mark answer and give a brief explanation why you gave that answer 9. If blood fl
ID: 16303 • Letter: M
Question
mark answer and give a brief explanation why you gave that answer9. If blood flow through the afferent arterioles increases,
A. stretch reflexes trigger vasoconstriction to reduce the flow.
B. stretch-activated calcium channels, within the afferent arteriole smooth muscle cells, close.
C. the smooth muscle in the vessel walls stretches to accommodate the increased flow.
D. the stretch triggers further relaxation of the arteriolar wall, lessening blood pressure.
E. A and B
10. Stimuli for the activation of the RAAS (Renin-Angiontensin-Aldosterone System) pathway include
A. low blood pressure in afferent arterioles.
B. a decrease in fluid flow through the distal tubule.
C. low blood pressure in carotid arteries.
D. A and B
E. A, B, and C
Explanation / Answer
9 Answer is the option E
Explanation:
When renal blood flow is reduced or there is a decrease in sodium and chloride ion concentration, the macula densa of the distal tubule releases prostaglandins, which cause the juxtaglomerular cells lining the afferent arterioles to release renin, activating the renin-angiotensin-aldosterone system, to increase blood pressure and increase retention of sodium ions via aldosterone.
The macula densa cell can also increase the local blood pressure of the afferent arterioles by increasing the synthesis of nitrous oxide or decreasing the synthesis of adenosine or ATP.
If the afferent arterioles are constricted then the blood pressure in the capillaries of the kidneys will drop. They consist of blood plasma.
10 Answer is E
The RAS is composed of several neuronal circuits connecting the brainstem to the cortex. These pathways originate in the upper brainstem reticular core and project through synaptic relays in the rostral intralaminar and thalamic nuclei to the cerebral cortex.[4] As a result, individuals with bilateral lesions of thalamic intralaminar nuclei are lethargic or somnolent.[1] Several areas traditionally included in the RAS are:[5][6]
The RAS consists of evolutionarily ancient areas of the brain, which are crucial to survival and protected during adverse periods. As a result, the RAS still functions during inhibitory periods of hypnosis.[7]
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.