Physiology - exam 1 study guide

In a feedback loop controlling temperature, what compares the status with the set point and determines if its in/out of range?

hypothalamus

What kind of feedback mechanism is thermoregulation?

negative

In thermoregulation, increased body temperature results in what?

• blood vessels dilate

• sweating

In thermoregulation, decrease body temperature results in what?

• constriction of blood vessels

• shivering

What is the toxic byproducts of protein metabolism produced by all animals?

nitrogenous wastes

Nitrogenous wastes form are determined by an animals availability of what to flush?

water

what two animal types can make a hypertonic urine?

birds and mammals

ALL vertebrates can produce a urine that is_____?

isotonic or hypotonic to blood

Nitrogenous wastes are comprised of the breakdown of what two substances?

• proteins

• nucleic acids

What form of nitrogenous waste do most aquatic animals and most bony fish produce?

NH3 / ammonia

What form of nitrogenous waste do mammals, amphibians, sharks and some bony fishes produce?

urea

What form of nitrogenous waste do many reptiles, birds, insects and snails produce?

uric acid

What form of nitrogenous waste is highly toxic, soluble, and requires large volumes of water?

ammonia

What form of nitrogenous waste is moderately toxic, water soluble, and requires a moderate amount of water?

urea

What form of nitrogenous waste is least toxic, highly insoluble, and saves the most amount of water to make?

uric acid

kidneys are thought to have evolved from what animal?

freshwater fish (teleosts)

What kind of fish inhabit a hyperosmotic/hypertonic environment?

freshwater

What kind of fish inhabit a hypoosmotic/hypotonic environment?

saltwater

The vertebrate kidney, in cases of freshwater fish, face the problem of solutes leaving the body, what solution works to combat this?

lots of ATP is used to move salts against concentration gradient and bring ions back into blood

Regarding freshwater fish, in which direction does water flow? are salts gained or lost?

water flows into fish

salts lost

Regarding saltwater fish, in which direction does water flow? are salts gained or lost?

water flows out of fish

salts gained

How do freshwater fish combat their environment?

• rarely drink water

• produce LOTS of dilute urine

• reabsorb ions across nephrons

• actively transport ions across gills into blood

How do saltwater fish combat their environment?

• drink lots of water

• produce small amount of concentrated urine

A starfish’s environment is suddenly deregulated and becomes less salty, causing water to move into its tissues and gain water, is this an example of osmoregulator or osmoconformer?

osmoconformer

A dolphin’s environment is suddenly deregulated and becomes less salty, causing it to use its kidneys to filter out excess water from the surrounding environment is this an example of osmoregulator or osmoconformer?

osmoregulator

Do osmoregulators or osmoconformers use more ATP?

osmoregulators

What is the functioning unit of the kidney?

nephron

steroid hormones are ____ soluble?

lipid

peptide/protein hormones are ____ soluble?

water

amine hormones are ____ soluble?

depends

Where are the receptors in steroid hormones located?

inside cell

Where are the receptors in peptide/protein hormones located?

on cell membrane

testosterone is an example of what hormone class?

steroid

insulin is an example of what hormone class?

peptide/protein

epinephrine is an example of what hormone class?

amino acid

endocrine signaling v paracrine, ect.

goes thru blood stream

How does insulin reach its target? (MORE EXAMPLES LIKE THIS)

flow freely through blood, connects to receptor outside membrane

hormones that bind to a receptor on cell membrane function ____.

quickly

hormones that bind to a receptor inside cell function ____.

slowly

What is the process of epinephrine reaching its target cell?

transported through blood freely, binds to extracellular receptors

What is the process of progesterone reaching its target cell?

transported through blood via carrier protein, binds to intracellular receptors

Where is salt content highest in the kidney?

medulla

What is the driving force behind filtration of blood in the glomerulus?

high blood pressure

overall goal of kidney

process waste products from blood to create urine

During glomerular filtration what is all filtered out of the blood and enters into the filtrate?

everything but blood components

What kind of basic kidney function is selective?

reabsorption

What action occurs in the proximal tubule?

reabsorption

Reabsorption of glucose, amino acids, water and salts occurs in what area of the nephron?

proximal convoluted tubule

In the proximal convoluted tubule, what occurs?

reabsorption of ions, water and nutrients reclaimed from filtrate back into blood

In the nephron, where does bulk reabsorption occur?

proximal convoluted tubule

Which segment of the loop of henle is permeable to water but not NaCl?

descending limb

Where does water passively leave in loop of henle?

thin descending limp

Where does salt actively leave the tubule leave in loop of henle?

thick acsending limb

Which hormones control distal convoluted tubule?

ADH!!

What is released in response to low blood pressure?

ADH

Where is ADH released from?

posterior pituitary gland

How does ADH affect distal convoluted tubule?

aquaporins attach and increase water retention

adh

passive process

What are the stimuli for release of ADH

• high blood sodium

• low bP

• body dehydrated

Which part of the pituitary gland is an extension of the hypothalamus?

posterior pituitary gland

Which two hormones are released by posterior pituitary gland?

• oxytocin

• ADH

What is aldosterone released in response to

low blood sodium

low blood pressure

How does aldosterone act on distal convoluted tubule?

• promotes sodium retention

• increases water reabsorption

ANP is released in response to?

mechanical stretching of atrium, (high bP causes this!)

what raises bP

what lowers bP

gastrin

cck

enterogastric hormones:

secretin, cck, gip

bile salts

emulsify fats

secretin

causes pancreatic secretion of bicarbonate

chyme release into duodenum causes release of?

secretin

what does gip do?

inhibits gastric secretion

when acid enters duodenum…

triggers release of secretin and stimulates bicarbonate release from pancreas

what causes release of chief and parietal cells?

right lung

three lobes

left lung

2 lobes

bronchi → bronchioles → alviole

breathing is a

negative pressure system

we breath in

diaphragm contracts and moves down

we breathe out

diaphragm relaxes and moves up

diaphragmatic breathing!!

During human inhalation, what happens to the diaphragm?

contracts

moves downward

During human exhalation, what happens to the diaphragm?

relaxes

moves upward

What

What kind of secretory cell produces HCl, helping to denature proteins and kill bacteria?

parietal cells

What kind of secretory cell secretes pepsinogen?

chief cells

What causes pepsinogen to turn into pepsin?

secretion of HCl from parietal cells

What digestive enzyme do herbivores lack?

cellulase

Where does nearly all digestion of food take place?

small intestine

Where is increase of surface area most important in digestive system?

small intestine

What accessory organ produces bile?

liver

If a marine bony fish was placed into freshwater what would happen?

In a patient with congestive heart failure, cardiac cells are constantly stretched due to high blood volume. Which hormone will be actively secreted to counteract this condition?

ANP

What would cause ANP to be released?

• high blood vol

• high blood-sodium

• high bP

What hormone would