Hormones:
Made from -> cholesterol
location of receptor -> intracellular receptor
mxn of action -> bind DNA and modify transcription
speed of effects -> slower
longevity of effects -> longer lasting
Synthesized as needed

Thyroid horm is derived from aa, looks like peptide but does not act like peptide, hydrophobic and acts like steroid, bind intracell and interact with DNA

Question 3

3 mxn to control hormone release?

Answer 3

Neural: an action potential causes release of hormone
ex. sympathetic nervous system (acetylcholine) trigger release epinephrine

Hormonal: hormones that control the release of other hormones: tropic hormones ex. ACTH, release hormones from the adrenal cortex

Humoral: something in blood, not itself a hormone, trigger release of a hormone
ex. glucose can control insulin and glucagon

Question 4

“Adeno”

Adenohypophysis

Answer 4

anterior pituitary

Question 5

What does the anterior pituitary secrete?

Answer 5

FLAT PIG

FSH
LH
ACTH
TSH

Prolactin
i ignore
Growth hormone

controlled hormonally by the hypothalamus

Question 6

What does posterior pituitary secrete? What is it made of? How it is controlled?

Answer 6

STORES and releases two hypothalamic hormones: Vasopressin/ADH and oxytocin
controlled neurally by hypothalamus

Question 7

Anteriograde

Portal veins?

Answer 7

soma to terminal down axons

Portal veins transport factors from hypothalamus to capillaries in anterior pituitary where there are hormone making cells

Question 8

What kind of cells end in posterior pituitary? What do they do?

How does with work with prolactin

How does neg feedback work with hormones in this region?

Answer 8

Neuroendocrine cells
Neurons make hormones and transport them down their axon and release them via action potential to capillaries in posterior pituitary

Hypothalamus releases growth hormone releasing hormones (there are specific ones for certain hormones, but to release prolactin you stop its inhibition factor so that its released) to trigger anterior pituitary

Need dual neg feedback for BOTH anterior pituitary and hypothalamus

Question 9

Compare/contrast veins and arteries

pressure:
blood moves by:
muscular walls:
elastic:

Answer 9

VEINS
pressure: low 
blood moves by: anything that squishes the vessel (normal muscle movement) and valves 
muscular walls: no
elastic: no

ARTERIES
pressure: high
blood moves by: pressure gradient (forward momentum)
muscular walls: yes
elastic: yes -> Arteries are elastic -> means they can recoil, stretch and then go back to OG shape

Question 10

Describe the movement of fluid in/out of the following path:
arteriole -> capillary -> venule

What is hydrostatic pressure? Oncotic pressure?

Answer 10

Hydrostatic pressure -> pressure exerted by a fluid

Oncotic pressure -> Pressure exerted by a proteins or particles

Arteriole -> high pressure, hydrostatic pressure high and fluid leaks out capillary so less and less fluid in there by time get to venule, feel presence of proteins in capillary more (bc loss of fluid, lower hydrostatic pressure and higher concentration of particles) so since more proteins, more fluid will want to enter the capillary now where particles are, direction of fluid changes throughout the path of the capillary so fluid flows back in due to osmosis

originally fluid fly out of capillary due to hydrostatic pressure of water wanting to go out and by end of capillary, fluid wants to fly in bc of oncotic pressure (double check if due to oncotic pressure, but I’m pretty sure correct)

Question 11

Is the movement of fluid equal on both sides?

What do lymphatic vessel do? What are lymph nodes/what do you find in them?

