topic 2 - cells and control Flashcards

1
Q

what type of cell division results in new body cells being produced?

A

mitosis

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

what does diploid mean?

A

2 sets of chromosomes

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

give 3 reasons why mitosis is important

A

growth, repair, asexual reproduction

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

how many daughter cells are produced in mitosis?

A

2 daughter cells

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

what are the 4 stages of mitosis?

A

P - prophase
M - metaphase
A - anaphase
T - telophase

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

what is a chromosome?

A

long continuous thread of DNA - consists of numerous genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

female chromosomes

A

XX

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

male chromosomes

A

XY

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

what are the stages of the cell cycle?

A
  1. growth
  2. copies dna
  3. growth
  4. mitosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what happens in interphase?

A

DNA replicates, cell organelles duplicate

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

what is interphase?

A

phase of cell cycle before mitosis

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

what happens in prophase?

A

nucleus starts to break down and spindle fibres appear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what happens in metaphase?

A

chromosomes line up at the MIDDLE of the cell
spindle fibres attach to centromere (begin to grow)
centrioles move to opposite ends of pole

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

what is anaphase?

A

spindle fibres pull each chromatid to opposite side of the cell (uses energy)
-> called chromosomes again once reach opposite side

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

what happens in telophase?

A

nuclear membrane reforms to form 2 daughter cells
chromosomes condense
spindle fibres fall apart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what happens in cytokinesis?

A

cytoplasm divides
cell surface membrane separates to form 2 new cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is cancer a result of?

A

changes in the cell that lead to uncontrolled cell division forming a tumour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is a plant meristem?

A

region of cells capable of cell division found in roots and shoots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

why do animals cells differentiate and become specialised?

A

so they can adapt to carry out specific roles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is a percentile chart?

A

measure of weight and height to compare people to and see averages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a stem cell?

A

undifferentiated cell that can keep dividing to form more stem cells, or differentiate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are embryonic stem cells?

A

stem cells from embryos that can differentiate into any specialised cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how are red blood cells specialised?

A

-contain haemoglobin to bind to oxygen
-no nucleus - room for haemoglobin
-large surface area - carry more oxygen
-concave shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where are stem cells found?

A

early human embryos or bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the 2 types of stem cells?

A

embryonic and adult stem cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are some benefits of stem cells?

A

largely successful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what are some problems with stem cells?

A

-could divide too rapidly and cause a tumour
-disease transmission rejection by recipient’s immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

define growth

A

increase in size as a result of the size/number of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

how does growth occur in animals?

A

cell division and differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

how does growth occur in plants?

A

cell division, differentiation, and elongation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what does it mean if a child is on the 75th percentile for height?

A

75% of children (of same age) are shorter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what is the function of the nervous system?

A

allow communication between parts of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what are the 2 organs in the central nervous system (CNS)?

A

brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are the 3 main regions of the brain?

A

cerebrum, cerebellum, medulla oblongata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is the role of the cerebrum?

A

language, movement, memory and vision

36
Q

what is the role of the cerebellum?

A

at the back and is responsible for muscle contraction and balance

37
Q

what is the role of the medulla oblongata?

A

base of brain, responsible for reflex/ unconscious actions

38
Q

what type of brain scan uses X-rays and produces an image of brain structure?

A

CT scans

39
Q

what type of brain scan uses radioactive chemicals and produces an image of brain activity?

A

PET scan

40
Q

why is it hard to treat problems in the CNS (such as brain/spinal injures)? (3)

A
  1. neurones don’t repair themselves
  2. parts of CNS hard to access
  3. could result in permanent damage like paralysis
41
Q

what is a stimulus?

A

change in the environment

42
Q

what are some examples of stimuli?

A

light, sound, touch, temperature, chemicals

43
Q

what is a neurone?

A

1 nerve cell

44
Q

what is a nerve?

A

bundles of neurones

45
Q

what is the role of a receptor?

A

to detect a stimulus

46
Q

what is a motor neurone?

