Term | Definition |
homeostasis | The maintenance of a constant internal environment. |
stimulus | Something that acts on an organism to bring about a change in activity. |
response | An action brought about by an effector. |
receptor | Something which detects a stimulus. |
effector | Something which brings about a response to a stimulus. |
retina | An area of the eye that contains light receptors. |
coordination | The nervous and endocrine system carry out this function. |
reflex | A type of action carried out without thinking. |
neurotransmitter | A chemical substance which transmits a message across a synapse. |
cerebellum | Part of the brain controlling complex muscle movements. |
meninges | Layers of connective tissue which protect the brain. |
interneurons | Nerve cells which transfer information between other neurons. Connect sensory neurons to motor neurons. |
synapses | Small gaps between neurons. |
cerebrum | Part of the brain responsible for complex thoughts. |
motor neurons | Neurons that carry messages from the central nervous system to muscles and glands. |
peripheral nervous system | The part of the nervous system made up of sensory receptors and nerves. |
spinal cord | Together with the brain, this structure makes up the central nervous system. |
sensory neuron | A nerve cell with ending sensitive to environmental stimuli. |
axon | Carries information away from a nerve cell body. |
dendrite | Carries information towards a nerve cell body. |
myelin sheath | Protective layer around the axon of a neuron. |
medulla | Part of the brain which controls breathing and heart beat. |
hormone | A chemical messenger. |
pituatary | The 'master' gland of the endocrine system. |
adrenalin | Known as the 'fight or flight' hormone. |
insulin | A deficiency of this hormone can cause diabetes. |
hypothalamus | Part of the brain which sends messages to the pituitary gland. |
pancreas | Organ that makes insulin. |
testosterone | Major male hormone. |
human growth hormone (HGH) | A deficieny of this hormone is one of the causes of dwarfism. |
amygdala | Part of the brain involved in recognising emotions |
hippocampus | Part of the brain involved in short term memory. |