Answer 11

You lose some fluid in process, more going out than comes back in
Once it leaks out it starts flowing away from site -> lymphatic system picks up fluid, recollect lost water and put that back into blood

Lymphatic system: structurally and functionally like veins
Lymph vessels also have valves and best movement when have muscle contraction and puts fluid back into circulatory system, but could be bad if virus or bacteria then transported back into bloodstream but to protect against this we have concentrated pockets of WBC = lymph nodes which are ready for foreign invaders which are hanging out in fluid

Question 12

Name valves/arteries/veins of heart and imagine their location

Answer 12

(left of diagram, right side of heart) Blood comes from body into superior vena cava, right atrium, tricuspid AV valve, right ventricle, pulmonary semilunar valve, pulmonary artery, to lungs, to pulmonary veins, left atrium, bicuspic (mitral) valve, left ventricle, aortic valve, aorta, to body

You always “try” before you “buy” tricuspid before bicuspid

Question 13

*Assume ventricular when talk about systole and diastole unless they say atrial
Ventricles have bigger job than artriole

What is systole and diastole?
What does 1st sound “lub” represent? 2nd sound “dub”?

What is the normal blood pressure? Is 130/98 okay?

Answer 13

“Sis got a music contract” -> close AV valve before systole contraction

There’s a left and right AV valve
left and right semilunar valves

Systole -> heart contraction
Diastole -> heart relaxation

1st sound “lub”:
Close AV valves
Begin systole

2nd sound “dub”
Close semilunar valves
Begin Diastole

systolic/diastolic
pressure in arteries when heart contracted/ Pressure in arteries when heart relaxed
120/80

High diastolic pressure is concerning bc supposed to be relaxed ventricles

Question 14

Equation for cardiac output?
What three things can affect stroke volume?

What happens if lost blood? Eat salt? What can happen if suddenly halt after intense exercise?

Frank Starling: The greater the venus return the greater the cardiac output, what are two principal ways to increase venus return?

Answer 14

cardiac output (vol pumped per min) = stroke volume (vol pumped per beat) * heart rate (beats per min)

more blood in, more blood out

stroke volume changed by change in blood volume, change in activity level (bc of veins), change in posture (has to do with gravity, ex if pass out, good to elevate legs to get more blood to heart and then brain)

If lost blood bc bleed then stroke volume decrease
If eat a lot of salt, ramen, etc and salt goes into blood stream, and drag water with it so more water go into blood which increase stroke volume

Explanation for changing your activity level -> When running-> great blood flow through vein bc moving and heart pumping out effectively
If come to sudden halt -> blood through venus end poor bc not moving but your heart does not catch up that fast and still beating fast so pass little squirts of blood out, cambers not filled, aorta not full so can’t bring blood to brain, etc, this drop in blood pressure could be so severe that could die -> Less blood coming into heart means less blood coming into heart

Can increase venus return by: increasing total volume of blood in the circulatory system 2) contraction of large veins can propel blood toward heart

Question 15

What is peripheral resistance? How does it relate to pressure?

Answer 15

Peripheral resistance -> how hard it is to move blood through vessels
Vasoconstriction (vessels constricted) , decrease diameter, decrease flow, increase resistance, increase blood pressure

Vasodilation (vessels dilated): increase diameter, increase flow, decrease resistance, decrease blood pressure

Question 16

Cardiac muscle cell action potential:

What is the resting potential ? What is different about cardiac muscle cell action potential? How are cardiac muscle cells stimulated?

How does absolute refractory period of cardiac muscle cell relate to that of skeletal muscle and neuron?

Answer 16

RMP = -80 (cardiac muscle cells different than skeletal muscle bc diff proportions of channels open)

Graph has a plato
Stimulated by pacemaker cells through gap junctions (found in intercalated disks, the connections between cardiac muscle cells, and this is ex. of electrical synapse) -> automatically stim and reach threshold and then open voltage gated Na channels and mem potential becomes more pos
Difference -> reach plato have additional voltage gated Ca2+ channel (when open, they stay open longer than the fast sodium channels do causing the membrane depolarization to last longer in cardiac muscle cells than in neurons and producing a plateau), eventually it closed by autoinhibitory signal after certain amount of ions go through, now only voltage gated K channel is working and cell returns to -80mV resting potential

Absolute refractory period of cardiac muscle cell is longer than that of skeletal muscle and neuron

Question 17

Cardiac muscles can have what kind of contraction (why unique/different than skeletal muscle)?
What unique channel do cardiac muscles have?

