Question

Adrenaline directly affects.
A. SA node
B. beta cells of Langerhans
C. Dorsal root of spinal nerve
D. Epithelial cells of stomach

Answer 1

Hint:- Adrenaline also called epinephrine is a type of amine hormone. It is also used as an emergency medication. Adrenaline is produced by both the adrenal medulla and neurons in the medulla oblongata, where it acts as a neurotransmitter involved in visceral functions in the body.

Complete Answer:-Adrenaline prepares the body for emergency alarming reactions like fight and flight. it directly affects the SA node to increase the rate of heartbeat. The adrenal medulla secretes adrenaline which directly affects the SA node thereby increases the heart rate. It is responsible for the alarming reactions and also increases breathing rate and blood glucose level, blood pressure, peripheral circulation, etc.
The beta cells of the Islets of Langerhans of the pancreas produce the endocrine hormone insulin. It controls human blood glucose levels, glucose, and fat metabolism in the body.
The dorsal root of the spinal nerve also known as the posterior root of the spinal nerve. It is a root that emerges from the spinal cord and travels up to the dorsal root ganglion. Whereas the Nerve fibres with the ventral root then combine to form a spinal nerve.
Four major types of secretory epithelial cells cover the surface of the stomach and extend further down into gastric pits and glands: Mucous cells which secrete alkaline mucus which protects the gastric epithelium against shear stress and acid. Parietal cells which secrete hydrochloric acid. Chief cells which secrete a proteolytic enzyme called pepsin.

So, the correct option is (A) S.A Node

Note:- The sympathomedullary called the SAM pathway involves the stimulation of the adrenal medulla by impulses from the hypothalamus via neural networks from the thoracic spinal cord. The medulla is thus stimulated to secrete the epinephrine and norepinephrine to respond to stress.