Anatomy and Physiology MCQs

Skeleton and Joints

Which of the listed bones is superior to the rest?

Manubrium

Xiphoid process

Coccyx

Femur

The manubrium is the upper part of the sternum. The xiphoid process is the lower part.

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Biomechanics

What is the reason that a third-class lever is inefficient?

The muscle’s effort force is applied closer to the fulcrum than the load force.

The load force is applied closer to the fulcrum than the muscle’s effort force.

The fulcrum separates the effort from the load.

The load force is greater than the muscle’s effort force.

Consider flexing the forearm using the biceps brachii. Its tendon is inserted on the radius bone very close to the elbow joint, while the load (the forearm) is further away. Such an arrangement allows a short contraction of the biceps brachii to be converted to a large sweep of motion of the hand.

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Cardiovascular System

If a stenosis reduces the size of a blood vessel to half of the original diameter, the volume flow rate through the vessel will be reduced. Which relationship below determines the extent of the decrease in flow?

Poiseuille’s law

Bernoulli’s theorem

Dalton’s law

Pascal’s principle

Poiseuille’s law relates diameter (radius) of blood vessel to volume flow rate.

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Gastrointestinal System

How are the pH of the small intestine and the pH of the stomach (respectively) best described?

Alkaline (basic) and acidic

Weakly alkaline (basic) and strongly acidic

pH of 4 and pH of 8

pH of 7 and pH of 1.5

The pH of the stomach contents is about 2 (strongly acidic), while the pH of the small intestine is about 8 (weakly alkaline). The numbers in choices C and D are wrong. Thus B is the best answer.

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Respiratory System

What does sympathetic nervous system stimulation to the smooth muscle layers in the bronchioles cause?

Bronchoconstriction

Bronchodilation

An increase in tidal volume

Increase in activity of the cilia

Bronchodilation is stimulated by sympathetic nerve impulses, adrenalin and noradrenalin. Bronchoconstriction is triggered by parasympathetic nerve impulses.

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Reproductive System

The hormone progesterone is released by which structure?

Anterior pituitary

Corpus luteum

Hypothalamus

The adrenal glands

If progesterone was produced by any of the other structures, then men would have it too.

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Chemistry for Physiology

Twenty-four of the chemical elements are essential to the human body. Four are bulk elements, 7 are macrominerals and 13 are trace elements. Which are the four bulk elements?

Calcium, carbon, hydrogen and oxygen

Nitrogen, carbon, hydrogen and oxygen

Calcium, nitrogen, carbon and oxygen

Carbon, oxygen, phosphorus and iron

These elements make up the bulk of proteins, carbohydrates and lipids.

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Cardiovascular System

Which liquid below has the greatest volume in the body?

Blood

Plasma

Serum

Extracellular fluid

Extracellular fluid includes blood and all other liquids not contained in cells. Plasma is serum plus the clotting factors. Blood is plasma plus RBC and WBC.

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Muscles

Microscopically, muscle fibres contain parallel myofibrils. What are the units joined end to end within a myofibril called?

Myofilament

Motor unit

Myosin

Sarcomere

Sarcomeres joined end to end, like train carriages, form a myofibril.

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Cardiovascular System

How is the fibrous pericardium attached to the surrounding structures?

Laterally to the pleural surfaces of the lungs

Posteriorly to the sternum

Anteriorly to trachea, main-stem bronchi and oesophagus

Inferiorly to the clavicles

The only sensible answer when anatomical position terminology is used. The lungs are lateral to the heart. The sternum is not posterior to the heart; the trachea and oesophagus are. The heart is not attached to the clavicles.

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