BIOL385 - TEST 4 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS
P____ determines oxygen-Hb binding.
O2
The ____ the partial pressure of oxygen, the _____ the affinity hemoglobin has for
oxygen.
higher, higher
- oxygen loading onto RBCs in lungs
The ______ the partial pressure of oxygen, the ____ the affinity hemoglobin has
for oxygen.
lower, lower
oxygen unloading at tissues
Any byproduct of metabolism causes a _______ward shift.
right, decreases affinity, oxygen unloads
What factors alveolar ventilation?
airway resistance, rate and depth of breathing, lung compliance
chemical conversion of CO2 to HCO3-
water + CO2 --> HCO3-, via carbonic anhydrase
How is most carbon dioxide transported in the blood?
on RBCs as carbonic acid --> protons and bicarbonate
PO2 in arterial blood
,100 mm Hg
PCO2 in arterial blood
PCO2 = 40 mm Hg
PO2 in venous blood
less than 40 mm Hg
PCO2 in venous blood
greater than 46 mm Hg
Medullary chemoreceptors for ventilation are sensitive to ____.
CO2
Neural networks in the brain stem behave like a ______ _____generator.
central pattern
location of pontine respiratory group
pons
location of dorsal respiratory group
in medulla oblongata
location of ventral respiratory group
medulla oblongata
location of peripheral chemoreceptors, sensitivity
carotid bodies, sensitive to PO2, PCO2, and pH changes, most sensitive to O2 changes
To trigger a reflex in peripheral chemoreceptors, PO2 must fall below __ mm Hg.
60
Describe the release of neurotransmitters from carotid bodies in the event of low
O2.
, low O2 closes potassium channels, cell depolarizes and calcium enters, calcium
entering causes exocytosis of neurotransmitters
location of central chemoreceptors, sensitive
in CNS, changes in PO2 in CSF
Describe the action of central chemoreceptors in respiration.
high PCO2, high bicarbonate from conversion activates central chemoreceptors in CNS,
activates respiratory control centers to increase ventilation
six functions of kidneys
regulation of EC fluid volume and pressure, regulation of osmolarity, maintenance of ion
balance, homeostatic regulation of pH, excretion of wastes, production of hormones
functional unit of the kidney
nephron, millions per kidney
three processes of a nephron
filtration, reabsorption, secretion
Where does filtration happen in the kidney?
renal corpuscle (glomerulus and Bowman's capsule)
Where do reabsorption and secretion occur?
with the peritubular capillaries
reabsorption
from filtrate into blood
secretion
from blood into filtrate
Where does secretion occur?
WITH COMPLETE SOLUTIONS
P____ determines oxygen-Hb binding.
O2
The ____ the partial pressure of oxygen, the _____ the affinity hemoglobin has for
oxygen.
higher, higher
- oxygen loading onto RBCs in lungs
The ______ the partial pressure of oxygen, the ____ the affinity hemoglobin has
for oxygen.
lower, lower
oxygen unloading at tissues
Any byproduct of metabolism causes a _______ward shift.
right, decreases affinity, oxygen unloads
What factors alveolar ventilation?
airway resistance, rate and depth of breathing, lung compliance
chemical conversion of CO2 to HCO3-
water + CO2 --> HCO3-, via carbonic anhydrase
How is most carbon dioxide transported in the blood?
on RBCs as carbonic acid --> protons and bicarbonate
PO2 in arterial blood
,100 mm Hg
PCO2 in arterial blood
PCO2 = 40 mm Hg
PO2 in venous blood
less than 40 mm Hg
PCO2 in venous blood
greater than 46 mm Hg
Medullary chemoreceptors for ventilation are sensitive to ____.
CO2
Neural networks in the brain stem behave like a ______ _____generator.
central pattern
location of pontine respiratory group
pons
location of dorsal respiratory group
in medulla oblongata
location of ventral respiratory group
medulla oblongata
location of peripheral chemoreceptors, sensitivity
carotid bodies, sensitive to PO2, PCO2, and pH changes, most sensitive to O2 changes
To trigger a reflex in peripheral chemoreceptors, PO2 must fall below __ mm Hg.
60
Describe the release of neurotransmitters from carotid bodies in the event of low
O2.
, low O2 closes potassium channels, cell depolarizes and calcium enters, calcium
entering causes exocytosis of neurotransmitters
location of central chemoreceptors, sensitive
in CNS, changes in PO2 in CSF
Describe the action of central chemoreceptors in respiration.
high PCO2, high bicarbonate from conversion activates central chemoreceptors in CNS,
activates respiratory control centers to increase ventilation
six functions of kidneys
regulation of EC fluid volume and pressure, regulation of osmolarity, maintenance of ion
balance, homeostatic regulation of pH, excretion of wastes, production of hormones
functional unit of the kidney
nephron, millions per kidney
three processes of a nephron
filtration, reabsorption, secretion
Where does filtration happen in the kidney?
renal corpuscle (glomerulus and Bowman's capsule)
Where do reabsorption and secretion occur?
with the peritubular capillaries
reabsorption
from filtrate into blood
secretion
from blood into filtrate
Where does secretion occur?
