Biopsychology

Question 1

Outline the role of the central nervous system [4 marks]

Answer 1

The central nervous system (CNS) comprises the brain and spinal cord, and has two main functions. These are the control of behaviour and the regulation of the body’s physiological processes. To do this, the brain receives information from the sensory receptors (e.g. in eyes and skin) and sends messages to the body’s muscles and glands. These messages are sent via the spinal cord, a collection of nerve cells that are attached to the brain and run the length of the spinal column.

Question 2

Define the nervous system and describe its functions

Answer 2

The human nervous system is a complex network of nerve cells that carry messages to and from the brain and the spinal cord (CNS) to different parts of the body and so helps all parts of the body to communicate with each other. It has two main functions
* To collect, process and respond to information in the environment
* To co-ordinate the working of different organs and cells in the body

Question 3

CNS
The CNS, comprising of the ______ and ______ ________, has two main functions: the control of __________ and the ________________________________.
Receives information from the ________ _________ in the sense organs via _________ _________.
Sends messages to ________ organs (muscles and glands) via _______ neurons.
Simple reflexes are relayed via the _______________ __________ without the brain involvement

Answer 3

CNS
- The CNS, comprising of the brain and spinal cord, has two main functions: the control of behaviour and the regulation of the body’s physiological processes
- Receives information from the sensory receptors in the sense organs via sensory neurons
- Sends messages to effector organs (muscles and glands) via motor neurons
- Simple reflexes are relayed via the spinal cord without the brain involvement

Question 4

What is the cerebrum

Answer 4

The largest part of the brain – divided into 4 lobes

Question 5

Describe the function of the cerebellum

Answer 5

Controls balance and coordination

Question 6

Describe the function of the brain stem

Answer 6

Regulates autonomic (involuntary) functions like breathing, heart beat and swallowing

Question 7

Describe the function of the frontal lobe

Answer 7

Thought and speech production

Question 8

Describe the Peripheral Nervous System. Give the divisions of the PNS and breifly describe their function.

Answer 8

Peripheral nervous system
- All the nerves outside the CNS make up the peripheral nervous system. The PNS transmits messages via millions of neurons (nerve cells) to and from the central nervous system.
Divisions of the peripheral nervous system
1. Somatic nervous system - made up of sensory and motor neurons, controls skeletal muscles
1. Autonomic nervous system (ANS) - controls involuntary (autonomic) bodily functions such as heartbeat and digestion. The ANS has 2 parts - sympathetic nervous system (moblilizes) and parasympathetic nervous system (calming).

Question 9

Identify the two divisions of the autonomic nervous system [2 marks]

Answer 9

The sympathetic nervous system and the parasympathetic nervous system.

Question 10

Peripheral nervous system
All the nerves outside the CNS make up the __________ _______ _______. The PNS transmits messages via millions of _______ (nerve cells) to and from the _______ _______ _________.
Divisions of the peripheral nervous system
_________ N________ S________ - made up of ________ and ________ neurons, controls _________ muscles
_________ ________ _______ – controls involuntary (_________) bodily functions such as heartbeat and digestion. The ANS has 2 parts - ___________ (mobilises) nervous system and ___________ (calming) nervous system.

Answer 10

Peripheral nervous system
All the nerves outside the CNS make up the peripheral nervous system. The PNS transmits messages via millions of neurons (nerve cells) to and from the central nervous system.
Divisions of the peripheral nervous system
Somatic nervous system - made up of sensory and motor neurons, controls skeletal muscles
Autonomic nervous system – controls involuntary (autonomic) bodily functions such as heartbeat and digestion. The ANS has 2 parts - sympathetic (mobilises) nervous system and parasympathetic (calming) nervous system.

Question 11

Describe the two divisions of the Autonomic Nervous System

Answer 11

Sympathetic nervous system
- Fight or flight, emergency response
- Uses the neurotransmitter neurodrenaline, which has stimulating effects
- Increases heart rate, constricts blood vessels to increase blood pressure, dilates pupils, slows down non-emergency processes like digestion

The parasympathetic nervous system
- Rest and digest response
- Uses the neurotransmitter acetylcholine, which as inhibiting effects.
- Slows heartbeat, reduces blood pressure, restores digestive processes to normal

Question 12

What is the occipital lobe?

Answer 12

Visual processing

Question 13

What is the function of the temporal lobe?

Answer 13

Auditory processing

Question 14

What is the function of the parietal lobe?

