physics and math tutor exam Q/A Flashcards
Briefly explain one function of the endocrine system.
To secrete the hormones which are required to regulate many bodily functions to promote appropriate growth or metabolism or reproduction.
Identify two glands that form part of the endocrine system and outline their functions
thyroid gland - releases thyroxine for metabolism and affects growth
pituitary gland - causes other glands to secrete their hormones or directly produces
effects
Outline the role of adrenaline in the fight or flight response.
- Adrenaline is released from the adrenal medulla in response to activation of the sympathomedullary pathway
- Adrenaline has a range of effects on the body - increase heart rate, increases respiration and sweating
- The general effects of adrenaline
– prepare the body for action, fight or flight,
– increase blood supply/oxygen, to skeletal muscle for physical action – increase oxygen to brain for rapid response planning
You are walking home at night. It is dark and you hear someone running behind you. Your breathing quickens, your mouth dries and your heart pounds. Then you hear your friend call out, “Hey, wait for me! We can walk back together.” Your breathing slows down and after a couple of minutes you are walking home calmly with your friend.
Explain the actions of the autonomic nervous system. Refer to the description above in your answer.
A01 - one section of the autonomic nervous system (sympathetic nervous system) responds to a perceived threat / it produces physiological changes that prepare the body for fight or flight (the alarm response)
the other section (parasympathetic nervous system) restores normal physiological functioning when the threat has passed
A02- sympathetic activity – breathing quickens, mouth dries, heart pounds parasympathetic – breathing slows down / becoming calm.
The fight or flight response enabled our ancestors to survive but can be less helpful in response to more modern stressors.
Explain how the body responds during fight or flight and why this could be unhelpful in a driving test situation.
the fight or flight response causes adrenaline to be released which can cause an increased production of sweat and faster heart and breathing rate which could be off putting and unhelpful during a driving test (e.g. sweaty hands may make it harder to grip the steering wheel).
the fight or flight response enables a quick reaction to fight the threat or run away from it but neither of these options would be helpful in a driving test as if you ran away or attacked the instructor you would fail the test.
Information can only travel in one direction at a synapse.
Explain why neurons can only transmit information in one direction at a synapse.
- the synaptic vesicles containing the neurotransmitter are only present on / released from the presynaptic membrane
- the receptors for the neurotransmitters are only present on the postsynaptic membrane
- it is the binding of the neurotransmitter to the receptor which enables the signal / information to be passed / transmitted on (to the next neuron)
- diffusion of the neurotransmitters mean they can only go from high to low concentration, so can only travel from the presynaptic to the postsynaptic membrane.
Martha was telling her friend Sanya about her recent frightening experience.
’I was walking home by myself in the dark. Suddenly, I heard footsteps behind me and I realised that someone was getting closer to me. I saw a bus at the bus stop and decided to run. I don’t think I have ever moved with such speed. I leapt on the bus – shaking, sweating and my heart was beating so fast I nearly collapsed.’
Outline the role of the central nervous system and autonomic nervous system in behaviour. Refer to Martha’s frightening experience in your answer.
CNS - controls reflex behaviours
ANS - prepares body for action; parasympathetic division conserves
Likely answers for CNS:
cerebral cortex in higher mental functions (I realised that…); decision making (…I decided to run.) temporal lobe in processing auditory information (… I heard footsteps behind me…); occipital lobe in processing visual information (I saw a bus…).
Likely answers for ANS will relate to the sympathetic division of ANS and to fight / flight response: increased heart rate in emergency action (…my heart was beating so fast…);
increased action of adrenal glands and energising effect (…moved with such speed / shaking) blood vessels to limbs dilate (… sweating).
Jeremy is digging in the garden. He feels the spade hit a rock and stops digging immediately.
Explain how sensory, relay and motor neurons would function in this situation.
Sensory neurons send information from the senses to the brain – here receptors in Jeremy’s hand would sense the jolt of the spade hitting the rock and send that information via the peripheral nervous system to his brain/CNS.
- Relay neurons connect with other neurons, mostly found in the brain/CNS - here they would be involved in analysis of the sensation, what it means, deciding about how to respond to it, thus acting between the sensory and motor neurons.
- Motor neurons send messages via long axons from the brain to the muscles or effectors – here the message from the brain instructs Jeremy’s arm muscles to stop working and stop the digging action.
