nervous system part 2

Question 1

what are the 5 groups of neurotransmitters

Answer 1

acetyl choline
gases - e.g. nitric oxide
amino acids - e.g. glutamate
biogenic amines - synthesised from amino acids e.g. norepinephrine, serotonin
neuropeptides - short chains of amino acids e.g. endorphins

Question 2

name some nervous system disorders

Answer 2

schizophrenia
depression
Alzheimer’s disease
Parkinson’s disease

Question 3

what is Parkinson’s disease

Answer 3

a nervous system disorder that is more common with advancing age
symptoms include difficulty initiating movement, stiffness, muscle tremors, and poor balance
it is caused by death of neurons in the midbrain which normally release dopamine

Question 4

what is a neurotransmitter

Answer 4

a molecule that is released at the synaptic terminal of a neuron at the chemical synapse, diffuses across the synaptic cleft and binds to the postsynaptic cell, triggering a response

Question 5

what is depression

Answer 5

a nervous system disorder characterized by a depressed mood, abnormalities in sleep, appetite and energy levels
there are two types - bipolar disorder and major depressive disorder
results from lack of
it is caused by lack of activity of biogenic amine neurotransmitters
fluoxetine can be used as a treatment - selective serotonin reuptake inhibitor

Question 6

what are SSRIs and what is their role as antidepressants

Answer 6

selective serotonin reuptake inhibitor - they increase the extracellular level of the neurotransmitter serotonin by limiting its reabsorption (reuptake) into the presynaptic cell, increasing the level of serotonin in the synaptic cleft available to bind to the postsynaptic receptor

Question 7

what is the role of dopamine

Answer 7

attention, problem-solving, and memory and enjoyment

Question 8

what is the role of serotonin (biogenic amine)

Answer 8

an inhibitory neurotransmitter, meaning that it doesn’t give the next neuron the signal to fire. Serotonin is involved with mood, as well as your sleep cycle

Question 9

what is the role of GABA (biogenic amine - made from glutamate amino acids)

Answer 9

an inhibitory neurotransmitter that helps to balance any neurons that might be over-firing. helpful with anxiety or fear because the release of GABA helps to calm you down. involved in vision and motor control

Question 10

what is the function of norepinephrine and epinephrine (made from amino acids - biogenic amines)

Answer 10

excitatory neurotransmitter that helps to activate the sympathetic nervous system, which is your “fight or flight” response to a stressor.

Question 11

what do pleasure drugs do to the reward system

Answer 11

they enhance it

Question 12

give examples of pleasure drugs that act on the reward system

Answer 12

cocaine, heroin, amphetamine, alcohol and tobacco

Question 13

do most pleasure drugs affect ore than one neurotransmitter

Answer 13

yes e.g. alcohol affects Dopamine, GABA, endorphin, glutamate…….

Question 14

how does cocaine affect the reward system

Answer 14

it floods the synaptic cleft with dopamine and block removal
the body then responds with negative feedback resulting in
- reduced dopamine release
- reduced receptor density
- reduced metabolism of brain areas
which contribute to withdrawal syndrome

Question 15

what are the cell that have a receptor for a hormone called

Answer 15

target cells

Question 16

which organ system is responsible for chemical signalling by hormones

Answer 16

the endocrine system

Question 17

which 2 organ systems tend to overlap in control of chemical signalling

Answer 17

endocrine and nervous system

Question 18

what are the steps in endocrine signalling

Answer 18

hormones are secreted into extracellular fluid by endocrine cells
the hormones reach the target cells via the bloodstream

Question 19

what are the main functions of endocrine signalling

Answer 19

to maintain homeostasis
to mediate responses to environmental stimuli
regulation of growth and development
triggers physical/behavioural changes underlying sexual maturity and reproduction

Question 20

what are the 3 major chemical classes of hormones

Answer 20

polypeptides
steroids
amines

Question 21

what type of hormone is insulin

Answer 21

polypeptide

Question 22

what type of hormone is cortisol

Answer 22

steroids

Question 23

what type of hormones are epinephrine and thyroxine

Answer 23

amines

Question 24

how do water soluble and lipid soluble hormones differ

Answer 24

location of receptor proteins in target cells:

• water soluble hormones travel freely in the bloodstream
• water soluble hormones can’t diffuse through target cell membranes so the receptors are on the cell surface (they sometimes alter gene transcription)
• lipid soluble hormones bind to transport proteins to keep them soluble in the blood
• lipid soluble hormones diffuse into target cells and bind too receptors in the cytoplasm or nucleus (it changes gene transcription)

Question 25

are thyroxine and steroid hormones water soluble or fat soluble

Answer 25

fat soluble (hydrophobic)