Answer 14

Sensory processing

Question 15

Describe the diencephalon

Answer 15

It acts as a link between the endocrine system and the nervous system. Comprised of the thalamus and hypothalamus.

Question 16

Describe 2 structures that make up the diencephalon.

Answer 16

Thalamus - Acts as a relay station for nerve impulses coming from the senses
Hypothalamus - Responsible for the regulation of body temperature, hunger and thirst

Question 17

Define a neuron

Answer 17

Specialised nerve cells whose function it is to move electrical impulses to and from the central nervous system

Question 18

• Neurons receive a signal via their _________ from other ________ or _______ _________, and pass it on via their ______.
• The _______ is covered in an insulating layer called the __________________, which allows nerve impulses to travel along it more _______
• _________ _________ is segmented by gaps called __________________. These ___________ the transmission of the impulse by forcing it to ‘_______’ across the gaps along the ______.
• The nucleus contains the ____

Answer 18

• Neurons receive a signal via their dendrites from other neurons or sensory receptors, and pass it on via their axon
• The axon is covered in an insulating layer called the myelin sheath, which allows nerve impulses to travel along it more rapidly
• Myelin sheath is segmented by gaps called nodes of Ranvier. These speed up the transmission of the impulse by forcing it to ‘jump’ across the gaps along the axon.
• The nucleus contains the DNA

Question 19

Describe the 3 types of neurons and outline their function

Answer 19

Sensory neurons
- Carry nerve impulses from sensory receptors to the CNS
- Unipolar (only transmit/ send messages)

Relay neurons
- Connect sensory and motor neurons, and are found in the CNS
- Multipolar – send and receive messages

Motor neurons
- Have long axons which carry nerve impulses to muscles, triggering muscle contraction
- Multipolar – send and receive messages

Question 20

Neurons receive a signal via their _________ from other ________ or _______ _________, and pass it on via their ______.
The _______ is covered in an insulating layer called the __________________, which allows nerve impulses to travel along it more _______
_________ _________ is segmented by gaps called __________________. These ___________ the transmission of the impulse by forcing it to ‘_______’ across the gaps along the ______.
The nucleus contains the ____

Answer 20

Neurons receive a signal via their dendrites from other neurons or sensory receptors, and pass it on via their axon
The axon is covered in an insulating layer called the myelin sheath, which allows nerve impulses to travel along it more rapidly
Myelin sheath is segmented by gaps called nodes of Ranvier. These speed up the transmission of the impulse by forcing it to ‘jump’ across the gaps along the axon.
The nucleus contains the DNA

Question 21

Outline one difference between sensory neurons and motor neurons [2 marks]

Answer 21

Sensory neurons only transmit messages, they are unipolar, where as motor neurons are multipolar, they send and receive messages.

Question 22

Outline the structures and processes involved in synaptic transmission [6 marks]

Answer 22

Once an action potential (electrical signal) arrives at the axon terminal of a presynaptic neuron, synaptic vesicles release neurotransmitters that diffuse across the synaptic cleft, where it binds perfectly to specialised receptors that recognize it. Once the neurotransmitter has been taken up by the post-synaptic receptor site i.e. the dendrites of the next neuron, the chemical message is converted back into an electrical impulse and the process of transmission begins again in this other neuron. Postsynaptic effects either excitatory (positivley charged) or inhibitory (negativley charged).

Question 23

Briefly outline how excitation and inhibition are involved in synaptic transmission. [4 marks]

Answer 23

Some neurotransmitters like serotonin act by making the post synaptic neuron more negatively charged so less likely to fire an action potential and thus have an inhibitory post synaptic potential (IPSP). Other neurotransmitters like adrenaline increase the positive charge so make the post synaptic neuron more likely to fire and thus have an excitatory post synaptic potential (EPSP). It stimulates the brain, this is the excitatory effect.
The summation of EPSP and IPSP inputs determines whether or not an action potential is produced, or how frequently the neuron will fire.

Question 24

Outline the structures and processes involved in synaptic transmission [6 marks]
Once _______________ (electrical signal) arrives at the _____ terminal of a ____________________, _________________ release neurotransmitters that diffuses across the _____________, where it binds perfectly to specialised _________ that recognize it. Once the neurotransmitter has been taken up by the _____________________________ i.e. the __________ of the next neuron, the _________ message is converted back into an __________ impulse and the process of transmission begins again in this other neuron. Postsynaptic effects either _________ (negatively charged) or _________ (positively charged).

