Midterm Flashcards
The following changes occur when an individual moves from a supine position to a standing position:
A. Decreased venous return
B. Decreased cardiac output
C. Venous blood pooling in the lower extremities
D. Compensatory increase in sympathetic outflow
E. All of the above
E. All of the above
- When a person stands, blood pools in the lower extremities–>venous return decreases–>stroke volume and cardiac output decreases–>arterial pressure decreases–>activation of baroreceptor reflex–>increased sympathetic outflow to the heart and blood vessels.
Which of the following statements regarding lung zones is CORRECT?
A. The base is less ventilated
B. The apex is better perfused
C. The V/Q ratio is higher at the base
D. The V/Q ratio is lower at the apex
E. The apex has the highest regional arterial PO2
E. The apex has the highest regional arterial PO2
- At the apex (higher V/Q), regional arterial PO2 is highest and regional arterial PCO2 is lowest because gas exchange is more efficient.
- Perfusion is lowest at the apex and highest at the base because of gravitational effects on arterial pressure.
- Ventilation is lower at the apex and higher at the base because of gravitational effects in the upright lung.
Constriction of the afferent arteriole will have the following effect:
A. Increased GFR
B. Increased renal plasma flow
C. No change in filtration fraction
D. Increased glomerular hydrostatic pressure
E. All of the above
C. No change in filtration fraction
- Constriction of the afferent arteriole (e.g. sympathetic) decreases RPF and decreases GFR by decreasing the glomerular hydrostatic pressure.
- There is no change in the filtration fraction.
Resection of the terminal ileum would MOST LIKELY result in which of the following?
A. Decreased carbohydrate absorption
B. Increased iron absorption
C. Increased bile acid enterohepatic circulation
D. Steatorrhea
E. Decreased water content of feces
D. Steatorrhea
- Ileum of the small intestine is responsible for enterohepatic recirculation of bile acids which are needed for absorption of fats.
- Resection of the terminal ileum would cause steatorrhea and diarrhea.
- Iron is absorbed in the duodenum.
- Most of the carbohydrates are absorbed before it reaches the terminal ileum.
TRUE for isometric contractions:
A. Length-tension relationship can be measured
B. Measured when load is held constant
C. Load against which the muscle contracts is fixed
D. Force-velocity relationship can be measured
E. All of the above
A. Length-tension relationship can be measured
- Length-tension relationship measures tension developed during isometric contractions when the muscle is set to fixed lengths.
- Force velocity relationship measures the velocity of shortening of isotonic contractions when the muscle is challenged with different afterloads.
TRUE for the olfactory pathway?
A. Receptor cells are located in the olfactory bulb
B. Output from mitral cells projects to the prepiriform cortex
C. Mitral cells are third-order neurons in the olfactory bulb
D. The olfactory tract pass through the cribriform pate on their way to the olfactory bulb
E. All of the above
B. Output from mitral cells projects to the prepiriform cortex
- SIMILAR TO PREVIOUS BOARD EXAM CONCEPT/PRINCIPLE: Receptor cells are located in the olfactory epithelium. CN I (olfactory nerve) pass through the cribriform plate and carries information from the olfactory receptor cells to the olfactory bulb. Mitral cells are second-order neurons that sends its output thru the olfactory tract to the prepiriform cortex
The following are actions of thyroid hormone, EXCEPT:
A. Maturation of the CNS in the perinatal period
B. Stimulate bone maturation
C. Up-regulates β1-adrenergic receptors in the heart
D. Increases the synthesis of Na+-K+-ATPase pump
E. Increased glycogenesis
E. Increased glycogenesis
- Thyroid hormones act synergistically with growth hormone and somatomedins to promote bone formation and maturation.
- Maturation of the CNS requires thyroid hormone in the perinatal period.
- Thyroid hormone has many of the same actions as the sympathetic nervous system because it upregulates B1-adrenergic receptors in the heart. It increases the synthesis of Na-K-ATPase and consequently increases O2 consumption.
- Overall, metabolism is increased to meet the demand for substrate associated with increased O2 consumption
An adolescent female complains of weakness, orthostatic hypotension and increased skin pigmentation. If Addison disease is considered, the following effects are expected, EXCEPT: A. Decreased Na reabsorption B. Decreased K secretion C. Decreased H secretion D. Increased water reabsorption E. Increased serum osmolarity
E. Increased serum osmolarity
- Addison disease is adrenocortical insufficiency due to the destruction or dysfunction of the entire adrenal cortex. The lack of mineralocorticoid function has the following effects on the kidney: decreased Na reabsorption, decreased K secretion, and decreased H secretion.
- As a result, there is ECF volume contraction, hyperkalemia, and metabolic acidosis. The ECF volume contraction also stimulates ADH secretion causing increased water reabsorption which results in hyponatremia and decreased serum osmolarity.
TRUE for the vomiting center:
A. It is located in the fourth ventricle
B. It is activated by emetics, radiation, and vestibular stimulation
C. It can be stimulated by tickling the back of the throat
D. Stimulation results in a wave of reverse peristalsis, moving the GI contents in the caudad direction
E. All of the above
C. It can be stimulated by tickling the back of the throat
- Vomiting is a wave of reverse peristalsis that moves the GI contents in the orad direction. The vomiting center in the medulla is stimulated by tickling the back of the throat, gastric distention, and vestibular stimulation (motion sickness).
- The chemoreceptor trigger zone in the 4th ventricle is activated by emetics, radiation, and vestibular stimulation
The QRS complex coincides with which phase of the cardiac cycle: A. Atrial contraction B. Isovolumic contraction C. Isovolumic relaxation D. Rapid ventricular ejection E. Rapid ventricular filling
B. Isovolumic contraction
- P wave - coincides with atrial contraction;
- QRS complex - coincides with isovolumic contraction;
- T wave - coincides with slow ventricular relaxation.
The isoelectric segment of the ECG that represents the period when the ventricles are depolarized: A. QT interval B. T wave C. QRS complex D. ST segment E. PR interval
D. ST segment
SIMILAR TO PREVIOUS BOARD EXAM CONCEPT/PRINCIPLE:
* ST segment is an isoelectric segment from the end of the S wave to the beginning of the T wave. It represents the period when the ventricles are depolarized.
Compute for the expiratory reserve volume if the tidal volume is 0.5 L, inspiratory reserve volume is 3 L, vital capacity is 4.7 L, and total lung capacity is 5.9 L: A. 1100 ml B. 1.4 ml C. 1400 ml D. 1200 ml E. 1.2 ml
D. 1200 ml
SIMILAR TO PREVIOUS BOARD EXAM CONCEPT/PRINCIPLE:
Since VC = IRV + TV + ERV, simply add IRV and TV (0.5 L + 3 L = 3.5 L) then subtract it to VC to get the ERV (4.7 L - 3.5 L = 1.2 L)
The segment of the nephron that is impermeable to H2O:
A. Thin descending limb of loop of Henle
B. Thick assending limb of loop of Henle
C. Collecting ducts
D. PCT
E. Late DCT
B. Thick assending limb of loop of Henle
- Thick ascending limb of the loop of Henle is impermeable to water. This segment is called the diluting segment because it NaCl is reabsorbed without water.
TRUE for the hypothalamic set point for body temperature:
A. Temperature sensors on the body relay information to the posterior hypothalamus
B. If the core temperature is below the set point, mechanisms for heat loss are activated
C. If the core temperature is above the set point, heat-generating mechanisms are activated
D. The posterior hypothalamus is responsible for shivering
E. Pyrogens decrease the set-point temperature
D. The posterior hypothalamus is responsible for shivering
Temperature sensors on the skin and in the hypothalamus “read” the core temperature and relay this information to the anterior hypothalamus.
- If the core temperature is below the set point, heat generating mechanisms (e.g. increased metabolism, shivering, vasoconstriciton of cutaneous blood vessels) are activated by the posterior hypothalamus.
- If the core temperature is above the set point, mechanisms for heat loss are activated by the anterior hypothalamus. Pyrogens increase the set point temperature.
The hormone responsible for contraction of gallbladder and relaxation of sphincter of Oddi is secreted from which cells? A. G cells B. I cells C. S cells D. M cells E. K cells
B. I cells
- CCK is released from the I cells of the duodenum and jejunum. It stimulates contraction of the gallbladder and simultaneously causes relaxation of the sphincter of Oddi for secretion of bile.
G cells–>Gastrin; S cells–>Secretin; K cells–>GIP; M cells–>Motilin;
