The functions of the Nervous system are: to the working of and , to collect, process and to information in the . Consists of Nervous System and the Nervous System

The Central Nervous System consists of the the . The brain provides us with . It is divided into hemispheres. It's layer is highly - called the

The spinal cord is responsible for (e.g. Pulling hand away from hot surface). Transfers messages to and from the and the .

The Peripheral Nervous System transmits messages to and from the Nervous System via . Consists of 2 systems - Nervous System and the Nervous System. The first of these controls muscle via and sensory via sensory .

The Autonomic Nervous System is involved in . It is divided into 2 subsystems- the NS and the sympathetic NS. The fight or flight response happens when a is detected, the triggers in the branch of the ANS.

The Sympathetic Nervous System prepares the body to energy for fight or flight. By increasing , slowing and production. The Parasympathetic Nervous System is the state, it energy. It has actions to the Sympathetic NS as these systems are . E.g. It reduces heart rate, increases digestion in the , and saliva production in the

The Endocrine is made up of a of that produce . It's function is to these hormones in order to body functions - e.g. , growth. Hormones are passed through the body through that the receptor . The Endocrine system works alongside the System to control body functions.

The Pituitary gland is the '' as it other glands, them to release . For example, it produces a hormone called - this induces in , so can be used to labour. It is controlled by the

The adrenal within the adrenal releases into the . This causes the necessary changes for the fight or flight response- the response. (Shows how and ANS work together in stressful event).

Neurons are that and send messages and . Sensory neurons- called nerves as they carry messages from receptors in the NS in the NS toward the and in the NS. Found in sensory in the body, such as , tongue.

Motor neurons are called nerves as they carry messages the NS and to such a muscles and . Relay neurons are found in the and . messages from neurons to neurons or other neurons.

Structure of a neuron: cell body/- includes a which contains the of the cell. Dendritea- -like structures that out from the cell and carry messages from neurons. Axon- -like 'arm' that electrical travel down. Myelin sheath- layer that and protects the . Also speeds up of impulses. Nodes of ranvier- gaps that the and speed up transmissions by forcing to 'jump'. Terminal - at the end of the , they with the next neuron.

Each neuron is separated by a gap called a , this includes the synaptic . Signals within neurons are transmitted . Signals between neurons are transmitted by

Synaptic transmission... 1. Impulse travels down the until it reaches the 2. This the release of from the 3. Neurotransmitter is fired into the and binds with on of the synaptic neuron. 4. The will continue to in this way via other

Neurotransmitters can have either an excitatory or inhibitory effect on the next neuron. Excitatory neurotransmitter (e.g. ) increase the charge of the next neuron, and the likelihood of it . Inhibitory neurotransmitter (e.g. ) increase the charge of the neuron and make it likely to .

The knee-jerk reflex... 1. When a such as a hammer hits a knee, this is detected by in the NS, in the NS. 2. This causes a message to be sent via a () neuron towards the in the NS. 3. This message with a relay neuron which it to a () neuron. This then carries the message to an , such as a , which causes the muscle to , hence the knee jerks.