Homeostasis and Response Flashcards
1
Q
Define Homeostasis
A
maintenance of a constant internal environment
- maintains optimum temperature for enzyme action and cell function
2
Q
what does homeoestasis control in the human body?
A
- blood glucose concentrations
- body temperature
- water levels
3
Q
What 3 things are present in nervous and hormonal control systems?
A
- receptors - cells that detect stimuli
2. coordination centres - process the info received from the receptor
4
Q
process of a nervous response:
A
- recpetor cells convert stimulus into electrical impulses
- this electrical impulse travels along sensory neurones to the central nervous system CNS
- at CNS this info is processed and a response is coordinated - an electrical impulse is sent along motor neurone to effector
- effectors eg, muscle, glands, carry out the response
5
Q
CNS consists of:
A
- brain
- spinal chord
6
Q
process of a refex arc
A
- stimulus is detected by a receptor
- impulses sent across sensory neuron
- in CNS impluse passes to a relay neuron
- impulses sent along motor neurone
- Impulses reach effector
7
Q
examples of reflex arc
A
- pupils constricting in bright light
- moving hand off a hot surface
8
Q
Process of electrical transmission at synapse
A
- impulse reaches the end of the first neuron + chemical is released into the synapse
- this chemical diffuses across the synapse
- chemical reaches the second neuron, it triggers the impulse to begin again in the next neuron
9
Q
what is reaction time
A
how long it takes you to respond to a stimulus
- ruler drop test
10
Q
3 regions of the brain and their function
A
- cerebral cortext: controls consciousness, intelligence, memory a language - outer part of the brain
- cerebellum: control fine movement of muscle - rounded structure towards the bottom/back of brain
- Medulla: controls unconscious actions such as breathing and heart rate - brain stem in front of the cerebellum
