BCSE Veterinary Anatomy and Physiology 4 — Questions and Answers
Question 1: Which cell type in the gastric mucosa of dogs and cats secretes hydrochloric acid?
- Chief (zymogenic) cells
- Mucous neck cells
- G cells
- Parietal (oxyntic) cells (Correct answer)
Correct answer: Parietal (oxyntic) cells
Parietal (oxyntic) cells secrete hydrochloric acid via H+/K+-ATPase pumps, creating the highly acidic gastric environment needed for protein digestion.
Question 2: The annular ligament of the radius stabilizes which joint in domestic animals?
- Shoulder joint
- Proximal radioulnar joint (elbow) (Correct answer)
- Carpus
- Distal radioulnar joint
Correct answer: Proximal radioulnar joint (elbow)
The annular ligament encircles the radial head, holding it against the ulna at the proximal radioulnar joint and maintaining elbow stability.
Question 3: In mammals, which region of the nephron is primarily responsible for active sodium reabsorption driven by Na+/K+-ATPase on the basolateral membrane?
- Glomerulus
- Proximal convoluted tubule (Correct answer)
- Loop of Henle thin descending limb
- Collecting duct
Correct answer: Proximal convoluted tubule
The proximal convoluted tubule reabsorbs approximately 65–70% of filtered sodium via Na+/K+-ATPase on the basolateral surface, with other solutes following osmotically.
Question 4: Which neurotransmitter is released at the neuromuscular junction of skeletal muscle in mammals?
- Norepinephrine
- Dopamine
- Acetylcholine (Correct answer)
- Serotonin
Correct answer: Acetylcholine
Acetylcholine is released from motor neuron terminals and binds nicotinic receptors on the motor end plate, initiating muscle contraction.
Question 5: In horses, the 'stay apparatus' of the hindlimb locks the stifle and hock in which position, allowing standing sleep?
- Flexed
- Extended (Correct answer)
- Abducted
- Adducted
Correct answer: Extended
The reciprocal apparatus and stay apparatus lock the stifle and hock joints in extension with minimal muscular effort, enabling horses to sleep standing up.
Question 6: Which cardiac valve prevents backflow of blood from the aorta into the left ventricle during diastole?
- Mitral valve
- Pulmonary valve
- Tricuspid valve
- Aortic semilunar valve (Correct answer)
Correct answer: Aortic semilunar valve
The aortic semilunar valve has three cusps that snap shut during ventricular diastole, preventing regurgitation of blood from the aorta into the left ventricle.
Question 7: Which type of bone cell is responsible for the resorption of bone matrix and is derived from monocyte/macrophage precursors?
- Osteoblast
- Osteocyte
- Osteoclast (Correct answer)
- Periosteal fibroblast
Correct answer: Osteoclast
Osteoclasts are large, multinucleated cells derived from monocyte/macrophage precursors that secrete acid and proteases to resorb mineralized bone matrix.
BCSE Veterinary Anatomy and Physiology 4
Which cell type in the gastric mucosa of dogs and cats secretes hydrochloric acid?