Anatomy and Physiology MCQs

Body Temperature, Energy and Heat Loss

What is the reason that the temperature of a substance does not rise while it is in the act of melting, even if heat is added to it?

Melting will not occur until the latent heat of vaporisation has been sup-plied; this prevents a rise in temperature until all the solid has melted.

The added heat energy is used to increase the vibrational and rotational kinetic energies rather than the temperature (i.e. translational kinetic energy) of the particles.

The presence of colder unmelted particles alongside particles that are in liquid form causes their temperature to remain low.

Any energy added to the substance is used to break the bonds that hold the particles into the solid form so it does not contribute to a temperature rise.

Once the bonds between the adjacent particles of a solid have been broken, they are free to move about, and the particles can increase their kinetic energy, that is, the rise in temperature.

Author: rikazzz Comment

Cardiovascular System

The volume of gas trapped within a space will increase as pressure decreases; the physics law that refers to this is:

Henry’s law

Poiseuille’s law

Hugh’s law

Boyle’s law

Boyle’s law relates gas pressure and gas volume.

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Integument

What are three functions of the skin? To:

Store fat, produce sebum, trap a layer of air beneath hair to insulate against heat loss

Synthesise vitamin D, excrete bile, protect against abrasion

Produce melanin, regulate body temperature, minimise water loss

Produce keratin, assist in the immune response, produce dendrocytes

Fat is not stored in the skin. Bile is not excreted. Dendrocytes are not produced.

Author: rikazzz Comment

Endocrine System

What effect does insulin have?

It increases metabolic rate.

It causes the breakdown of glycogen to glucose.

It lowers blood sugar level.

It stimulates gluconeogenesis.

Glucose stimulates enhanced membrane transport of glucose into body cells and inhibits glycogenolysis and gluconeogenesis. This lowers blood glucose level.

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Skeleton and Joints

What is the metaphysis?

The shaft of a long bone

The region that separates the narrow shaft of a long bone from its end

The end of a long bone

The canal inside a long bone that contains marrow

The metaphysis is the bony remnant of the growth plate. The cartilaginous component of the growth plate is the epiphyseal plate.

Author: rikazzz Comment

Gastrointestinal System

What is the function of bile?

Bile hydrolyses polypeptides.

Bile emulsifies fats and oils.

Bile activates procarboxypeptidase.

Bile stimulates the pancreas to secrete pancreatic juice.

Emulsification of fats is the function of bile salts.

Author: rikazzz Comment

Gastrointestinal System

What are the products of protein digestion?

Monoglycerols and fatty acids

Dipeptides, tripeptides and amino acids

Bases, pentose sugars and nitrate ions

Monosaccharides and disaccharides

Peptides and amino acids are produced by the hydrolysis of protein.

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Renal System

What is the effect of antidiuretic hormone on the kidney tubules?

It causes Na+ to be absorbed from the filtrate into the tubular cells.

It causes the concentration of urine to decrease.

It causes the filtrate volume to increase.

It causes the walls of the collecting duct to become permeable to water.

ADH causes more water channels (aquaporins) to be inserted in the wall of the collecting duct. Hence, the duct is more permeable to water.

Author: rikazzz Comment

Cardiovascular System

Where is the mitral valve of the heart located? Between the:

Left atrium and left ventricle

Left ventricle and the aorta

Right ventricle and the pulmonary trunk

Right atrium and right ventricle

The mitral valve is the left atrioventricular valve.

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

Given the formulae speed = frequency × wavelength (v = fλ) and frequency is one over the period (f = 1/T), what is the wavelength of a light wave (speed = 3 × 10⁸ m/s) whose period is 2 × 10−¹⁵ s?

1.5 × 10−⁷ m

6 × 10−⁷ m

1.67 × 10⁶ m

1.5 × 10²³ m

First determine the frequency: f = 1/T = 1/(2 × 10−¹⁵) = 0.5 × 10¹⁵ Hz. Then rearrange the wave equation for wavelength: v = fλ so λ = v/f.
Then substitute the numbers: λ = v/f = 3 × 10⁸ m/s ÷ 0.5 × 10¹⁵ Hz = 6 × 10−⁷ m.

Author: rikazzz Comment