Control and Coordination
Main Concepts
Control + Coordination- Control + Coordination in body means:-
Nervous(fast, electrical) + Chemical(slow, hormones)
Nervous- It means the nervous system through which the signals
sent from our skin to brain on touching something hot, cold etc.
These signals are sent to brain through the neurons(brain->
muscles quickly).
Chemicals- It contains hormones. Hormones are slow chemical
passengers which send signals to brain through glands(insulin
lowers sugar over hours).
Reflex- These are the actions which happen automatically in our body.
When we touch something which is very hot you don’t think even once
and your fingers get pulled from that hot substance through spinal cord.
This is called reflex action.
Plants- Plants do not have any nervous system. It means they are not
like if you prick a pin on them they get away from you. No nerves—
hormones + tropisms (stem bends to sunlight via auxin).
10 Key Facts
Neuron: Dendrites → Cell body → Axon → Synapse (chemical
signal)
Reflex arc: Receptor → Sensory → Spinal cord → Motor →
Effector
Brain: Cerebrum(thinking), Cerebellum(balance),
Medulla(heart/lungs)
Hormones: Chemical messengers (target specific organs)
Insulin: Pancreas → Lowers blood sugar (Diabetes = no
insulin)
Thyroxine: Thyroid → Metabolism + growth (Iodine needed)
Adrenaline: Emergency (fight/flight – heart rate up)
Plant hormones: Auxin(growth), Gibberellin(stem),
Abscisic(stress close)
Phototropism: Stem towards light (auxin more on shady side)
Main Concepts
Control + Coordination- Control + Coordination in body means:-
Nervous(fast, electrical) + Chemical(slow, hormones)
Nervous- It means the nervous system through which the signals
sent from our skin to brain on touching something hot, cold etc.
These signals are sent to brain through the neurons(brain->
muscles quickly).
Chemicals- It contains hormones. Hormones are slow chemical
passengers which send signals to brain through glands(insulin
lowers sugar over hours).
Reflex- These are the actions which happen automatically in our body.
When we touch something which is very hot you don’t think even once
and your fingers get pulled from that hot substance through spinal cord.
This is called reflex action.
Plants- Plants do not have any nervous system. It means they are not
like if you prick a pin on them they get away from you. No nerves—
hormones + tropisms (stem bends to sunlight via auxin).
10 Key Facts
Neuron: Dendrites → Cell body → Axon → Synapse (chemical
signal)
Reflex arc: Receptor → Sensory → Spinal cord → Motor →
Effector
Brain: Cerebrum(thinking), Cerebellum(balance),
Medulla(heart/lungs)
Hormones: Chemical messengers (target specific organs)
Insulin: Pancreas → Lowers blood sugar (Diabetes = no
insulin)
Thyroxine: Thyroid → Metabolism + growth (Iodine needed)
Adrenaline: Emergency (fight/flight – heart rate up)
Plant hormones: Auxin(growth), Gibberellin(stem),
Abscisic(stress close)
Phototropism: Stem towards light (auxin more on shady side)