Question 26

are peptide hormones ad neurotransmitters fat soluble or water soluble

Answer 26

water soluble (hydrophilic)

Question 27

what different response can result from a water soluble hormone binding to a cell surface receptor

Answer 27

activation of an enzyme change in uptake/secretion of specific molecules rearrangement of the cytoskeleton receptors can cause proteins to move into the nucleus and alter transcription

Question 28

what is signal transduction

Answer 28

the conversion of an extracellular signal into an intracellular response

Question 29

what is the signal transduction response to short term stress

Answer 29

when in a stressful situation, the adrenal glands on top of the kidneys release epinephrine (adrenaline) epinephrine binds to a G protein coupled receptor in the plasma membrane of target cells this triggers a cascade of reactions involving synthesis of cAMP cAMP activates kinase production which breaks down glycogen and inactivates glycogen synthesis enzymes the liver releases glucose providing the body with extra fuel

Question 30

what is the signal transduction response to steroid hormones

Answer 30

most steroid hormone receptors are in the cytosol binding of a hormone to the receptor forms a complex that moves into the nucleus the receptor part of the complex alters transcription of particular genes

Question 31

some endocrine cells are found in organs that are not part of the endocrine system. give an example

Answer 31

the stomach contains isolated endocrine cells that help regulate digestive processes by secreting the hormone gastrin

Question 32

what are the ductless organs called where endocrine cells are grouped

Answer 32

endocrine glands e.g. thyroid glands

Question 33

what is the difference between endocrine glands and exocrine glands

Answer 33

endocrine glands secrete hormones directly into the surrounding fluid exocrine glands have ducts that carry the secreted substances such as sweat or saliva onto body surfaces or into body cavities

Question 34

name the human endocrine glands

Answer 34

``` thyroid parathyroid adrenal ovaries testes hypothalamus pituitary pancreas ```

Question 35

what are the steps in a simple endocrine pathway (negative feedback)

Answer 35

endocrine cells respond to a stimulus by secreting hormones hormone travels in the blood stream to target cells where it interacts with receptors signal transduction brings about a physiological response e.g. secretin to neutralise chyme

Question 36

what are the steps in a simple neuroendocrine pathway (positive feedback)

Answer 36

stimulus received by a sensory neuron rather than an endocrine tissue the sensory neuron secretes a neurosecretory cell the neurosecretory cell secretes a neurohormone which diffuses into the blood stream and travels to target cells e.g. oxytocin in suckling

Question 37

where are hormones released by the posterior pituitary made

Answer 37

the hypothalamus

Question 38

where are hormones releases by the anterior pituitary made

Answer 38

the anterior pituitary (makes and produces under regulation of the hypothalamus)

Question 39

in negative feedback, the response ……….. the initial stimulus

Answer 39

reduces - it helps restore a pre-existing state

Question 40

in positive feedback, the response ………… the initial stimulus

Answer 40

enhances

Question 41

what are the 2 posterior pituitary hormones

Answer 41

ADH and oxytocin - they are made in the hypothalamus and stored in the posterior pituitary to be realised n response to nerve impulses from the hypothalamus

Question 42

hormones released by the hypothalamus trigger the release of ……………… pituitary hormones

Answer 42

anterior

Question 43

what are the 2 types of stress

Answer 43

rapid - fight or flight | long term - if beyond homeostatic control

Question 44

what are responses to rapid stress

Answer 44

liver breaks down glycogen to supply glucose epinephrine is released into the blood heart beats faster and stronger - blood pressure rises fat cells release fatty acids into the blood blood vessels to gut and skin constrict while more blood flows to the escape muscles

Question 45

………. is produced by the hypothalamus and ………... released by the posterior pituitary in response to long term stress. the adrenal glands then produce ………...

Answer 45

CRH ACTH cortisol

Question 46

what are the actions of cortisol

Answer 46

* Supresses immune response * Increases glucogenesis * Diverts energy to the CNS * Inhibits insulin production

Question 47

what is a circadian cycle

Answer 47

a daily cycle

Question 48

what is chronobiology

Answer 48

systematic study of adaptations to cope with regular geophysical cycles

Question 49

what is chronotype

Answer 49

a person's natural inclination with regard to the times of day when they prefer to sleep or when they are most alert or energetic.

Question 50

if you find it easy to wake up is your circadian rhythm long or short

Answer 50

short

Question 51

if you find it hard to wake up is your circadian rhythm long or short

Answer 51

long

Question 52

what is social jetlag

Answer 52

when the biological clock is out of sync

Question 53

what do body clocks coordinate with

Answer 53

environment keys e.g. sunlight, mealtimes

Question 54

what can an annual or seasonal change in the body clock be a result of

Answer 54

hibernation, aestivation, reproduction, migration