Answer 24

Outline the structures and processes involved in synaptic transmission [6 marks]
Once action potential (electrical signal) arrives at the axon terminal of a presynaptic neuron, synaptic vesicles release neurotransmitters that diffuses across the synaptic cleft, where it binds perfectly to specialised receptors that recognize it. Once the neurotransmitter has been taken up by the post-synaptic receptor site i.e. the dendrites of the next neuron, the chemical message is converted back into an electrical impulse and the process of transmission begins again in this other neuron. Postsynaptic effects either excitatory (negatively charged) or inhibitory (positively charged).

Question 25

Describe excitatory and inhibitory neurotransmitters, including summation

Answer 25

Excitatory and inhibitory neurotransmitters
Neurotransmitters can have different effects when they bind to the receptor on the post-synaptic neuron.

Excitatory neurotransmitters:
- are positively charged
- cause an excitatory post-synaptic potential (EPSP), making the post synaptic neuron more likely to fire
- include noradrenaline

Inhibitory neurotransmitters:
- are negatively charged
- cause an inhibitory postsynaptic potential (IPSP), making the postsynaptic neuron less likely to fire
- include serotonin and GABA

The summation of EPSP and IPSP inputs determines whether or not an action potential is produced, or how frequently the neuron will fire

Question 26

Breifly describe the function of the autonomic nervous system

Answer 26

Helps transmit and revieve information from organs and glands and governs vital involuntary bodily functions like breathing, digestion stress response. It is comprised of the sympathetic (mobilizing) and parasympathetic (calming) nervous systems.

Question 27

Name 3 glands in the endocrine system and describe the hormones they produce

Answer 27

Pituitary gland
Produces hormones which stimulate other glands to produce other hormones
* Anterior pituitary gland - hormones like Luteinising hormone (LH) and follicle-stimulating hormone (FSH) important in menstral cycle.
* Posterior - releases oxytocin - stimulates contraction of uterus in childbirth, important in mother infant bonding and important role in matinence and repair.
Adrenal gland
* Adrenal cortex - cortisol - regulation of body’s stress response
* Adrenal medula - releases adrenaline & noradrenaline - prepare the body for a fight or flight response.
Sex glands
* Ovaries - oestrogen (puberty) and progestorone (menstrual cycle)
* Testes - testosterone (puberty)

Other glands include: pancreas (digestive enzymes, insulin), Thyroid (thyroxine - metabolism - bone and heart health), hypothalamus (dopamine)

Question 28

Outline the role of one endocrine gland and of one hormone that it produces [4 marks]

(Adrenal gland)

Answer 28

The role of the adrenal gland is to produce cortisol (from the adrenal cortex) and adrenaline and noradrenaline (from the adrenal medulla). Adrenaline helps the body to respond to acute stress by increasing heart rate and blood flow to the muscles and brain, and encouraging the breakdown of glycogen into glucose to provide energy.

Question 29

Identify the neurotransmitter used by the parasympathetic nervous system, which has stimulating effects.

Answer 29

Acetylcholine

Spell - (Ace-tyl-choline)

Question 30

Explain the relationship between endocrine glands and hormones [4 marks]

Answer 30

Endocrine glands produce and secrete hormones. Each gland in the endocrine system produces different hormones that regulate the activity of cells or organs in the body. The timing of a hormone’s release by an endocrine gland is critical for normal functioning, as are the levels of hormone released. Too much or too little at the wrong time can result in dysfunction of bodily systems, as with depression where too little serotonin is released by the pineal, resulting in low mood.

Question 31

The endocrine system works alongside the ________ _________ to control vital functions in the body.
This is a network of ______throughout the body that manufacture and ________ chemical messengers known as __________.
Each gland produces specific hormones

Hormones
___________ messengers which are released by endocrine glands into the ___________ via _______________, where they circulate around the whole body.
Bind to specific __________________ on the surface of ___________, __________ a response in the target cells.

Feedback system
The endocrine system is regulated by feedback to ensure stable concentration of hormones
Both the __________ and ______________ have special receptors that monitor hormone levels
If these rise above normal, they initiate a reduction of the ___________ and ___________ hormones (______&_____)
This slows down secretion of the target gland’s hormone, resulting in the stable concentration of hormones circulating the bloodstream

Answer 31

The endocrine system works alongside the nervous system to control vital functions in the body.
This is a network of glands throughout the body that manufacture and secrete chemical messengers known as hormones
Each gland produces specific hormones

Hormones
Chemical messengers which are released by endocrine glands into the bloodstream via blood vessels, where they circulate around the whole body.
Bind to specific receptor molecules on the surface of target cells, stimulating a response in the target cells.