A

neurones that carry information from the CNS to the effectors

47
Q

what is a sensory neurone?

A

neurones that carry information from the receptors to relay neurones in the CNS

48
Q

what is a relay neurone?

A

neurones that carry impulses from the sensory to the motor neurones

49
Q

what feature allows impulses to be transmitted fast?

A
  • long axon
  • sensory neurones = myelin sheath
50
Q

what is the function of a myelin sheath?

A

allows nerve transmission to travel faster
- produced by Schwann cells

51
Q

what is a neurotransmitter?

A

substance which transmits impulse from 1 neurone to another

52
Q

what is the axon?

A

main long fibre of the neurone

53
Q

what are dendrites?

A

extensions which extend out from the cell body to connect to other neurons - forms easy network of communication

54
Q

describe a synapse

A

gap/space between axon of one neuron to the dendrite of another - where neurotransmitters (chemicals) pass nerve impulse from 1 neurone to the other

55
Q

what is a stimulus?

A

change in environment that body reacts to

56
Q

describe the path of the reflex arc using parts of the CNS

A

STIMULUS > receptor cells > sensory neurone > relay neurone > motor neurone > effector > RESPONSE

57
Q

what is a reflect response?

A

response that doesn’t require thought

58
Q

what is a dorsal root ganglion?

A

cell bodies of sensory neurones

59
Q

how do neurotransmitters move?

A

by diffusion

60
Q

describe how an impulse is passed across a synapse?

A
  1. impulse arrives at presynaptic neurone
  2. vesicles move toward - and fuse with - presynaptic membrane -> releases neurotransmitters into synaptic cleft
  3. neurotransmitters diffuse across synaptic cleft
  4. nt attach to receptors on postsynaptic membrane
  5. triggers impulse (travels along postsynaptic neurone)
  6. nt recycled or destroyed once impulse is sent
61
Q

what is a reflex arc?

A

pathway of a reflex response

62
Q

what type of receptor is the eye?

A

a sensory receptor

63
Q

what is the function of the cornea?

A

to refract light and bring them together in the eye (front of eye)

64
Q

what is the function of the iris?

A

controls amount of light entering the eye (is a muscle)

65
Q

what is the function of the lens?

A

focuses light rays on the retina

66
Q

what are the 2 types of light receptor cells in the retina?

A

rods and cones

67
Q

what are rods?

A

receptor cells that detect light

68
Q

what are cones?

A

receptor cells that detect colour

69
Q

what is the ciliary muscle?

A

muscle that controls shape of lens

70
Q

what is the sclera?

A

tough wall supporting eye

71
Q

what is the retina?

A

light sensitive inner surface of eye - contains receptors and layers of neurones

72
Q

what is the fovea?

A

part of retina with high density of cones

73
Q

what is the optic nerve?

A

carry impulses from receptors on retina to the brain

74
Q

what is the aqueous humour?

A

clear fluid filling space in front of eye between lens and cornea

75
Q

what is the vitreous humour?

A

transparent jellylike tissue filling eyeball

76
Q

in dim light…

A

circular muscles relax, radial muscles contract

77
Q

in bright light…

A

circular muscles contract, radial muscles relax

78
Q

when object is close to eye…

A

ciliary muscles contract, suspensory ligaments loosen, lens becomes fatter, light refracted more

79
Q

when object is far from the eye…

A

ciliary muscles contract, suspensory ligaments tighten, lens becomes thinner, light refracted less

80
Q

what is myopia?

A

near sightedness - lens is curved more than normal. focal point falls in front of retina

81
Q

how can myopia be treated?

A

concave contact lens, laser eye surgery

82
Q

what is hyperopia?

A

long-sightedness - lens not curved enough, focal point falls behind retina

83
Q

how can hyperopia be treated?

A

convex lens

84
Q

what is colour blindness?

A

poor or lack of function in 1 or more colour cone

85
Q

what is cataracts?

A

clouding of lens of the eye due to build up of proteins

86
Q

how can cataracts be treated?

A

replacing faulty lens with an artificial one