Raoul has recently been prescribed a drug for a mental illness. He looks on the internet to find out more about the drug but he does not understand the phrase ‘synaptic transmission’.
Write a brief explanation of synaptic transmission in the brain to help Raoul understand how his drug might work.
Transmission involves impulses crossing a space or gap between an axon terminus and the adjacent neuron (the synapse/synaptic cleft)
Neurotransmitters are chemicals released from vesicles on the presynaptic neuron
They travel/diffuse across the synapse and lock onto receptor sites on receiving/postsynaptic neuron
Some neurotransmitters increase the rate of firing in the receiving neurons and others decrease the rate of firing
Psychoactive drugs work by affecting (increasing or inhibiting) the transmission of neurotransmitters across the synapse
Briefly evaluate the use of EEGs as a way of identifying cortical specialisation in the brain.
safe way of measuring brain activity; there is no surgery or invasive process; helps to identify activity in various regions of brain; its use as a diagnostic tool eg epilepsy; lacks precision in measuring individual action potential of neurons / electrodes not sensitive enough
The electroencephalogram (EEG) and event-related potentials (ERPs) both involve recording the electrical activity of the brain.
Outline one difference between the EEG and ERPs.
EEG is a recording of general brain activity usually linked to states such as sleep and arousal, whilst ERPs are elicited by specific stimuli presented to the participant.
Briefly evaluate research using split brain patients to investigate hemispheric lateralisation of function.
- the disconnection between the hemispheres was greater in some patients than others
- some patients had experienced drug therapy for much longer than others
- the comparison groups were not considered to be valid as they were often
people with no history of epileptic seizures - the data were artificially produced as in real life a severed corpus callosum can be compensated for by the unrestricted use of two eyes
Josie is twelve. Last year she was involved in a serious road accident and suffered head injuries that caused problems with speech and understanding language. Now, a year later, Josie has recovered most of her language abilities.
Using your knowledge of plasticity and functional recovery of the brain after trauma, explain Josie’s recovery.
- When the brain is still maturing recovery from trauma is more likely. Josie is young.
- Transfer of functions to undamaged areas (‘neural reorganisation’) which can explain her recovery.
- Growth of new neurons and/or connections to compensate for damaged areas (‘neural regeneration’) which can explain her recovery.
- Plasticity allows the brain to cope better with ‘indirect’ effects of brain damage eg swelling, haemorrhage following road accident.
Lotta’s grandmother suffered a stroke to the left hemisphere, damaging Broca’s area and the motor cortex.
(a) Using your knowledge of the functions of Broca’s area and the motor cortex, describe the problems that Lotta’s grandmother is likely to experience.
- as a consequence of damage to Broca’s area, Lotta’s grandmother is likely to suffer from language/speech problems (Broca’s aphasia)
- it will affect her language production (but not her understanding)
- Lotta’s grandmother will only be able to talk in short meaningful sentences which take great effort
as a consequence of damage to the motor cortex,
. Lotta’s grandmother is likely
to suffer from loss of muscle function/paralysis - motor impairments on the right side of the body
Lotta’s grandmother suffered a stroke to the left hemisphere, damaging Broca’s area and the motor cortex.
(b) Lotta worries that because of her grandmother’s age she will not be able to make any recovery.Using your knowledge of plasticity and functional recovery of the brain after trauma, explain why Lotta might be wrong.
- Lotta’s grandmother might still be capable of functional reorganisation/plasticity
- functional compensation by other undamaged areas
- although she is older her brain might still be able to form new connections
(axons and dendrites) between neurons - neuronal loss may be compensated for by regeneration (axon sprouting)
Give one difference between the autonomic nervous system and the somatic nervous
system.
the autonomic nervous system is involuntary whereas the somatic nervous system is under
conscious control.
ANS controls smooth muscles and glands whereas the SNS controls skeletal muscles.
The fight or flight response enabled our ancestors to survive but can be less helpful in response to more modern stressors.
Explain how the body responds during fight or flight and why this could be unhelpful in a
driving test situation.
the fight or flight response causes adrenaline to be released which can cause an increased production of sweat and faster heart and breathing rate which could be off putting and unhelpful during a driving test (e.g. sweaty hands may make it harder to grip the steering wheel).
the fight or flight response enable a quick reaction to fight the threat or run away from it but neither of these options would be helpful in a driving test as if you ran away or attacked the instructor you would fail the test.
