Biopsycology

Question 1

Neurons

Answer 1

-carry chemical messages
Include: cell body
Nucleus- contains genetic information
Dendrites- receive signals from other neurons or from sensory receptors
Axon- carries impulses away, covered in fatty layer of myelins sheath to protect and sleep up impulses, has gaps called nodes of ranvier as they form the impulses to jump the ga
Terminal buttons- communicate to next neuron in chain

Question 2

Sensory neuron’s

Answer 2

• found in receptors e,g eyes, ears, tongue and skin
  -carry nerve impulses from PNS to spinal cord and Brian
  -when impulse reaches brain they are translated to sensations such as vision hearing, taste and touch
  -not all sensory neuron’s reach brain some stop at the spinal cord allowing for reflex actions
  -long dendrites and short axons

Question 3

Relay neuron’s

Answer 3

-most common
- only found in the brain and spinal cord
-connect sensory neurons to motor or other relay neuron’s
-short dendrites and short axons

Question 4

Motor neuron’s

Answer 4

-carry messages from CNS to effectors e,g glands and muscles and control muscle movements
-when stimulated they release neurotransmitters that bind to receptors in the muscle and triggers a response which leads to muscle movement
-muscle relaxation is caused by inhibition of the motor neuron
-short dendrites and long axons

Question 5

How neurons function

Answer 5

-stimulus presented( hot candle detected by pain receptors on hand)
-sensory send a message through peripheral nervous system
-reaches spinal cord where its passes to relay
-then passes to motor neuron or sent to brain
-motor neuron carries message to effector like muscle or gland (pulls arm away from candle)

Question 6

Synaptic transmission

Answer 6

-when impulse reaches end of neuron it triggers the release of neurotransmitters from synaptic vesicles
1. Nerve impulses travels down axon down axon of pre synaptic neuron
2. When reaches end of axon chemical messengers called neurotransmitters are released from the vesicles within the pre synaptic neuron
3. These diffuse across the synapse
4. Neurotransmitters bind to receptors on post synaptic neuron
6. Stimulates post synaptic neuron to transmit a nerve impulse down axon to next neuron
7. Neurotransmitters are deactivated by being reabsorbed back to pre synaptic neuron being broken down by enzymes in synapse

Question 7

Excitation

Answer 7

-e,g dopamine causes excitation of the post synaptic neuron by increasing its potivie charge and making it more likely to fire
- if a message is more likely to cause the post synaptic neuron to fire its called an excitatory synapse

Question 8

Inhibition

Answer 8

E.g serotonin causes inhibition in the receiving neuron
- results in the neuron becoming negatively charged and less likely to fire
- if the message is likely to be stopped at the post synaptic neuron its called inhibitory synapse

Question 9

Central Nervous system

Answer 9

Made up of spinal cord and brain.
Brain: physiological processes
Spinal cord: responsible for reflex actions, and relaying information between the brain and rest of the body

Question 10

Peripheral nervous system

Answer 10

-transmits messages to and from the cns
-relay nerve impulses rom CNS to rest of body and from body back to CNS
Split into somatic and autonomic nervous system