Anatomy and Physiology MCQs

Gastrointestinal System

Which of the following substances is NOT produced by the cells of the gastric glands?

Mucus

Hydrochloric acid

Gastrin

Pepsin

Mucus cells are in the epithelium, not in the gastric glands, and produce mucus.

Author: rikazzz Comment

Renal System

In the kidney, the filtrate passes through several structures on its way to becoming urine. Which of the following lists presents these structures in the correct order?

Collecting duct, glomerulus, proximal convoluted tubule, distal convo-luted tubule, loop of Henle

Proximal convoluted tubule, collecting duct, glomerulus, loop of Henle, distal convoluted tubule

Glomerulus, proximal convoluted tubule, loop of Henle, distal convoluted tubule, collecting duct

Glomerulus, collecting duct, proximal convoluted tubule, distal convo-luted tubule, loop of Henle

Glomerulus must precede the collecting duct. Collecting duct must be after the DCT.

Author: rikazzz Comment

Electricity

Ohm’s law may be stated in the form: “the current flowing in a circuit is the potential difference divided by the electrical resistance in the circuit”. If a person whose hand-to-hand resistance is 80,000 Ω touches a live wire (attached to 240 V mains supply) and a wall at the same time, what is the magnitude of the current that will flow through the chest?

3 mA

30 mA

300 mA

3000 mA

Ohm’s law as stated is: I = V ÷ R putting in the numbers gives: I = V ÷ R = 240 ÷ 80,000 = 0.003A = 3 mA.

Author: rikazzz Comment

Nervous System

What is the correct statement when applied to the myelin sheath?

It is produced by ependymal cells.

It allows rapid impulse transmission by saltatory conduction.

It insulates the axon by surrounding it with protein.

It surrounds the dendrites of a neuron.

Saltatory conduction refers to the action potential “jumping” from node to node of a myelinated neuron. Myelin is a lipid, not a protein. Myelin surrounds the axon, not the dendrite. (The peripheral sensory neurons have myelinated dendrites. Short dendrites in the central nervous system are not myelinated.)

Author: rikazzz Comment

Nervous System

Which statement about the vagus nerve is true?

It lies within the cerebrospinal tract.

It arises from the pons.

It has a sensory function in vision and olfaction.

It carries parasympathetic motor impulses.

The vagus nerve carries 90% of parasympathetic motor impulses. It arises mainly from the medulla oblongata.

Author: rikazzz Comment

Respiratory System

At a height of 3000 m above sea level, atmospheric pressure is 30 kPa less than at sea level. A consequence of this lower pressure is that less oxygen will dissolve in the alveolar fluid. The reason for this is that:

The solubility coefficient of oxygen is lower.

The partial pressure of oxygen in the atmosphere is lower.

Water vapour evaporating from the lung will exert a greater partial pressure.

There will be more carbon dioxide leaving the blood and entering the alveoli.

At 3000 m, atmospheric pressure is 70 kPa, and the oxygen partial pressure is 20% of this (about 14 kPa). 14 kPa is less than 20 kPa (oxygen’s partial pressure at sea level), so less oxygen will dissolve in the alveolar fluid at 3000 m than at sea level.

Author: rikazzz Comment

Cardiovascular System

To what does the term ventricular systole refer?

Relaxation of the ventricles

Relaxation of the atria

Contraction of the myocardium

Contraction of the ventricles

Ventricular systole is contraction of the ventricles, which does not coincide with relaxation of the atria.

Author: rikazzz Comment

Renal System

Which one of the following is part of the renal tubule?

Glomerulus

Vasa recta

Collecting duct

Macula densa

The macula densa consists of cells in the wall of the distal convoluted tubule at the juxtaglomerular apparatus.

Author: rikazzz Comment

Cells and Tissues

Which of the following cells would be found in nervous tissue?

Dendrocytes

Microglia

Microphages

Erythrocytes

Microglia is a term that refers to the support cells of the nervous system. Dendrocytes are found in the epidermis and there are no erythrocytes in the CNS.

Author: rikazzz Comment

Measurement, Errors, Data and Unit Conversion

What is the “average” wage – technically referred to as the arithmetic mean?

$475

$500

$526

$5260

The arithmetic mean is the sum of the ten wages, divided by the number of wages (10). So $5260 ÷ 10 = $526.

Author: rikazzz Comment