Answer 17

Extended the absolute refractory period bc of tetanic contractions
Caridac muscle -> 100 times longer action potential!! Cannot fire action potential fast enough to get tetanic contraction bc long absolute refractory period
Cardiac Autorhythmic cells
-> unique mxn don’t have normal Na/K pump, leak channels, bc don’t stay at rest

KNOW -> they have a unique channel called funny channel which is Na+ leak channel (Dont understand in depth but KNOW reason for auto rhythmic bc of Na Leak channel that allows it to go to higher and higher values, never stops!)
Skeletal muscle cells and other myocytes depolarize because of a Na+ influx, not Ca2+ like the SA node. This Ca2+ influx drives the membrane potential of the SA nodal cells toward the positive Ca2+ equilibrium potential

-> (UNIQUE, Na leak in whenever to make it more pos and membrane can reach threshold! And open a SLOW voltage gated Ca2+ channel! And unique voltage gated K channels at peak in diagram and open at +20 and K leaves cell and K channel close and don’t hit rest bc have Na leak channels which allow us to continuously have potential go to higher and higher, heart beats continuously bc of these autorythmic cells and they communicate with cardiac muscle cells

Skeletal muscle can have tetanic contraction -> (looks like mini steps building up onto of each other) multiple action potentials to build up to max state, faster action potential

Question 18

What controls cardiac muscle cells?

What are the two types of nodes?

Answer 18

Gap junctions at specific points b/w pacemaker cells and cardiac muscle cells -> at SA node and purkinjie fibers

All pacemaker cells have gap juncitons with eachother and only at purple spots (in diagram) can action potential go from pacemaker cell to cardiac muscle cell -> order in which things contract
Gap in purple is gap b/w pacemaker and cardiac muscle cells
Green is direction of impulse
SA -> contract in right atrium and goes to left atrium through pace maker cells and then cardiac muscle cells in left atrium, then takes lil more time for impulse to travel down to ventricle and pass impulse from pacemaker to cardiac

SA node comes before AV nodes

Question 19

Atrial muscle cells and ventricular muscle cells are/are not electrically connected by gap junctions

AV node delays impulse, allowing ___contract first, before ______

Impulse travels to the bottom of the heart before entering ventricular muscle, allowing ventricles to contract from ____ to the _____

Answer 19

Atrial muscle cells and ventricular muscle cells are NOT electrically connected by gap junctions

AV node delays impulse, allowing atria contract first, before ventricles

Impulse travels to the bottom of the heart before entering ventricular muscle, allowing ventricles to contract from BOTTOM to the TOP

Question 20

How do steroids travel?

What are the components of blood (3)?

Answer 20

Blood is polar (electrolyes, etc) so if want to travel need to be polar -> so steroids have carrier protein

Blood is made of plasma, leukocytes (WBC) and platelets, and hematocrit (RBCs)

Question 21

Write out the CO2 equilibrium reaction and what is present in lungs versus tissues

What is oxygen and CO2 most bound to?

Answer 21

CO2 + H20 -> sigmoidal curve
At Lungs, there is a lot of HCO3- so shift rxn to left so turns HCO3- into CO2 (carbon dioxide waste turned into CO2 so can get rid of CO2 in lungs)
In tissues as CO2 builds up this shift rxn to right and turn into HCO3- a form that can travel better in blood so can go to lungs

Question 22

What is the innate immune system? There are physical barriers, chemicals, and cells
Name some of these, including cell types associated with this

What is the complement pathway?

Answer 22

broad/non-specific defense
Barriers: skin, eyelashes (hair)

Chemicals: mucus, tears, saliva, (lysozyme), stomach pH

Cell types:
*MACROPHAGES

Neutrophils kill bacteria, first there when get wound fight off initial infection

Basophil stim inflammation

Eosinophils parasitic infection

NK cells

Complement pathway (not a cell) -> set of proteins to make chain rxn to lyse bacteria, complex that pokes holes in bacteria

Question 23

What happens when naive b cell encounters pathogen for first and second time?

What happens in general when encounter Ag first and second time?

