Sense Organs ( The Nervous System)

Question 1

What are the names of the control systems that allow organisms to respond?

Answer 1

Specialized cells
The coordination center
Effectors

Question 2

Define stimuli

Answer 2

Changes in the environment

Question 3

What are receptors?

Answer 3

Receptors are specialized cells that detect stimuli

Question 4

What is the coordination center collectively and what is its function?

Answer 4

The coordination center consists of the brain, spinal cord/pancreas which receives and processes information

Question 5

What are effectors?

Answer 5

Effectors are what bring about responses and restore uptimum levels such as poor body temperature and blood glucose levels.

Question 6

Name the five sense organs

Answer 6

The eye, the ear, the nose, the tongue, and the skin

Question 7

At the back of the eye there is a layer of light sensitive cells called retina. What is the function of these cells?

Answer 7

Retina detects light and sends messages to the brain via the optic nerve

Question 8

The ear detects sounds as vibrations they then magnify the sound and send messages to the brain via which nerve?

Answer 8

The auditory nerve

Question 9

The nose is lined with cells that detect different chemicals. Information is then sent to the brain via which nerve?

Answer 9

The olfactory nerve

Question 10

Relating to the senses, what does the tongue do?

Answer 10

The tongue detects chemicals in the food we eat them sends information to the brain

Question 11

The skin is able to detect more than one stimuli because it contains?

Answer 11

It contains receptors that can detect being touched

Question 12

What is the function of the nervous system?

Answer 12

The nervous system helps us to think, plan, and learn from our experiences, react to stimuli, receives information from our sense organs, and it controls all the other systems’ such as keeping body temperature constant.

Question 13

What are the two main parts of the nervous system?

Answer 13

Central nervous system and peripheral nervous system

Question 14

What is the CNS made up of?

Answer 14

The brain and the spinal cord

Question 15

What is the PNS made up of?

Answer 15

Cranial nerves and spinal nerves

Question 16

What is the purpose of the nerves in our body?

Answer 16

The nerves in our body link the sense organs to the brain and spinal cord and they transfer messages to the CNS

Question 17

Define the nervous system

Answer 17

The nervous system is a network of nerve cells and fibers that controls the body’s activities and carry nerve impulses between the different parts of the body.

Question 18

What will happen if the nervous system is damaged?

Answer 18

The ability of the body to function might be fatal. That may cause weakness, feeling numb and also may affect body functions such as digestion, circulation, and urination.

Question 19

How is the CNS protected?

Answer 19

The CNS consists of the brain which is protected by the skull and the spinal cord which is protected by the vertebrae

Question 20

What organs are the nerves outside of the brain (PNS) associated with?

Answer 20

Cranial nerves carry messages to the brain and spinal nerves carry messages to the spinal cord

Question 21

Define the spinal cord

Answer 21

The spinal cord is an extension from the behind the brain that goes all the way down the back of the body, it is protected by the vertebrae

Question 22

Define the brain

Answer 22

The brain is the expanded front part that is in the head and protected by the skull. It is our body’s computer

Question 23

Function of receptors?

Answer 23

To receive stimuli from the environment

Question 24

Function of effectors?

Answer 24

To bring about responses to stimuli

Question 25

Function of sensory neurons?

Answer 25

Conduct impulses from receptors to the CNS

Question 26

Function of motor neurons?

Answer 26

Conduct impulses from CNS to the effectors

Question 27

What are the five parts of the brain

Answer 27

Cerebrum, cerebellum, medulla oblongata, hypothalamus, pituitary gland

Question 28

Define each part of the brain

Answer 28

The cerebrum is the longest and most highly developed part of the forebrain and it controls most physical activities and intelligent action.

The cerebellum is the front part of the hindbrain which coordinates muscle,movement and balance

The medulla oblongata is the posterior part of the brain which controls all reflex actions and involuntary action like heartbeat and breathing rate .

The hypothalamus is the master controller of all unconscious activity and is situated at the base of the brain it controls the autonomic nervous system, pituitary gland, and also temperature regulation.

The pituitary gland is at the base of the brain and controls production of hormones by the endocrine glands.

Question 29

Define reflex arc

Answer 29

The reflex arc is when a sense organ is stimulated and a message passes to the brain or spinal cord along a sensory nerve. The message is then relayed to a motor nerve and an immediate response occurs in a muscle/gland. It is the pathway between the receptor and effector

Question 30

Give some examples of simple reflexes

Answer 30

Blinking
Knee jerk
Pulling your hand away when you touch something hot
Sneezing
Pupil reflex

Question 31

Differentiate between voluntary and involuntary action

Answer 31

Voluntary action is one in which we have. Control over and we choose to do it. An involuntary action is one over which we do not have control over. And it takes place without us haveing to think about it.

Question 32

Differentiate between involuntary action and a reflex action

Answer 32

In involuntary action messages are sent to the brain
Reflex- ,estates are sent to the spinal cord, rapid and automatic response to a stimulus, does not require conscious control

Spinal and cranial reflex