Body Coordination

Nervous system

•CNS and PNS

•Uses tiny cells called NEURONS to carry electrical messages (Nerve impulses)

CNS-Central Nervous System

•Brain and spinal cord

•Processes ALL of the INFORMATION

PNS-Peripheral Nervous System

•Cranial nerves branch from the brain

•Spinal nerves branch out from the spinal cord

•Sends and receives messages to and from the CNS

Neurons

•Cell body- Contains the nucleus

•Dendrites- which branch out and receives messages

•Knobs- Passes messages to the next neuron

•Axon- Sends nerve impulses along the cell

•Myelin Sheath- Ensures the electrical signal doesn't
pass to other neurons

•Synapse- the space between the neurons

•Neurotransmitters: Chemical messages that are sent between neurons

•The synapse also converts the messages into a chemical message (neurotransmitter)

Sensory and motor neurones

•Sensory neurones- carry messages from the sensory organs to the CNS

i.e. Eye, ears, ect…

•Motor neurones- carry messages from the CNS to the effectors that put the messages into effect

i.e. Muscles or glands

The human brain parts:

•Cerebrum: Conscious thoughts and voluntary movement of every body part

Right cerebral hemisphere: Creative & emotional activities

Left cerebral hemisphere: language & logical thinking (maths/reading)

•Cerebellum: Located at the base of the cerebrum and is responsible for coordination and balance

•Brain stem (medulla): connects the spinal cord to the brain and controls breathing, blood pressure and heart rate

•Nervous system and the brain (PNS)

Somatic nervous system: Responsible for collecting information from our senses and body’s movement.

Autonomic nervous system:

Prepares your body to be alert (sympathetic) and to calm down (parasympathetic).

By redirecting blood to and from the certain areas that are likely to be used, muscles and effectors.

Stimulus>Receptors>sensory nerve>hypothalamus>motor nerve> effectors> effect

•Relay and sensory neurons (CNS)

Relay: Reaction to things without our brain sending the message

Sensory: Tells us something has happened(or we detected some stimulus)

The relay neuron in the spinal cord passes the message to a motor neurone to react. Passed back to the brain. Acts as a reflex

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•Words

Neurotransmitters: A chemical substance/message which is released at the end of a nerve fibre by the arrival of a nerve impulse

Sympathetic: nervous system prepares the body to be alert

Parasympathetic: system helps us to calm down

Sensory neurones: Tells us something has happened from the stimulus

Motor neurons: Gives effect from the hypothalamus

Stimulus: Affects that the sensory neurons detects

•Chemical control

Endocrine system parts:

•Endocrine glands: produce hormones that act as chemical messages

•Hypothalamus: receives messages from the body

•Pituitary glands: controls what hormones are produced and how much of each

Our bodies ensure that: we maintain healthy levels of oxygen, water and the temperature

It is called homeostasis

•Some common hormones

Antidiuretic hormone (ADH): Controls amount of water in urine and does this by causing the kidney to absorb water out of it

Glucagon: Opposite of Insulin, adds glucose to the bloodstream

Insulin: Released by the pancreas and removes excess glucose to the bloodstream

Adrenalin: prepares the body to act in emergency, when triggered by the sympathetic nervous system

	Criado por LIllian Pham quase 10 anos atrás

Notes year 9