Feedback system
The endocrine system is regulated by feedback to ensure stable concentration of hormones
Both the hypothalamus and pituitary gland have special receptors that monitor hormone levels
If these rise above normal, they initiate a reduction of the releasing and stimulating hormones (CRH & ACTH)
This slows down secretion of the target gland’s hormone, resulting in the stable concentration of hormones circulating the bloodstream

Question 32

Outline the functions of the endocrine system [6 marks]

Answer 32

The endocrine system is a network of glands throughout the body that manufacture and secrete hormones into the bloodstream. The endocrine system works very closely with the nervous system to regulate the physiological processes of the body. Each gland in the endocrine system produces different hormones, which regulate the activity of the organs and tissues in the body. The endocrine system is regulated by feedback similar to how a thermostat regulates room temperature. For example, as levels of a hormone rise in the bloodstream, secretion of the hormone is reduced. This results in stable concentrations of hormones circulating in the body.

Question 33

Describe the function of the pituitary gland, including hormones it produces

Answer 33

The pituitary gland
* Is controlled by the hypothalamus, just above the pituitary
* It is the ‘master gland’; releasing hormones which control many other endocrine glands
The pituitary has 2 parts:
1. The anterior (front) releases ACTH as a response to stress, and also produces luteinising hormone (LH) and follicle-stimulating hormones (FSH). In females, these stimulate the ovaries to produce oestrogen and progesterone, whereas in males, they stimulate the testes to produce testosterone and sperm
2. The posterior (back) releases oxytocin. In females, oxytocin stimulates contraction of the uterus in childbirth, and is involved in mother-infant bonding. In males, it plays a role in sexual behaviour and a reduction of anxiety.

Question 34

Describe the adrenal glands, including hormones produced

Answer 34

**Adrenal glands **
- Sit on top of the kidneys
- The adrenal cortex – produces cortisol, this regulates important cardiovascular and anti-inflammatory functions in the body. It is also increases in response to stress. Low levels are associated with low blood pressure, poor immune function and an inability to deal with stress.
- The adrenal medulla – releases adrenaline and noradrenaline which prepares the body for fight or flight. Adrenaline increases heart rate and blood flow to the muscles. Noradrenaline constricts the blood vessels causing blood pressure to increase.

Question 35

Outline the fight-or-flight response

Answer 35

The fight-or-flight response is a sequence of activity within the body that is triggered when the body prepares itself for defending or attacking (fight) or running away to safety (flight).
Acute stressors - Sympathomedullary Pathway (SAM)

• Amygdala is mobilised when faced with threat, this signals to hypothalamus, which communicates with the rest of the body through nervous system
• The branch of the ANS called the sympathetic nervous system = arouses the body ready for action.
• SNS sends signals (Neurons carry messages) to the adrenal medulla to direct it to release hormones.
• Adrenal medulla is located above the kidneys and is responsible for the release of the hormone adrenaline and noradrenaline.
• Adrenaline provides the energy needed by the rest of the body in preparation for flight or fight.
• heart to beat faster
• pushing blood to the muscles, heart, and other vital organs
• release of glucose into the blood

Question 36

Evaluate the fight or flight response

Answer 36

Focus on whether the response is adaptive:
- Gender differences - Women have a different response to stress ‘tend and befriend’ – physiological response inhibits flight as release of oxytocin decreases anxiety and fight or flight = Suggests flight fight response may only be applied to males
- Genetic basis for sex differences – SRY gene, promotes aggression and flight or fight response. Is only found on the Y chromosome = Can explain why males are more likely to be aggressive
- Consequences of long term activation of stress response (chronic stressors) can lead to damaged blood vessels, heart disease and suppression of the immune system = Thus not an adaptive response
- Flight or fight doesn’t consider freeze response – Gray – confrontation (freeze) is adaptive for humans to focus attention and look for new information. Adrenaline and cortisol promote this hyper vigilant state, where individual is alert to danger = this gives adaptive advantages as we are able to choose the best response to particular threats.
- Acute stress can led to positive behaviours (greater cooperation during crisis like 9/11 attacks, acute stress can increase friendly behaviour – Von Dawans) = This protective nature has been adaptive in order to survive

Question 37

Give the stages of the SAM pathway

Answer 37

The SAM system
Amygdala
Hypothalamus
ANS
SNS
Adrenal Medulla
Adrenaline