Which parts of a nervous reflex arc is usually a muscle or gland?

The given question is incomplete as it does not have the options which are:

a) Sensory receptor

b) Sensory neuron

c) Motor neuron

d) Effector

e) Integration center

The correct answer is option-Effector

Explanation:

A reflex arc is the mechanism of the neurons which controls the reflex action or involuntary responses or the instantaneous responses of the organisms.

The reflex arc involves the sensory receptors, sensory neurons (transmit signals from sense organ to spinal cord), motor neurons (transmit signals from spinal cord to muscle), Integration centre in the spinal cord and effector.

An effector represents the gland or the muscle which receives the transmitted signal from the motor neuron and responds by showing movements.

Thus, option-Effector is the correct answer.

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.