Anatomy and Physiology MCQs

Temperature is a measure of the average kinetic energy of the particles of the object.

Temperature is the amount of heat energy contained within the object.

Temperature is the amount of energy that flows from the object being measured to the thermometer.

Temperature is a measure of the hotness (or coldness) of the object.

The faster the particles of an object are vibrating, the higher is its temperature. Temperature is the average kinetic energy of its particles.

Author: rikazzz Comment

The Physics of Waves: Light Waves, Sound Waves and Ultrasound

What is a concave lens? One that:

Can accommodate to different focal lengths

Will cause light rays to converge

Is thicker in the middle than at the edge

Will correct for myopia (short-sightedness)

Concave lens will cause light rays to diverge. So it can be used to correct short-sightedness as they shift the focal point further away from the eye’s lens.

Author: rikazzz Comment

Respiratory System

Trauma that severs the spinal cord between C6 and C7 will:

Mean that the phrenic nerve has been severed

Mean that artificial ventilation will be required to sustain life

Cause the diaphragm to lose innervation but allow the intercostal muscles to operate

Cause the intercostal muscles to lose innervation but allow the diaphragm to operate

The phrenic nerve that stimulates the diaphragm will not be severed as the spinal nerves that form it leave the spinal cord above C6. The intercostal muscles will be paralysed.

Author: rikazzz Comment

Nervous System

What do the descending tracts of the spinal cord contain?

White matter and transmit sensory information

White matter and transmit motor commands

Grey matter and transmit sensory information

Grey matter and transmit motor commands

Tracts refer to axons which are encased in myelin which makes them look white. Descending refers to impulses that carry information from the brain to the body (motor commands) usually to muscle.

Author: rikazzz Comment

Biomechanics

In which of the following situations is an unbalanced force acting on a patient’s body? When the patient is:

Lying stationary and supine on the bed

Lying stationary and supine on the bed, while the bed is being pushed a constant speed along a straight corridor

Being assisted to sit still and upright on the edge of the bed

Lying stationary and supine on the bed, while the bed is being pushed around a corner in a corridor

Changing the direction of motion by turning a corner (even if the speed does not change) requires an unbalanced force. Being still or moving at constant speed indicates that there are no unbalanced forces acting.

Author: rikazzz Comment

Cardiovascular System

Which of the following does angiotensin II cause to happen?

Atrial natriuretic peptide to be released

The collecting ducts in the kidney to become permeable to water

The release of antidiuretic hormone to be supressed

Aldosterone to be released

Angiotensin II stimulates the adrenal glands to release aldosterone.

Author: rikazzz Comment

Respiratory System

What happens when carbon dioxide levels in the blood decrease to below normal?

pH of the blood decreases.

The blood becomes more acidic.

The concentration of hydrogen ions in the blood decreases.

pH does not change.

Carbon dioxide reacts with water to form carbonic acid and thence hydronium ions. So a decrease in CO₂ will decrease the concentration of hydronium ions (and pH will increase).

Author: rikazzz Comment

Chemistry for Physiology

Only one of the definitions of osmotic pressure below is correct. Which one?

The hydrostatic pressure required to halt osmosis is called osmotic pressure.

Water pressure that develops in a solution as a result of osmosis into that solution is called osmotic pressure.

Osmotic pressure is the pressure exerted by the movement of water across a semipermeable membrane due to the difference in solution concentration.

Osmotic pressure is the force required to prevent water from moving by osmosis across a selectively permeable membrane.

The other three choices, despite all being quotations from anatomy and physiology textbooks, are wrong. Osmotic pressure is not a force; water movement does not exert a pressure; osmosis between compartments in the body does not cause water pressure to develop.

Author: rikazzz Comment

Reproductive System

One of the following is NOT a secondary sex characteristic. Which one?

The adult male body shape

The thicker vocal cords of a male

Pubic hair

The penis

Secondary sex characteristics are those that develop after puberty, that is, not present at birth.

Author: rikazzz Comment

Respiratory System

Given that the partial pressures of oxygen and of carbon dioxide in blood entering the alveolar capillaries are pO₂ = 40 mmHg and pCO₂ = 46 mmHg, respectively, and that the air in the alveoli contains pO₂ = 104 mmHg and pCO₂ = 40 mmHg, which of the following will happen?

O₂ will diffuse from alveoli into blood, and CO₂ will diffuse into alveoli from blood.

Both O₂ and CO₂ will diffuse from alveoli into blood.

Both O₂ and CO₂ will diffuse from blood into alveoli.

CO₂ will diffuse from alveoli into blood and O₂ will diffuse into alveoli from blood.

Oxygen will diffuse from where it is in high concentration (104 mmHg in alveolar fluid) to where it is in lower concentration (40 mmHg in venous blood).
CO₂ will diffuse from blood (where it is at 46 mmHg) into the alveolar fluid (where it is at 40 mmHg). From the alveolar fluid, CO₂ will vaporise into the alveoli for exhalation.

Author: rikazzz Comment