Question

Bone marrow (select the MOST CORRECT statement)

		Red bone marrow is a tissue that contains pluripotent stem cells.
		Both neutrophils and red blood cells develop in red bone marrow.
		Platelets are fragments of megakaryocytes that form in yellow bone marrow.
		Both a) and b) are correct and c) is incorrect
		a), b) and c) are all correct

Select the MOST CORRECT answer.

		GFR remains stable at 180 L / day despite fluctuations in MAP due to the myogenic response and tubuloglomerular feedback.
		GFR remains stable at 180 L / day despite fluctuations in MAP due to the release of paracrine factors from macula densa cells.
		GFR remains stable at 180 L / day despite fluctuations in MAP due to afferent arteriole smooth muscle stretch response.
		Both a) and b) are correct and c) is incorrect.
		a), b) and c) are all correct.

Answer 1

The most correct answer is both A & B are correct and C is correct,

Explaination:

Pluripotent stem cells are present in umbilical cord blood and other tissues in red bone marrow, both neutrophils and red blood cells in red bone marrow.

Neutrophils is produced by bone marrow which regulates the cytokine granulocyte colony stimulating factor (G-CSF) and continuously released in the blood circulation and red blood cells called hemocytoblasts which are responsible and give rise to all of the formed elements in blood and formation of new red blood cell.

C is correct because red color bone marrow observe in developing stage of human body, after due to fat deposition in adipose tissue it gives yellow color mostly observed in adults. Platelets, small blood cell fragments involved in clotting which is formed giant marrow cells known as megakaryocytes. The new blood cells which are released into the sinusoids, large thin-walled vessels that drain into the veins of the bone. Blood formation in adults takes place mainly in the bone marrow.

Answer:

Both A & B are correct and C incorrect.

Tubuloglomerular feedback which is referred as feedback regulation of the GFR in a single nephron based on the sensory information about distal tubule fluid is stable at 180L/ day

These paracrine mediators contract nearby smooth muscle cells in the afferent arteriole to reduce RBF and, thus, return GFR to normal and is stable

An increase in hydrostatic pressure in the afferent arteriole stretches vascular smooth muscle, activating inward directed ion channels, leading to depolarization and contraction. This prevents pathologic increases in RBF that would damage the kidney.

Thank you............