Question

question 18
1 pts
what is the difference between a somatic reflex and an autonomic reflex?
a somatic reflex is caused by contraction of smooth or cardiac muscles, whereas an autonomic reflex consists of skeletal muscle contraction.
a somatic reflex is caused by the secretions of glands, whereas an autonomic reflex consists of contraction of smooth and skeletal muscles.
a somatic reflex is caused by contraction of skeletal muscles, whereas an autonomic reflex consists of contraction of smooth or cardiac muscle or secretions of glands.
a somatic reflex is caused by contraction of smooth or cardiac muscles, whereas an autonomic reflex consists of the secretions of glands.
question 19
1 pts
sympathetic responses generally have widespread effects on the body because:
they reach visceral effectors faster than parasympathetic impulses.
myoneural junctions contain a substance that inactivates acetylcholine.
preganglionic fibers are short and postganglionic fibers are long.
preganglionic fibers synapse with several postsynaptic fibers.

Explanation:

• Question 18: Somatic reflexes involve skeletal muscle contraction (voluntary - like knee - jerk), while autonomic reflexes involve smooth/cardiac muscle or glandular secretions (involuntary - like digestion regulation).
• Question 19: Sympathetic preganglionic fibers synapse with multiple postganglionic fibers (divergence), allowing widespread effects. For example, during "fight - or - flight", many organs are simultaneously affected (increased heart rate, dilated pupils etc.).

Answer:

• Question 18: A somatic reflex is caused by contraction of skeletal muscles, whereas an autonomic reflex consists of contraction of smooth or cardiac muscle or secretions of glands.
• Question 19: preganglionic fibers synapse with several postsynaptic fibers.