MDS PREP
What hormone is secreted by the kidneys that stimulates red blood cell production?
1) Renin
2) Erythropoietin
3) Aldosterone
4) Cortisol
Erythropoietin is the hormone secreted by the kidneys that stimulates red blood cell production in response to low oxygen levels in the blood.
What is the primary effect of insulin on the skeletal muscles?
1) Stimulation of protein synthesis
2) Increased glycolysis
3) Increased glucose uptake and glycogen synthesis
4) Stimulation of muscle contraction
Answer: 3) Increased glucose uptake and glycogen synthesisExplanation: Insulin stimulates glucose uptake by muscle cells and promotes glycogen synthesis. It does so by increasing the number of glucose transporters on the muscle cell membrane and facilitating the transport of glucose into the cells.
What is the role of troponin in skeletal muscle contraction?
1) It initiates contraction by binding to calcium ions
2) It is essential for the sliding of actin and myosin filaments
3) It is involved in the excitation-contraction coupling process
4) It is not present in skeletal muscles and plays no direct role in their contraction
Troponin is a protein complex found in cardiac and smooth muscles, not in skeletal muscles. In skeletal muscles, it is the regulatory proteins tropomyosin and the troponin complex that are crucial for excitation-contraction coupling.
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
Ultraviolet B (UVB) light is primarily responsible for the conversion of 7-dehydrocholesterol to cholecalciferol (vitamin D3) in the skin.
What is the primary function of the somatic sensory area of the parietal lobe?
1) Auditory perception
2) Visual perception
3) Somatic sensation interpretation
4) Olfactory perception
The somatic sensory area of the parietal lobe, particularly Brodmann's areas 3, 1, and 2, is involved in the interpretation of tactile, proprioceptive, and other sensory information from the body.
The primary function of the afferent arterioles in the juxtaglomerular apparatus is to:
1) Constrict in response to increased sodium chloride delivery
2) Dilate in response to increased sodium chloride delivery
3) Secrete renin in response to decreased sodium chloride delivery
4) Constrict in response to decreased sodium chloride delivery
The afferent arterioles are part of the juxtaglomerular apparatus along with the macula densa and efferent arterioles. When the macula densa detects a decrease in sodium chloride delivery, it triggers the juxtaglomerular cells in the afferent arterioles to release renin, which is the initial step in the RAAS.
What type of sleep is associated with sleep spindles and K complexes?
1) Stage 1 NREM
2) Stage 2 NREM
3) Stage 3 NREM
4) REM sleep
While sleep spindles and K complexes are prominent in Stage 2 NREM sleep, they can also be present in the transition between wakefulness and sleep, which is considered part of Stage 1 NREM sleep.
What is the effect of vitamin E deficiency on cell membranes?
1) Increased fluidity
2) Decreased fluidity
3) No change in fluidity
4) Unknown
Vitamin E deficiency can lead to decreased fluidity of cell membranes, making them less flexible and more prone to damage.