Answer 23

If naive b cell actually binds Ag that matches it is stimulated mature and makes a memory cell which is just like naive b cell and hold instruction of how to make that Ab again if needed in future, and makes plasma cells which shoot out Ab a rapid speed
Ab mark for destruction but do not kill themselves

When encounter Ag in general:
1st exposure (7 to 10 days for primary immune response) then get Ab, active T cells, memory cells
2nd exposure (less than 1 day for second immune response) get Ab, active T cells, more memory cells

Question 24

B cells = “humoral” immunity
What do they do?
How do we have a B cell with Abs to everything even before we ever encountered it?

Answer 24

secrete Abs in blood/lymph
Each B cell makes only one type of Ab, so we need a lot of B cells
once naive B cell is stimulated it can form memory b cells which carries info of how to make this Ab in the future and plasma cells which secrete a lot of Abs

B cells can undergo VDJ recombination with their segment of DNA that codes for Ab

Question 25

On what types of cells are MHC I and II found?
Name 2 types of T cells you should know (they each have 2 names):

MHC I:

a) found on ________
b) allows cells to display_____ on cell surface

MHC II

a) found on macrophages and B cells
b) allows cells to display eaten material on cell surface

Answer 25

All cell body types, except RBC have MHC I (presents what cell has inside and T cell asks what’s inside)
MHC II found on macrophages and B cells so show any eaten material, HIGHER CHANCE OF COMING ACROSS INFECTION FIRST bc specifically shows material that has been phagocytosed

Helpful to remember -> MHC has to multiply to 8 ex. CD4 -> 4 * 2(from MHC II) =8

Killer T cell has 2 receptors -> one that recognizes self and the contents from within the body cell (could be Ag) and then can induce apoptosis

Killer Ts (CD 8+) -> kill your own abnormal cells, look for Ag on MHC I

Helper Ts -> secrete chemicals (cytokines) that allow B cells and killer T cells to proliferate, look for Ag on MHC II

MHC I:

a) found on all cells (except RBC)
b) allows cells to display cell contents on cell surface

MHC II

a) found on macrophages and B cells
b) allows cells to display eaten material on cell surface

Question 26

Many random B cells and T cells are produced that recognize both self and non-self proteins
So these are all exposed to normal “self” antigens -> where are self-recognizing B cells and recognizing T cells destroyed -> B cells destroyed, etc in ________ and T cells destroyed, etc ____

What can happen when B and T cells recognize self? When recognize non self?

Answer 26

B cells destroyed in Bone marrow and T cells destroyed, etc in thymus

When B and T cells recognize self:
Apoptosis
Anergic (inactive)
Eliminating self-reactive cells so that we don’t get autoimmune diseases
If the anergic cell decides to wake up later in life then get autoimmune later in life

When recognize non self?
Enter general circulation

Question 27

To maximize entry of calcium into cardiac muscle, it has… (structure)

Answer 27

To maximize entry of calcium into cardiac muscle, it has T tubules

Question 28

What is most common Ab type? Other important one?

Answer 28

IgG = involved in on going immune response 
IgM = pentameric in blood but monomeric structure on B cell, involved in initial immune response

Question 29

Equation for pressure gradient in body (blood pressure)

Answer 29

∆P = Q * R

Q -> blood flow (or cardiac output in L/min)
R -> resistance
Principal determinant of resistance is degree of constriction of arteriolar smooth muscle, also known as precapillary sphincters , if they contract, it is more difficult for blood to flow from arteries to capillaries so resistance increases (peripheral resistance)

Question 30

Increased blood pressure makes it more/less difficult for the heart to eject its load of blood, and increased/decreased blood pressure impairs cardiac function when not enough blood is returned to the pumping heart

Answer 30

Increased blood pressure makes it more difficult for the heart to eject its load of blood, and decreased blood pressure impairs cardiac function when not enough blood is returned to the pumping heart

Question 31

What is the pressure during heart beats? In between heart beats?

Answer 31

Pressure during heart beats -> systolic

In between heart beats -> diastolic