Homeostatis and Response Flashcards
Which word means a change in the environment?
Stimulus
Give two examples of effectors
Muscles or glands
Which sense organ has receptors sensitive to light?
The Eye
Which two sense organs has receptors sensitive to chemicals?
The Nose and Tongue
What three conditions are controlled by homeostatis in the body?
Blood glucose concentration
Body temperature
Water levels
What is included in the central nervous system(CNS)?
Brain and spinal cord
A person accidentaly touches a hot pan. Her hand automatically moves away. Describe the structures in a reflex action.
A receptor detects a stimulus.
A sensory neurone transmits impulse to CNS
A relay neurone in the CNS passes the impulse on.
A motor neurone is stimulated.
The motor neurone passes the impulse on to an effector.
Action is taken (the response).
What is the generalised order during a nervous response?
Stimulus –> receptor –> coordinator –> effector –> response –>
Name the three different types of neurones.
Sensory,relay and motor neurones
What moves across the synapse?
A chemical messenger
What is a synapse?
A tiny gap at the junction between two nerve cells.
What three parts are contained in the brain?
Cerebral cortex, cerebellum amd medulla
Describe the three main parts of the brain.
Cerebral cortex- memory and thought
Cerebellum- movement
Medulla- heartbeat and thinking.
What part of the eye controls the amount of light entering it?
Iris
Why does the pupil get smaller?
It is a reflex response and stops damage to the retina.