MDS PREP
Which hypothalamic nucleus is considered the satiety center?
1) Venteromedial nucleus
2) Lateral nucleus
3) Arcuate nucleus
4) Dorsomedial nucleus
Answer: 1) The venteromedial nucleus of the hypothalamus is considered the satiety center.
Which of the following statements is true about the regulation of the sympathetic nervous system?
1) The sympathetic nervous system is primarily regulated by the parasympathetic nervous system.
2) The sympathetic nervous system is mainly controlled by the hypothalamus.
3) The sympathetic nervous system is regulated by the spinal cord through the sympathetic chain ganglia.
4) The sympathetic nervous system is primarily regulated by the sympathetic chain ganglia.
Answer: 3) The sympathetic nervous system is regulated by the spinal cord through the sympathetic chain ganglia, which receive input from the hypothalamus and other higher centers.
Most of the pre ganglionic sympathetic fibres are
1 A fibres
2 B fibres
3 C Fibres
4 None of the above
Physiology
Answer: 2
- A fibres are myelinated fibres having fastest rate of conduction
What sleep stage is characterized by beta-wave activity on EEG, dreaming, and generalized muscular atonia?
1) Stage 1 NREM
2) Stage 2 NREM
3) REM sleep
4) Stage 3 NREM
REM sleep is characterized by beta-wave activity, dreaming, and muscular atonia, which is a state of almost complete paralysis except for the muscles controlling eye movement, respiration, and other involuntary processes.
The glomerular filtration barrier consists of:
1) Endothelial cells
2) Basement membrane
3) Podocytes
4) All of the above
The glomerular filtration barrier is a three-layered structure composed of endothelial cells of the glomerular capillaries, the basement membrane, and the podocytes (visceral epithelial cells of Bowman's capsule). These layers work together to filter blood, allowing small molecules to pass into the nephron while retaining larger ones.
Which hormone is primarily responsible for the conversion of 7-dehydrocholesterol to cholecalciferol in the skin?
1) Parathyroid hormone (PTH)
2) Vitamin D
3) Ultraviolet B (UV2) light
4) 25-hydroxyvitamin D3
Physiology
Answer: 3
The conversion of 7-dehydrocholesterol to cholecalciferol (vitamin D3) in the skin is initiated by the action of UVB light from sunlight, not by any specific hormone.
In which brain regions are Broca's and Wernicke's areas located?
1) Inferior temporal gyrus and superior parietal gyrus
2) Inferior frontal gyrus and superior temporal gyrus
3) Superior frontal gyrus and middle temporal gyrus
4) Inferior parietal lobule and superior occipital gyrus
Answer: 2) Broca's area is located in the inferior frontal gyrus and is involved in motor speech, while Wernicke's area is located in the superior temporal gyrus and is associated with language comprehension.
Norepinephrine is stored at the
1. Preganglionic parasympathetic nerve endings
2. Postganglionic parasympathetic nerve endings
3. Preganglionic sympathetic nerve endings
4. Postganglionic sympathetic nerve endings
Physiology
Answer: 2
Norepinephrine is stored at the Postganglionic parasympathetic nerve endings