Lesson 1 - The Nervous System

Question 1

What is the nervous system made up of and what does it do?

Answer 1

The central nervous system and the peripheral nervous system. It has 2 roles:

• collect, process and respond to info in the environment
• coordinate the working of different organs and cells in the body

Question 2

What is the central nervous system and it’s function

Answer 2

The central nervous system (CNS) is made of the brain and spinal chord and has two main functions: The control of behaviour, and regulation of the body’s physiological processes. In order to do this the brain must be able to receive information from the sensory receptors and be able to send messages to the muscles and glands of the body in response

Question 3

Structure of the brain

Answer 3

4 main areas:

• Cerebrum: largest part of the brain and has 4 lobes within, each with a different function. The cerebrum is also split into two halves, the left and right hemisphere, responsible for different behaviours
• Cerebellum: responsible for motor skills, balance and coordinating the muscles to allow precise movement
• Diencephalon: contains the thalamus (regulates consciousness, sleep and alertness) and the hypothalamus (regulates body temp, stress response, hunger and thirst)
• Brain stem: Regulates automatic functions like breathing and heart rate

Question 4

Function and structure of the spinal chord?

Answer 4

Function: to relay info between the brain and the rest of the body, allowing the brain to monitor and regulate bodily processes such as digestion and breathing and to coordinate voluntary body movement.

It is connected to different parts of the body by pairs of spinal nerves, which connect to different muscles and glands. If spinal chord is damaged, body areas connected to it by nerves below the damage will be cut off and cease to function

Question 5

What is the PNS?

Answer 5

Is the rest of the nervous system that is not the brain and spinal chord. It transmits messages via neurones to and from the CNS. The PNS is split into two components, the somatic and autonomic nervous system.

Question 6

What is the somatic nervous system?

Answer 6

The somatic nervous system facilitates communication between the CNS and the outside world. It is made of sensory receptors that carry info to the spinal chord and brain, and motor pathways that allow the brain to control movement. Controlled by the motor cortex

Question 7

What is the autonomic nervous system?

Answer 7

The ANS regulates involuntary actions like heartbeat and breathing. It is controlled by the brain stem. It only has motor pathways and it controls smooth muscles and the internal organs and glands of the body. It has 2 components, the sympathetic nervous system and the parasympathetic nervous system. Both regulate same organs but but have opposite effects.

Question 8

What is the sympathetic nervous system?

Answer 8

It is activated when a person is stressed (fight or flight). Heart rate increases and so does breathing. Digestion stops and salivation reduces. Pupils dilate and the flow of blood is directed away from non essential areas like the surface of the skin to the muscles.

Question 9

What is the parasympathetic nervous system

Answer 9

This is activated when the body is relaxing and so conserving energy. Heart rate and breathing reduce, digestion starts, salivation increases and pupils constrict