MDS PREP
MCQ: The physiological capacity of the bladder, at which micturition is normally effected, ranges between:
1) 150 ml - 250 ml
2) 250 ml - 450 ml
3) 450 ml - 750 ml
4) 750 ml - 1000 ml
The physiological capacity of the bladder, at which micturition is normally effected, ranges between 250 ml - 450 ml, indicating the volume at which the urge to urinate is felt.
What is the primary neurotransmitter of the sympathetic nervous system?
1) Acetylcholine
2) Norepinephrine
3) Dopamine
4) Epinephrine
The sympathetic nervous system primarily uses norepinephrine (also known as noradrenaline) as its neurotransmitter. It is released from the synaptic terminals of postganglionic sympathetic fibers and acts on adrenergic receptors, which are found on various target cells throughout the body. This neurotransmitter is essential for the body's "fight or flight" response, contributing to increased heart rate, dilated pupils, and other physiological changes associated with stress or emergency situations.
Which of the following inhibits gastric acid secretion?
1) Low pH in the stomach
2) High pH in the duodenum
3) Secretion of gastrin
4) Both A and B
Physiology
Answer: 4
Gastric acid secretion is inhibited by acidification of the stomach and duodenum. Low pH (acidity) in the stomach inhibits gastrin release from G cells, while high pH in the duodenum also contributes to the negative feedback mechanism that reduces acid secretion.
What is the condition characterized by the lack of intrinsic factor, leading to vitamin B12 malabsorption?
1) Pernicious anemia
2) Celiac disease
3) Lactose intolerance
4) Crohn's disease
Pernicious anemia is characterized by the lack of intrinsic factor, leading to vitamin B12 malabsorption and subsequent anemia.
What is the primary function of the neck in a sperm cell?
1) It connects the head and tail of the sperm
2) It produces the sperm's energy for movement
3) It is responsible for the fertilization process
4) It contains the cell's genetic material
Physiology
Answer: 1
The neck of the sperm cell is a small structure that connects the head, which contains the nucleus with the chromosomes, to the tail, which is responsible for the sperm's movement.
What happens when the transport maximum for glucose is exceeded?
1) All excess glucose is reabsorbed
2) Some glucose is reabsorbed and some is excreted
3) All excess glucose is excreted in the urine
4) No glucose is excreted regardless of the amount
When the transport maximum for glucose is exceeded, some glucose is reabsorbed and some is excreted in the urine, leading to glucosuria.
What is the role of ghrelin in the control of food intake?
1) It stimulates the release of growth hormone
2) It suppresses the secretion of gastric acid
3) It inhibits food intake
4) It increases the sensation of hunger
Ghrelin increases the sensation of hunger, stimulating appetite and food intake, particularly before meals.
What is the primary site of vitamin B12 absorption in the intestine?
1) Stomach
2) Duodenum
3) Jejunum
4) Ileum
Physiology
Answer: 4
The ileum is the primary site of vitamin B12 absorption, facilitated by intrinsic factor binding to specific receptors.