1. Control and Communication
Part 1 Nervous Control

2. Control and Communication
List the main parts of the nervous system
Draw a motor nerve cell
Identify sensory, relay and motor neurones
Outline the importance of simple arc reflexes

3. The Central Nervous System
Brain
Spinal cord

4. Brain section Cerebrum Hypothalamus Pituitary Cerebellum
Memory, intelligence
Controls the pituitary
Pituitary
Cerebellum
Controls the hormone (endocrine) system
Controls posture and balance
Controls breathing and heart rate
Medulla oblongata

5. Motor Neurone

6. Three types of nerve cells
Motor Neurone (effector)
relay neurone (connector)
Sensory neurone
Motor neurones and sensory neurones are part of the peripheral nervous system

7. Control and Communication
Part 1 Nervous Control

8. Learning objectives
Describe simple reflex arc in terms of sensory, relay and motor neurones, and a reflex action as a means of automatically and rapidly integrating and coordinating stimuli with responses.

9. The three types are connected

10. The reflex arc bypasses the brain
Information reaches the brain after the response (removal of the finger)
This means that the reflex is very quick
The finger is removed quickly before there is further damage to the finger
We can override the reflex arc if we need to move something hot!

11. Reflex arc
NEURON and NEURONE are alternative spellings. They are the same thing!

13. Question
A reflex action is a simple act of behaviour whose function is protective. For example, the eyelid muscle contracts when an object touches the eye. This results in blinking, which helps to prevent damage to the eye. Similarly, when foreign particles such as pepper enter the nasal tract, a sudden contraction of the chest muscles makes the person sneeze and remove unwanted particles from the nose. Although reflex actions are involuntary, some can be partly altered by voluntary means; the person can, to a certain extent, resist blinking or sneezing. Some reflex actions cannot, however, be altered by voluntary means. When food is present in the gut, muscles in the gut wall contract bringing about peristalsis. This muscular movement also ensures efficient digestion by mixing the food thoroughly with digestive enzymes.