CO-ORDINATION + RESPONSE IN HUMANS Flashcards
1
Q
how do organisms respond to change in the environment
A
- STIMULUS-internal or external change
- RECEPTORS-sense organs
- CO-ORDINATORS-brain
- EFFECTOR-muscle or gland
- RESPONSE-action taken
2
Q
what does HOMEOSTASIS control
A
- TEMPERATURE-too hot (enzymes control things like respiration)
- WATER CONTENT- to much (blood is dilute) to little (blood is constentrated
3
Q
1.STIMULUS-hight temperature
A
- RECEPTORS-skin
- CO-ORDINATORS-brain
- EFFECTORS-sweat gland
- RESPONSE-sweating
4
Q
VASODILATION-hot weather
A
- muscle cells in the arterioles (small ateries) relax
- this causes dilation of blood vessels
* they get wider
* more blood flows through capillaries
* more heat can be lost by radiation
* red skin
5
Q
VASOCONSTRICTION-cold weather
A
- muscle cells in the arterioles (small ateries) contract
- this causes constriction of blood vessels
* they get narrower
* less blood flows through capillaries
* less heat can be lost by radiation
* pale skin
6
Q
sense organs
A
see touch taste hear smell
7
Q
Hormonal system
A
- slow responses
- long-lasting
- GLANDULAR cells that makes hormones
- hormones transported in the blood
8
Q
Nervous system
A
- fast response
- short-lasting
- Nerve cells involved
- electrical impules go along nerves
9
Q
CENTRAL NERVOUS SYSTEM (CNS)
A
made of brain and spinal cord and is linked to sense organsby nerves.
10
Q
3 types of NEURONES
A
SENSORY-take messages from receptors
RELAY-transfere messages from sensory neurons to other nerve cells
MOTOR-take messages from CNS to effectors (e.g muscles or glands)
11
Q
- neurotransmitter diffuses across the synapase
- nerve impules travels along a neurone
- at the end of the neurone vesictes of neurotransmitter join the cell membrane
- neurotransmitter triggers an impules in the next neurone
A
2.
3.
1.
4.
12
Q
role of the neurotransmitters at synapses
A
it makes sure that nerve impules can only travel in one direction along a nerve pathway
13
Q
EYE distant objects
A
- Ciliary muscles relax
- suspensory ligament pulled tight
- lens pulled thin
14
Q
EYE nearby objects
A
- ciliary muscles contact
- suspensory ligaments slackened
- lens allowed to bulge
15
Q
in darkness
A
- pupil gets bigger (dilates)
- circular muscles in the iris relax
- radial muscles in the iris contract
- iris pulls open the pupil
