Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

biology year 13 > receptors > Flashcards

receptors Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Explain how the fovea increases the detail of an image

A

• High (visual) acuity
• Each / single cone is connected to a single bipolar/neurone
• Each cone sends separate impulse to the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain how the connection of several rods to a single bipolar cell (Retinal convergence) influences visual acuity

A

• (Spatial) Summation means cannot distinguish between stimuli from different rod cells linked to same bipolar cell;
• Decreases acuity;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Explain how the connection of several rods to a single bipolar cell (Retinal convergence) influences sensitivity

A

• (Summation of) sub-threshold stimuli produces threshold stimulation;
• Increases sensitivity;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

People with red-green colour blindness are unable to distinguish between red and green, and also between other colours

Explain why.

A

• Green sensitive pigment/cones non-functional
OR
Cones that detect green light non-functional;
• Three different types of pigment/cone;
• Other/different colours (‘seen’) due to stimulation of more than one cone/pigment;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain how pressure on the Pacinian corpuscle produces the changes in membrane potential recorded by microelectrode A.

A

• (Pressure) deforms / opens (sodium) channels;
• Sodium ions enter;
• Causing depolarisation;
• Increased pressure opens more channels / greater sodium entry;
• [Size of generator potential determines frequency of action potentials]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Exercise causes an increase in heart rate.

Describe the role of receptors and of the nervous system in this process.

A
  1. Chemoreceptors detect rise in CO2 / H+ / acidity / carbonic acid /f all in pH
    OR
    Baro / pressure receptors detect rise in blood pressure;
  2. Send impulses to cardiac centre/medulla;
  3. More impulses to SAN;
  4. By sympathetic (nervous system for chemoreceptors / CO2)
    OR
    By parasympathetic (nervous system for baro / pressure receptors / blood pressure);
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The rate of ATP consumption of a de-myelinated neurone is greater than that of a myelinated neurone when conducting impulses at the same frequency.

Explain why.

A

• Greater entry of sodium ions / greater exit of K+
• in de-myelinated neurone;
• Ref. to active transport / ref. to ion pumps;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain how nervous control in a human can cause increased cardiac output during exercise.

A

• Coordination via medulla (of brain) / cardiac centre;
• (Increased) impulses along sympathetic nerve;
• To S.A. node;
• Release of noradrenalin;
• More impulses sent from S.A.N (across atria);
• Increased heart rate / increased stroke volume;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain why increased cardiac output is an advantage during exercise.

A

• Higher cardiac output - Increases O2 supply (to muscles);
• Increases glucose supply (to muscles);
• More ATP produced by oxidative phosphorylation / more energy release / more aerobic respiration / actively respiring muscles
• Increases CO2 removal (from muscles) / lactate removal;
• Increases heat removal (from muscles) / for cooling;
• Delays the formation of lactate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe how the Pacinian corpuscle propagates an action potential.

A

• (Pressure causes) membrane/lamellae to become deformed/stretched;
• Sodium ion channels in membrane open and sodium ions move in;
• Depolarisation leading to generator potential;
• Greater pressure more channels open/sodium ions enter;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe what is meant by the term threshold

A

• When threshold has been reached;
• (Threshold or above) causes maximal response / all or nothing principle;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain what happens when pressure is applied to the Pacinian corpuscle (4)

A
  1. Increased pressure deforms stretch-mediated Na+ channel proteins
  2. Na+ channel proteins open and Nat enter
  3. Depolarisation leading to generator potential
  4. Increased pressure opens more stretch-mediated Na+ channel proteins so larger
    generator potential
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where are the rods found? (1)

A

Macula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are the cones found? (1)

A

Fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe how a heartbeat is initiated and coordinated (5)

A
  1. Sinoatrial node sends wave of electrical impulses causing atrial contraction
  2. Non-conducting tissue prevents immediate contraction of ventricles
  3. Atrioventricular node delays impulse whilst blood leaves atria
  4. AVN sends wave of electrical impulses down Bundle of His
  5. Causing ventricles to contract from apex upwards
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain how the heart muscle and the heart valves maintain a one-way flow of blood from the left atrium to the aorta (5)

A
  1. Atrium has higher pressure than ventricle causing atrioventricular valves to open
  2. Ventricle has higher pressure than atrium causing atrioventricular valves to close
  3. Ventricle has higher pressure than aorta causing semilunar valve to open
  4. Higher pressure in aorta than ventricle causing semilunar valve to close
  5. Contraction causes increase in pressure
17
Q

What do Baro-receptors respond to? (1)

A
  1. Changes in blood pressure
18
Q

What do Chemo-receptors respond to? (1)

A
  1. Changes in pH
19
Q

Explain what happens when blood pressure increases above normal (5)

A
  1. Detected by Baroreceptors in walls of aorta and carotid arteries
  2. More frequent impulses sent to medulla oblongata
  3. More frequent impulses from inhibitory centre in medulla to sinoatrial node via parasympathetic nerve
  4. Decreases frequency of impulses from sinoatrial node across atria
  5. Heart rate decreases
20
Q

Explain what happens when blood pressure decreases below normal (5)

A
  1. Detected by Baroreceptors in walls of aorta and carotid arteries
  2. Less frequent impulses sent to medulla oblongata
  3. More frequent impulses from acceleratory centre in medulla to sinoatrial node via sympathetic nerve
  4. Increases frequency of impulses from sinoatrial node across atria
  5. Heart rate increases
21
Q

Explain what happens when blood pH decreases below normal due to increase in
CO2 (5)

A
  1. Detected by chemoreceptors in walls of aorta and carotid arteries
  2. More frequent impulses sent to medulla oblongata
  3. More frequent impulses from acceleratory centre in medulla to sinoatrial node via
    sympathetic nerve
  4. More frequent impulses from sinoatrial node across atria
  5. Heart rate increases
22
Q

Which neurotransmitter is associated with the sympathetic nervous system? (1)

A

Noradrenaline

23
Q

Which neurotransmitter is associated with the parasympathetic nervous system? (1)

A

Acetylcholine

24
Q

Which cardo regulatory centre is linked to the sinoatrial node by the sympathetic nervous system? (1)

A

Acceleratory centre

25
Q

Which cardo regulatory centre is linked to the sinoatrial node by the parasympathetic nervous system? (1)

A

Inhibitory centre

biology year 13 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions