Pre midterm Flashcards
In a normal heart, what is the average direction of the vector during spread of depolarization through the ventricles? A. -90 degrees B. 120 degrees C. 59 degrees D. 275 degrees E. 90 degrees
C. 59 degrees
- The vector is an arrow that points in the direction of the electrical potential generated by the current flow.
- The left hand side of the patient is the zero degrees. As it moves clockwise it becomes positive. Counterclockwise movement makes it negative.
- The current normally starts at the SA node and flows towards the apex.
- The measured direction is at around +59 degrees.
Part of the vascular system with largest cross sectional diameter. A. Capillaries B. Venules C. Aorta D. IVC E. SVC
Capillaries
Capillaries-2500 cm2
Venules-250 cm2
Aorta 2.5 cm2
Stretching of the RA has a direct effect on the heart's rhythmicity causing it to beat faster. What mechanism is being described? A. Frank starling B. Monroe-kelly C. Bainbridge D. Treppe effect E. Butterky effect
C. Bainbridge
- The stretched right atrium initiates a nervous reflex called the bainbridge reflex passing first to the vasomotor center of the brain and then back to the heart by way of the sympathetic nerves and vagus to increase the heart rate.
A patient has Chronic renal disease due to DM. What could possibly describe the effect of the condition on renal function?
A. Inc glomerular filtration coefficient thus inc GFR
B. Inc glomerular colloid osmotic pressure thus inc GFR
C. Dec glomerular filtration coefficient thus dec GFR
D. Dec glomerular capillary colloid osmotic pressure thus dec GFR
C. Decreased glomerular filtration coefficient thus decreasing GFR.
- Chronic renal disease, DM and hypertension may cause a decrease in filtration coefficient thus decreasing GFR.
Signal that limits respiration in response to lung inflation.
Hering-breuer reflex
Beta 2 receptor stimulation effect.
Bladder wall relaxation
Dorsal column medial lemniscal system conveys what type of stimulus? A. Vibrations B. Pain C. Temperature D. Tickle E. Sexual sensations
A. Vibrations
- pain, temp,tickle and sexual sesnsations enters the anterolateral system on its way to the thalamus
Natural gas is usually odorless, but during gas leak from a pipeline a certain odor can be detected. What substance is responsible for the odor? A. Sulfuric acid B. Camphor C. Oil of wintergreen D. Methylmercaptan E. Indole substances
D. Methylmercaptan
*T his substance (methylmercaptan) has a very low threshold for smell thus even the slightest level of gas leaks, (1/trillionth of a gram/mL of air mercaptan is detectable via smell) it can be detected.
Substance that could act as stimulus for CCK secretion. A. Protein B. Fat C. Bicarbonate D. Insulin E. A and B
E. A and B (Protein and Fat)
- CCK secretion Is stimulated by protein, fat and acid in the Small intestines.
- CCK in turn stimulates panc enzyme secretion, pancreatic bicarbonate secretion, galbladder contraction
The motor impulses from swallowing center to pharynx and upper esophagus that cause swallowing are transmitted successively by the following cranial nerves.
5, 9, 10, 12
- Cranial nerves 5,9,10,12 all participate in the pharyngeal stage of swallowing. Few of the superior cervical nerves also contribute
What peptide hormone function to increase synthesis and release of glucose from the liver and into the body fluids?
A) Glucagon B) Cortisol
C) Aldosterone D) Leptin
E) Insulin
A. Glucagon
- Cortisol is a steroid hormone with anti inflammatory function and regulates metabolism of protein, CHO and fats;
- Aldosterone is also a steroid hormone which increases renal reabsorption of sodium, promotes potassium secretion, and hydrogen secretion;
- Leptin- peptide hormone inhibits appetite, stimulates thermogenesis
- Insulin promotes glucose entry into cells
Hormone that inhibits appetite and stimulate thermogenesis.
Leptin
- Leptin- peptide hormone inhibits appetite, stimulates thermogenesis
If a radius of a blood vessel is doubled, what happens to the rate of blood flood? (Granting all other factors remain constant) A. Unchanged B. Depends upon the pressure C. Doubled D. Quadrupled E. None of the above
E. None of the above
- The flow is increased to 16x normal if the radius is doubled. Pouisille’s law. The rate of the flow of blood is directly proportional to the fourth power of the radius.
Which of the following statements is/are true regarding regulation of respiration?
A. The respiratory center is located bilaterally, solely in the medulla oblongata.
B. The pneumotaxic center primarily functions as the “switch-off” point of the inspiration.
C. A strong pneumotaxic signaling decreases the respiratory rate
D. Hering-breuer reflex refers to cough reflex
E. B and C are correct
B. The pneumotaxic center primarily functions as the “switch-off” point of the inspiration.
*The respiratory center is located in neurons located both in the medulla and pons; A strong pneumotaxic signal increases the RR, the Hering-breuer reflex refers to a signal that limits respiration in response to lung inflation
Which among the following substanes is not freely filtered by the glomerulus? A. Myoglobin B. Sodium C. Glucose D. Inulin E. None of the above
A. Myoglobin
- Glucose, sodium and inulin are among the substances with filterability equal to that of water.
- Myoglobin is only partially filtered (75% to that of water)