exam 1 (practice questions)

Question 1

Fludrocortisone is a steroid hormone used to treat disease. Which of the following most likely occurs when it encounters a target cell?

Answer 1

it diffuses through the cell membrane and binds to receptors in the cytoplasm or nucleus

Question 2

what are exocrine glands

Answer 2

glands that secrete substances like sweat, mucus, saliva, enzymes

Question 3

what are antagonistic functions and what purpose do they serve

Answer 3

antagonistic functions: actions or processes in the body that have opposite directions or opposing effects

• ex. muscle contracts and antagonist muscle relaxes

purpose: homeostasis!!

Question 4

prolactin and what releases it

Answer 4

prolactin stimulates lactation in women after childbirth and it is released by the pituitary gland

Question 5

difference between anterior pituitary gland and posterior pituitary gland

Answer 5

anterior pituitary gland makes and releases hormones directly, while posterior pituitary gland stores and releases hormones that are made elsewhere in the brain

Question 6

secretin

Answer 6

regulates digestion in the body
- released by S cells
- in the small intestine

Question 7

explain liver cells converting glycogen into glucose during the fight or flight response

Answer 7

glycogen = stored form of glucose

liver breaks it down when adrenaline is high so that it goes straight into bloodstream = glucose fuels muscle and brain cells

Question 8

explain the answer to this question: which occurs under stressful conditions that include shock, low blood pressure, and low blood sugar levels?

Answer 8

ACTH stimulates release of corticosteroids

• ACTH - produced by pituitary gland
• body releases ACTH when faced with stress or needs to respond to a challenge
• corticosteroids: think cortisol, respond to stress, help body adapt to stress by increasing energy levels, regulate metabolism and immune response

Question 9

parathyroid hormone (PTH)

Answer 9

• works to increase blood calcium levels
• acts on various target organs, including bones, kidneys (prevents calcium from leaving as urine), and intestines (promotes calcium absorption)

Question 10

calcitonin

Answer 10

• produced by C cells of the thyroid gland
• brings down blood calcium levels when they get too high

Question 11

epinephrine and norepinephrine

Answer 11

released in response to fight or flight

• epinephrine is also called adrenaline

Question 12

example of antagonistic hormones that regulate homeostasis

Answer 12

insulin and glucagon regulating blood glucose levels

Question 13

a new hormone is discovered that appears to play a role in bone development. the hormone is hydrophilic and composed of several amino acids. how should this hormone be classified?

Answer 13

as a peptide hormone

• peptide hormones are hydrophilic bc they do not cross the cell membrane, several amino acids also means its big in size

Question 14

TSH

Answer 14

thyroid stimulating hormone - regulates activity of the thyroid gland (located in the neck)

• TSH levels rise to stimulate thyroid gland to produce more hormones when thyroid hormones are low

Question 15

a patient with a thyroid tumor has their thyroid gland removed. without a thyroid gland and without synthyroid, what will most likely occur to her blood TSH levels and metabolic rate or energy levels?

Answer 15

TSH levels will be abnormally high and metabolic rate will be low

Question 16

a patient exhibits symptoms of gigantism and rapid growth. what endocrine gland is likely affected in this individual?

Answer 16

anterior pituitary (responsible for producing and releasing growth hormone)

Question 17

a researcher is studying the function of a peptide hormone in rabbits and humans. he notices that this hormone has a different effect in these 2 mammals, even though the hormone receptor has the same sequence and structure in both animals. what accounts for this difference in hormone function?

Answer 17

sequence differences in the components of the associated signal transduction pathway (differences caused by different physiological responses to the hormone)

Question 18

the decreased solute concentration of the filtrate after passing through bowman’s capsule is caused by

Answer 18

active transport of NaCl out of the proximal convoluted tubule

Question 19

what would happen if you placed a trout (freshwater fish) into a saltwater tank at the aquarium and made some observations?

Answer 19

the fish would lose water

Question 20

what do all excretory organs have in common?

Answer 20

a filtration system that filters nitrogenous waste from the body fluids

Question 21

Antidiuretic hormone (ADH) controls how diluted or concentrated urine is by controlling the permeability of the ________

Answer 21

collecting ducts to water

Question 22

3 forms of nitrogenous waste in order from least to most toxic

Answer 22

uric acid → urea → ammonia

Question 23

circulatory systems help to overcome which of the following physiological challenges?

