Biopsychology
Notes
Paper 2 - Section B
,Biopsychology
Animals have 2 systems that allow them to gain/respond to info from the environment:
- the nervous system
- the endocrine system
The nervous system
CNS → brain + spinal cord, where complex processing of info is done / decisions are made
PNS → brings info from senses to CNS and transmits info from CNS to muscles and glands
The central nervous system
● Brain - centre of awareness, responsible for complex command / decisions, divided
into 2 hemispheres (the cortex is more developed in humans than animals)
● Spinal cord - extension of brain, transports messages to / from the brain to the PNS.
It’s responsible for reflexes
The peripheral nervous system
Somatic nervous system (SNS): connects CNS to senses
- It receives info from the senses and transmits it to the CNS
- It transmits info from the CNS to direct movement of muscles
It operates on voluntary actions
- The SNS has sensory and motor pathways
- The SNS controls skeletal muscle, movement etc
- SNS carries commands from the motor cortex
Autonomic nervous system (ANS): maintains homeostasis
- Responsible for vital functions such as heartbeat, breathing, digestion
- It transmits info from and to the internal body organs such as the liver and the lungs
It operates automatically / involuntarily
- The ANS is purely motor pathways
- The ANS controls internal organs and glands of the body
- ANS control centres are in the brain stem
Sympathetic nervous system Parasympathetic nervous system
A division of the autonomic nervous system
Responses that help us deal with Once emergency passes it relaxes the
emergencies - ‘Fight or Flight (Freeze)’ system again - ‘Rest and Digest’
Increases HR/BR, dilates pupils, inhibits Decreases HR/BR, constricts pupils
digestion, inhibits saliva production, stimulates digestion, stimulates saliva
contracts Rectum production, relaxes Rectum
, The endocrine system
● Endocrine system - glands which produce hormones (chemical messengers)
● Hormones released in bloodstream to target organs / cells (contain receptors for
specific hormones) to have an effect
● Provides chemical system of communication
Difference between hormones neurotransmitters
System Endocrine System Nervous System
Point of release Glands Neurons
Transport Through blood stream/vessels Across a synapse
Destination Target cells of an organ Receptor site of receiving neuron
Speed of effect Longer effects (few sec - few days) Very fast (a few milliseconds)
Examples Thyroxine, testosterone… Dopamine, serotonin…
Hormone released Description
Gland
Hypothalamus Controls the Stimulates / controls the release of hormones from
pituitary gland the pituitary gland
Pituitary gland AKA master gland Releases hormones that control / stimulate the
release of hormones from other glands
Pineal gland Melatonin Responsible for important biological rhythms
(sleep-wake cycle)
Thyroid Thyroxine Affects cells in the heart (HR↑)
Regulates metabolism
Adrenal gland Adrenaline A (↑HR = ↑ blood to muscles/brain)
(medulla - in) Noradrenaline N(constricts blood vessels = ↓ blood pressure)
Prepare body for the ‘fight or flight’ response
Adrenal gland Cortisol Stimulates the release of glucose - provides body
(cortex - out) with energy, while suppressing immune system
Ovaries (F) Oestrogen Controls regulation of female reproduction,
including the menstrual cycle and pregnancy
Testes (M) Testosterone Responsible for development of male sex
characteristics during puberty
maintain muscle growth / facial hair / deep voice
Notes
Paper 2 - Section B
,Biopsychology
Animals have 2 systems that allow them to gain/respond to info from the environment:
- the nervous system
- the endocrine system
The nervous system
CNS → brain + spinal cord, where complex processing of info is done / decisions are made
PNS → brings info from senses to CNS and transmits info from CNS to muscles and glands
The central nervous system
● Brain - centre of awareness, responsible for complex command / decisions, divided
into 2 hemispheres (the cortex is more developed in humans than animals)
● Spinal cord - extension of brain, transports messages to / from the brain to the PNS.
It’s responsible for reflexes
The peripheral nervous system
Somatic nervous system (SNS): connects CNS to senses
- It receives info from the senses and transmits it to the CNS
- It transmits info from the CNS to direct movement of muscles
It operates on voluntary actions
- The SNS has sensory and motor pathways
- The SNS controls skeletal muscle, movement etc
- SNS carries commands from the motor cortex
Autonomic nervous system (ANS): maintains homeostasis
- Responsible for vital functions such as heartbeat, breathing, digestion
- It transmits info from and to the internal body organs such as the liver and the lungs
It operates automatically / involuntarily
- The ANS is purely motor pathways
- The ANS controls internal organs and glands of the body
- ANS control centres are in the brain stem
Sympathetic nervous system Parasympathetic nervous system
A division of the autonomic nervous system
Responses that help us deal with Once emergency passes it relaxes the
emergencies - ‘Fight or Flight (Freeze)’ system again - ‘Rest and Digest’
Increases HR/BR, dilates pupils, inhibits Decreases HR/BR, constricts pupils
digestion, inhibits saliva production, stimulates digestion, stimulates saliva
contracts Rectum production, relaxes Rectum
, The endocrine system
● Endocrine system - glands which produce hormones (chemical messengers)
● Hormones released in bloodstream to target organs / cells (contain receptors for
specific hormones) to have an effect
● Provides chemical system of communication
Difference between hormones neurotransmitters
System Endocrine System Nervous System
Point of release Glands Neurons
Transport Through blood stream/vessels Across a synapse
Destination Target cells of an organ Receptor site of receiving neuron
Speed of effect Longer effects (few sec - few days) Very fast (a few milliseconds)
Examples Thyroxine, testosterone… Dopamine, serotonin…
Hormone released Description
Gland
Hypothalamus Controls the Stimulates / controls the release of hormones from
pituitary gland the pituitary gland
Pituitary gland AKA master gland Releases hormones that control / stimulate the
release of hormones from other glands
Pineal gland Melatonin Responsible for important biological rhythms
(sleep-wake cycle)
Thyroid Thyroxine Affects cells in the heart (HR↑)
Regulates metabolism
Adrenal gland Adrenaline A (↑HR = ↑ blood to muscles/brain)
(medulla - in) Noradrenaline N(constricts blood vessels = ↓ blood pressure)
Prepare body for the ‘fight or flight’ response
Adrenal gland Cortisol Stimulates the release of glucose - provides body
(cortex - out) with energy, while suppressing immune system
Ovaries (F) Oestrogen Controls regulation of female reproduction,
including the menstrual cycle and pregnancy
Testes (M) Testosterone Responsible for development of male sex
characteristics during puberty
maintain muscle growth / facial hair / deep voice
