The Human Nervous System: Structure And Function

Question 1

What does the nervous system do?

Answer 1

The nervous system enables humans to react to their surroundings, and to coordinate their behavior

Question 2

What is a stimulus?

Answer 2

A stimulus is any change in the surroundings

Question 3

What are stimulus detected by?

Answer 3

Receptors - cells that detect a change. Then information passes along cells (neurons) as electrical impulses to the central nervous system (CNS)

Question 4

What is the central nervous system (CNS)?

Answer 4

The CNS is the brain and the spinal cord

Question 5

What does the central nervous system (CNS) do?

Answer 5

Coordinates the response of effectors which may be muscles contracting or gland secreting hormones

Question 6

What is the order of steps that enables humans to react?

Answer 6

stimulus —> receptor —> coordinator —> effector —> response

Question 7

What are the three main types of neurons and their functions?

Answer 7

. Sensory neurons carry impulses from the receptors to the central nervous system (CNS)
. Relay neurons connect the sensory neurons to the motor neurons in the CNS
. Motor neurons carry impulses from the CNS to the effector

Question 8

What is a synapse?

Answer 8

The small gap in between neurons when they are not joined together

Question 9

How is an impulse transferred in between a synapse?

Answer 9

. When an impulse reaches the end of a neuron, a chemical (neurotransmitter) is released across the gap
. The chemical then diffusers across the synapse
. When the chemical reaches the next neuron, this starts another impulse

Question 10

What is a reflex arc?

Answer 10

The path that a reflex action takes

Question 11

What is the pathway of a reflex arc?

Answer 11

receptor —> sensory neuron —> spinal cord —> motor neuron —> effector