K: Coordination & Response Flashcards
Addictive
A substance on which a person can become physically dependent
ADH
Anti-Diuretic Hormone
Adrenaline
A hormone that is secreted when a person is stressed - it increases the heart and pulse rate and blood pressure
Central nervous system
The brain and the spinal chord
CNS
Central Nervous System (brain and spinal chord)
Coma
A state of deep unconsciousness in which a person does not respond to any external stimuli
Dendrites
Branch-like extensions of neurone of nerve cell which receive impulses from other neurons
Dependency
State of being mentally or physically reliant on something, especially a drug
Diabetes
A serious disease in which the body is unable to regulate blood sugar
Effector
Organ which produces the eventual effect in response to a stimulus (e.g. muscles or glands)
Endocrine gland
One of the glands which secrete hormones into the bloodstream
Endocrine system
Bodily system of glands which produce and secrete hormones into the bloodsystem
Feedback loop
Bodily system in which the effect of a hormone’s action or lack of action is fed back into the system, turning production of the hormone off or on
Hormone
Chemical messengers produced in glands and carried by the blood to specific organs in the body
Hyperglycaemia
Greek for ‘too much sugar in the blood’
Hypoglycaemia
Greek for ‘too little sugar in the blood’
Innate behaviour
The automatic response produced by reflex arcs - for example knee jerk reflex, withdrawal reflex, blinking, salivating
Insulin
A hormone which regulates the level of sugar in the blood. It is produced in the Islets of Langerhans, in the Pancreas.
Learnt behaviour
Complex behaviour which is acquired through experience. We don’t all respond in the same way to a specific stimulus - for example some people don’t eat chocolate cake because they have learnt that it makes them ill, even though they like the taste.
Motor
Motor neurones carry messages out of the CNS to effector organs.
Neurone
A nerve cell. It carries an electrical message or impulse when it is stimulates.
Pancreas
Large gland located in the abdomen near the stomach which produces digestive enzymes and the hormone insulin
Receptor
Organ which recognises and responds to stimuli
Reflex action
An involuntary reaction that happens rapidly in response to a stimuli e.g. moving your hand from a flame
Reflex arc
A nerve pathway which produces an automatic response
Refracted
Deflected from a straight path; bent
Relay neurones
These nerve cells carry messages around the CNS
Response
Reaction to a stimulus; the effect produced by an effector organ - for example you salivate when you taste something.
Retina
The inside layer in the eye that is responsive to light
Sense organ
Organ which receives and responds to a stimulus - for example, the eye, ear, taste buds, skin, nose
Sensory
Sensory neurones carry messages from sense organs into the CNS
Stereoscopic vision
Having two eyes side-by-side, each delivering a s lightly different view to the brain. It enables humans to judge distance, depth and speed.
Stimuli
Things that set off a reaction in the nervous system - for example, light, heat, sound, gravity, smell, taste, or temperature. The singular is stimulus.
Synapse
The gap between two neurones across which nerve signals must jump.
Target organs
The organs which hormones take effect upon
Thermoregulation
The process of keeping a constant body temperature
Tropism
Growth or movement towards or away from a stimulus such as light, gravity or moisture.
Vasoconstriction
Narrowing the blood vessels
Vasodilation
Widening of the blood vessels
Voluntary action
An action which is not forced or a reflex
