Behavior-the way organisms respond to stimuli (changes in the environment)

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Simple reflex behavior allows an animal to:

  • find food, shelter or a mate
  • escape from predators
  • avoid harmful environments
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Effectors are either glands or muscles that bring about the resonse

Receptors are found in sense organs and are energy changers

The processor co-ordinates the response -brain or spinal cord aka central nervous system

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Behavior responses can be

  • invoulentary
  • voulentary
  • conditional
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3 types of neurones

  • motor(connects CNS to effectors) 0---------<-
  • sensory(connect receptors in sense organs to the CNS) ->----------0------<-
  • Relay(connect sensory and motor systems) 0---<-
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Reflex responses are:

  • invoulentary
  • fast
  • often protective
  • reflex actions are meditated by a ''reflex arc''

for example blinking to protect your eyes

the spine controls all reflexes except from the eyes of which are controlled by the brain.

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Cot death is caused when the baby maintains its fetal reflex which is to lay still so it uses less oxygen for respiration. If this is kept after birth and smething smothers the baby it will stay still and suffocate. After a few months the baby gets a new reflex this time they move their head from side to side when something covers their airways and kick out aswell as push things off of heir mouths.

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You can modify reflexes and condition them for example the scientist Pavlov who was studying digestive enzymes in dogs stomachs learned to ring a bell and then feed teh dogs so when ever they heard the bell they salivated.

                -> barin is made aware. -> sphincter muscle relaxes opening bladder

Stimulus-> Receptor -> CNS(spinal cord) -> effector -> response

         ->CNS (brain) over rides reflex response     ->sphincter remains contracted   -> hold on

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During develpment the interaction betwenn mammals and their environment results in;

Learning as the result of experiance is where certain pathways in the barin will become more likely to transmit implses than others- the connections between them are strenghtened;

This is why some skills may be learnt through repetition; The variety of potential pathways in the brain make it possible for animals to adapt to new situations.

Feral children are evidence of limits to learning a child that has been deprived of socialisation e.g as a result of deliberate abuse, plane crash etc will be unable to learn human language after the age of 7.

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A nerver impulse travels down the neurone leading to the synapse a chemical called seratonin is released via the reuptake channel for seratonin. Seratonin diffuses into the receptor on the neuron and binds. The nerve impulse carries down the neurone and serotonin goes back up the reuptake channels for it to be reused.

Prozac is an anti dipressant that block the reuptake channels so the seratonin cant go back up. This means the person gets more impulses so they feel happier.

Curane is a neurotoxin it stops impulses moving down the second neurone by binding to the receptor. This means impulses cant get to the other side so the erson is paralyzed.

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