respiratory and urinary review

Question 1

Where is the location of the chemoreceptors most sensitive to changes in pH?

Answer 1

medulla, carotid bodies, and aortic bodies

Question 2

Are peripheral chemoreceptors more sensitive to changes in oxygen or carbon dioxide?

Answer 2

O2

Question 3

What force drives the exchange of oxygen and carbon dioxide?

Answer 3

air weighs which creates a pressure gradient between the alveolar air and the capillary

Question 4

Explain what the phrase ‘air weighs’ means, and why it is important for respiration.

Answer 4

atmospheric air has weight

Question 5

What is the barometric pressure of dry atmospheric air at sea level?

Answer 5

760mmHg

Question 6

Explain why it is difficult for humans to climb to high elevations?

Answer 6

because the pressure is lower and the pressure gradient is lower.

Question 7

What is Fick’s law, and how does it pertain to gas diffusion?

Answer 7

the rate of transfer of a gas (VGas) through a sheet of tissue is proportional to the tissue area (A) and the difference in partial pressure between the two sides (p1-p2) and inversely proportional to the tissue thickness (T)
Vgas= A/T x D (P1-P2)

Question 8

What would happen to diffusion of oxygen if the alveolar wall thickened?

Answer 8

It would reduce the rate of diffusion

Question 9

What happens to diffusion of oxygen if the partial pressure is dropping in the atmospheric air?

Answer 9

the rate of diffusion would decrease

Question 10

What are the two methods that oxygen is carried in the blood?

Answer 10

dissolved oxygen follows Henry’s law such that the amount dissolved is proportional to its partial pressure
the second method is through the blood bound to hemoglobins on RBC

Question 11

How many oxygen molecules can bind to one hemoglobin molecule?

Answer 11

4

Question 12

What happens when 1 oxygen molecule binds to hemoglobin?

Answer 12

it alters the structure of hemoglobin to make it easier for other oxygen molecules to bind

Question 13

What is SaO2?

Answer 13

oxygen saturation

Question 14

What is O2 capacity? Can SaO2 be near maximum but still have inadequate oxygen delivery? Explain.

Answer 14

97.5%. Yes because there is no guarantee that the blood is well-oxygenated.

Question 15

What is a normal blood concentration for Hb?

Answer 15

75%

Question 16

What is a normal O2 capacity?

Answer 16

95-100%

Question 17

How does the Q for the pulmonary circulation compare to the systemic circulation?

Answer 17

the volume of blood passing through the lungs per minute
systemic is the whole body so Q is much larger

Question 18

What is VO2? What variables do we use to measure it?

Answer 18

oxygen consumption,Qx arterial O2 - Venous oxygen

Question 19

What methods can gases be transported through the blood?

Answer 19

dissolved, as bicarbonate and, combined with proteins as a carbonic compound

Question 20

How much oxygen can be dissolved in the blood?

Answer 20

20.1mL

Question 21

Does the amount of oxygen dissolved in the blood meet the metabolic demands of the body?

Answer 21

through oxidative phosphorylation in mitochondria. this generates ATP. Without ATP there is a loss of resting membrane potential and loss to maintain cardiac functions

Question 22

What are the functions of the urinary system?

Answer 22

to eliminate metabolic wastes and homeostatic ally regulate the water and electrolytes composition of the body fluids

Question 23

What is urea? What are some situations where you might have an excess of urea in the blood?

Answer 23

a byproduct of amino acid catabolism. Kidney disfunction

Question 24

What systems of the body are involved in waste removal?

Answer 24

Kidneys, ureters, urinary bladder, and urthra

Question 25

How much of resting cardiac output supplies the kidney?

Answer 25

20-25%

Question 26

Why do we have such high blood flow to one organ?

Answer 26

because the kidneys filter the blood

Question 27

What are the differences between the glomerular capillaries and other systemic capillaries?

Answer 27

It is highly regulated

Question 28

What is oncotic pressure? What is its effect on glomerular filtration?

Answer 28

pulling pressure. It increases it

Question 29

What does GFR mean?

Answer 29

glomerular filtration rate

Question 30

What is a normal GFR?

Answer 30

125mL/min

Question 31

How much of GFR is reabsorbed?

Answer 31

99%

Question 32

What is autoregulation?

Answer 32

the ability of the nephrons to adjust their own blood and FFR without external control

Question 33

What is the effect of sympathetic stimulation of filtration?

Answer 33

constriction of the afferent arteriole would decrease GFR and urine production

Question 34

Where is renin produced? What is its action?

Answer 34

the kidney causes vasoconstriction and water conservation, including decreasing filtration stimulating aldosterone secretion, and increasing water and electrolyte reabsorption.

Question 35

Where is angiotensin converting enzyme produced?

Answer 35

the liver

Question 36

What are the effects of angiotensin II on blood pressure and blood volume?

Answer 36

blocks high blood pressure

Question 37

Which section of the nephron is the primary site of reabsorption?

Answer 37

proximal convolution tubule

Question 38

What would be the effect of inadequate ATP on removal of sodium from the filtrate?

Answer 38

there would be no energy for reabsorption

Question 39

What provides the energy for most reabsorption?

Answer 39

active transport

Question 40

What % of filtrate is reabsorbed in the PCT?

Answer 40

85%

Question 41

What is absorbed in the descending loop of Henle?

Answer 41

water and sodium chloride

Question 42

What is absorbed in the ascending loop of Henle?

Answer 42

sodium chloride

Question 43

How does the osmolarity of the filtrate compare between the PCT and the loop of Henle?

Answer 43

the loop of henle increasing the filtrate

Question 44

What substances are secreted into the nephron?

Answer 44

urea, ureic acid ammonia, catecholamines, prostaglandins, pollutants, drugs

Question 45

How are substances transported into the nephron, actively or passively?

Answer 45

actively

Question 46

What substances are secreted into the nephron to regulate acid-base balance?

Answer 46

H and HCO3

Question 47

Where is aldosterone secreted from?

Answer 47

adrenal cortex

Question 48

What stimulates aldosterone secretion? Does aldosterone directly increase water reabsorption?

Answer 48

decreased sodium I the blood, decreased blood pressure and angiotensin production. Yes it does

Question 49

Where is ADH secreted from?

Answer 49

posterior lobe the pituitary gland due to increased blood osmolarity and dehydration

Question 50

What are the actions of ADH on the nephron? What type of channels are made in response to ADH?

Answer 50

makes the duct more permeable to water and allows filtrate to diffuse. Makes aquaporins

Question 51

What would be the effect of increased urine volume on blood volume?

Answer 51

blood volume would decrease

Question 52

What is the role of the nephron in water retention?

Answer 52

allows smalls molecules and wastes like water pass through

Question 53

What is the countercurrent multiplier?

Answer 53

the salinity gradient in the medulla

Question 54

What is the difference in osmolarity between the cortex and the medulla, and what role does this play in water retention?

Answer 54

lower in the medulla than the cortex. This makes the medulla more permeable to water

Question 55

What would happen to the retention of water with a low osmolarity in the filtrate?

Answer 55

the water retention would increase