Answer 23

the slow rate at which diffusion occurs over large distances

Question 24

a decrease of blood pH from 7.4 to 7.2 would cause hemoglobin to _______

Answer 24

bind to fewer oxygen molecules (increasing the pH would also increase affinity for oxygen molecules)

Question 25

what directly happens to the carbon dioxide produced by humans?

Answer 25

it is converted to bicarbonate ions

• this is because bicarbonate ions flow more effectively through the body as they go to the lungs to be eliminated
• also they help maintain the pH of blood and other bodily fluids

Question 26

which describes how an organism senses a disturbance in gas levels?

Answer 26

the medulla oblongata, which is in contact with the cerebrospinal fluid, monitors pH and uses this measure to control breathing

Question 27

which statement correctly compares respiration in fish and mammals?

Answer 27

the movement of respiratory medium in mammals is bidirectional (gas exchange goes both ways through the same pipe) but in fish it is unidirectional (flows over the gills in one direction)

Question 28

what would the impact of a nonfunctional thrombin protein be on an organism?

Answer 28

the organism’s blood would not clot effectively

Question 29

the velocity of blood flow is lowest in capillaries because _______

Answer 29

the total cross sectional area is greater in the capillaries than in any other part of the circulatory system

Question 30

damage to the SA node in humans is most likely to result in a ___________

Answer 30

disruption on the rate and timing of cardiac muscle contractions

Question 31

why is there an elastic layer found in arteries but not found in veins?

Answer 31

blood pressure is higher in arteries than veins, and the elastic layer helps maintain the structure of the artery

Question 32

which of the types of blood vessels would have the greatest resistance to flow?

Answer 32

capillaries

Question 33

why are birds able to extract more oxygen than mammals from an equal volume of air?

Answer 33

birds do not have air mixing in their lungs; air flows in a unidirectional manner across the lung surface for increased diffusion

• they have air sacs too that help ventilate the respiratory systems

Question 34

much of the fluid that moves across capillary walls and into the tissues moves as a result of filtration, forced by blood pressure. O2 on the other hand, travels from the capillaries into the tissues because:

Answer 34

of a concentration gradient between O2 in the tissues and O2 in the blood

Question 35

what happens to the production of insulin and glucagon in a healthy person after eating a carbohydrate-rich meal?

Answer 35

insulin levels increase and glucagon levels increase

(tbh it says that glucagon levels decrease but im not sure what is right, directly after both should increase)

Question 36

how does the absorption of fat differ from that of carbohydrates?

Answer 36

most absorbed fat first enters the lymphatic system, whereas carbohydrates directly enter the blood

Question 37

over the counter medications for acid reflux or heartburn block the production of stomach acid. which of the following cells are directly affected by this medication?

Answer 37

parietal cells

Question 38

what process is used to break down fats into fatty acids and glycerol and protein into amino acids?

Answer 38

hydrolysis (water molecules when breaking bonds)

Question 39

name 2 chemicals or enzymes secreted by the stomach when an organism is eating

Answer 39

HCl, pepsin, gastrin

Question 40

why do vegetarians have to watch their diets and eat foods in combination

Answer 40

because eating meat provides all 8 essential amino acids and because vegetarians dont eat meat, they have to combine foods in a way that provides those essential amino acids

Question 41

measuring which of the following amounts would most accurately determine the metabolic rate of an animal?

Answer 41

the energy used by an animal in a given time

Question 42

which characteristic of small mammals created the selective pressure that favored the use of brown fat to generate metabolic heat?

Answer 42

small mammals have a large surface area to volume ration, which allows rapid heat loss

Question 43

the panting responses observed in overheated birds and mammals dissipate heat loss by what process?

Answer 43

evaporation

Question 44

in a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm _________

Answer 44

invests little energy in temperature regulation

Question 45

individuals with type 2 diabetes produce insulin, but target cells do not respond to insulin by taking in sugar. which component of the feedback system is broken in these individuals?

Answer 45

the response

Question 46

which characteristic is most likely for an epithelium that is specialized for passive diffusion of materials from one fluid filled compartment to another?

Answer 46

a single layer of flattened cells