MCQ Snacks - (Free trial) - Physiology | Attempts: 195

2.

Aldosterone receptors are present in all except

Liver
Colon
Hippocampus
Distal nephron

Correct Answer

A. Liver

3.

Pulmonary circulation differs from systemic circulation

Pulmonary vasodilation in hypoxia
Pulmonary vasoconstriction in hypoxia
Decreased blood volume during systole
Increased basal vasoconstrictor tone

Correct Answer

A. Pulmonary vasoconstriction in hypoxia

Explanation

In hypoxia, the body's response is to constrict the blood vessels in the lungs, known as pulmonary vasoconstriction. This helps to redirect blood flow to areas of the lungs that are better oxygenated, improving the efficiency of gas exchange. This is in contrast to systemic circulation, where vasodilation occurs in response to hypoxia to increase blood flow to tissues and organs.

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4.

Increase in threshold level of a nerve on application of a slowly rising sub-threshold stimulus is known as:

Adaptation
Accomodation
Refractoriness
Electrotonus

Correct Answer

A. Accomodation

Explanation

Accommodation refers to the increase in threshold level of a nerve when a slowly rising sub-threshold stimulus is applied. This phenomenon allows the nerve to adapt to the gradually increasing stimulus and eventually reach its threshold level, resulting in an action potential. This process is important for the nerve to properly respond to varying levels of stimuli and maintain its sensitivity.

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5.

Which of the following is true about fourth heart sound ‘S4‘ :

Can be heard by the unaided ear
Frequency is greater than 20 Hz
Heard during ventricular filling phase
Heard during ventricular ejection phase

Correct Answer

A. Heard during ventricular filling phase

Explanation

S4 is heard during the last rapid filling phase of cardiac cycle.

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6.

Broca’s area is concerned with:

Word formation
Comprehension
Repetition
Reading

Correct Answer

A. Word formation

Explanation

Broca's area is the motor speech area concerned with word formation.

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7.

All of the following statements are true for ‘Intestinal Motility’ except:

Does not depend on Gastric motility
Increased by Distension
Increased by Acetylcholine
Increased by cholecystokinin

Correct Answer

A. Does not depend on Gastric motility

Explanation

Intestinal motility is influenced by gastric motility. eg: Migratory motor complex, gastroileal reflex

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8.

Which of the following hormone is not secreted by the kidney:

Renin
Angiotensin I
Erythropoietin
1, 25 Dihydroxycholecalciferol

Correct Answer

A. Angiotensin I

Explanation

Angiotensin I is formed by action of Renin (secreted by kidney) on Angiotensinogen (secreted by liver).

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9.

When a muscle cell is relaxed and intracellular ATP levels are normal, a crossbridge will remain in which of the following states?

Bound to actin and in the low-energy form
Bound to actin and in the high-energy form
In the high-energy form, with ADP and Pi bound to it
In the high-energy form, with ATP bound to it

Correct Answer

A. In the high-energy form, with ADP and Pi bound to it

Explanation

When a muscle cell is relaxed and intracellular ATP levels are normal, a crossbridge will remain in the high-energy form with ADP and Pi (inorganic phosphate) bound to it. This is because during muscle contraction, ATP is hydrolyzed into ADP and Pi, releasing energy that is used to power the movement of the crossbridge. In the relaxed state, the crossbridge is still bound to actin but is in the high-energy form, ready to undergo the power stroke and generate force when the muscle is stimulated to contract.

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10.

Which of the following is true for the excitation-contraction coupling of all muscle types (skeletal, cardiac, and smooth)?

An action potential causes calcium levels in the cytosol to increase
Calcium binds to troponin
Thick and thin filaments slide past each other
A & c

Correct Answer

A. A & c

Explanation

During excitation-contraction coupling in all muscle types, an action potential is generated, which causes calcium levels in the cytosol to increase. This increase in calcium levels then leads to the binding of calcium to troponin, resulting in the exposure of binding sites on actin. Subsequently, the thick and thin filaments slide past each other, leading to muscle contraction. Therefore, both options "a" (an action potential causes calcium levels in the cytosol to increase) and "c" (thick and thin filaments slide past each other) are true for the excitation-contraction coupling of all muscle types.

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MCQ Snacks - (Free Trial) - Physiology

ln isometric exercise all are increased except :

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Aldosterone receptors are present in all except

Pulmonary circulation differs from systemic circulation

Increase in threshold level of a nerve on application of a slowly rising sub-threshold stimulus is known as:

Which of the following is true about fourth heart sound ‘S4‘ :

Broca’s area is concerned with:

All of the following statements are true for ‘Intestinal Motility’ except:

Which of the following hormone is not secreted by the kidney:

When a muscle cell is relaxed and intracellular ATP levels are normal, a crossbridge will remain in which of the following states?

Which of the following is true for the excitation-contraction coupling of all muscle types (skeletal, cardiac, and smooth)?