Brainscape's Knowledge GenomeTM

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


See full index

GCSE Science AQA > Biology - Cell Biology > Flashcards

Biology - Cell Biology Flashcards

1
Q

What does a eukaryotic cell have that a prokaryotic cell doesn’t?

A

A nucleus

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

Is a plant cell a prokaryotic cell or eukaryotic cell?

A

Eukaryotic cell

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

Is a bacterium a prokaryotic cell or eukaryotic cell?

A

Prokaryotic cell

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

Where does aerobic respiration take place in a cell?

A

Mitochondria

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

What part of a cell controls what chemicals enter and leave the cell?

A

Cell membrane

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

What part of the cell contains the DNA?

A

Nucleus

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

In what part of the cell do the majority of chemical reactions take place?

A

Cytoplasm

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

Name any structures found in plant cells but not animal cells.

A

Chloroplasts, large central vacuole, cell wall, starch granules

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

What does a ribosome do?

A

Makes proteins

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

What is resolution?

A

How close two points can be but not blur into each other

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

What is magnification?

A

How many times bigger the image is than the original object

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

True or false? Electron microscopes have greater magnification and resolution than light microscopes.

A

True

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

True or false? Electron microscopes can produce colour images.

A

False

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

Which microscope is better for use on live cells, light or electron?

A

Light (cells must be dead in electron microscopes)

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

Why is iodine added to plant cells, and methylene blue added to animal cells, before looking at them under a light microscope?

A

They stain the structures in the cells so they are easier to see

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

How many μm in a mm?

A

1000

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

If a cell has a width of 100μm and is magnified x 200, what is the width of the image in mm?

A

Image size = Magnification x Real size = 200 x 100μm = 20 000 μm.

20 000 μm / 1000 = 20 mm.

Remember: 1000 μm = 1 mm.

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

Which cells in plants are specialised for absorbing water and minerals from the soil?

A

Root hair cells

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

What is the function of a sperm cell?

A

To carry the father’s DNA to the mother’s DNA in the egg to fertilise it

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

What does an xylem cell do?

A

Transports water and minerals from the roots to the leaves

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

How is an xylem cell specialised for its function?

A

It is hollow

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

What does a nerve cell (neurone) do?

A

A nerve cell carries signals from one part of the body to another

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

How is a nerve cell adapted to its function?

A

It is long and has branches at its ends to connect to other nerve cells

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

How many pairs of chromosomes are found in a normal human cell?

A

23 pairs (46 in total)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q 
Which of the following do chromosomes contain?
A) Mitochondria
B) Cytoplasm
C) Genes
D) Amino Acids
A

C) Genes

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

If a cell divides by mitosis, will the two daughter cells be identical to the original cell?

A

Yes

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

If a cell divides by meiosis, will the four daughter cells be identical to the original cell?

A

No

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

Is mitosis used to produce gametes (sex cells)?

A

No

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

State three factors that may affect the size of a bacterial colony

A

e.g. Temperature, nutrients available, competition from other microorganisms

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

If a bacterial cell has a mean division time of 40 minutes, how many cells will it have produced after 200 minutes?

A

200 divide 40 is 5. So it will divide 5 times. 2^5 = 32, so 32 cells will be produced.

31
Q

If a bacterial cell has a mean division time of 20 minutes, how many cells will it have produced after 2 hours?

A

2 hours = 120 minutes. 120 divide 20 is 6. So it will divide 6 times.

2^6 = 64, so 64 cells will be produced.

32
Q

What is an agar plate?

A

A petri dish and a jelly (source of nutrients)

33
Q

What is the zone of inhibition when you add antibiotic discs to an agar plate?

A

The region around each disc where the bacteria are killed off

34
Q

Why are agar plate cultures incubated at a maximum temperature of 25°C in schools?

A

Harmful bacteria are more likely to grow above this temperature

35
Q

Why is it important to sterilise an agar plate before conducting a culturing experiment?

A

So no unwanted microorganisms grow and compete with your culture.

36
Q

What is a stem cell?

A

A cell which can become one of many different types of cell

37
Q

Where can stem cells be found in an adult human?

A

Bone marrow

38
Q

Where can stem cells be found in a plant?

A

Meristem

39
Q

What is a risk of stem cell therapy?

A

Contamination could pass a virus on to the patient

40
Q

Mr Correct is worried about a plant disease that could spread to the crops on his farm. How could he use stem cells to help?

A

Use stem cells to grow crops of identical plants with disease resistance

41
Q

During a heart attack there is damage or death of heart muscle. How can embryonic stem cells help treat a patient after?

A

Embryonic stem cells could develop into heart muscle cells and replace the damaged cells

42
Q

What are the ethical pros and cons to embryonic stem cell therapy?

A

Pros: helping patients. Cons: embryos are human life, so it is wrong to take stem cells from them.

43
Q

What is diffusion?

A

The spreading of particles from an area of high concentration to low concentration

44
Q

True or false? The bigger the concentration gradient, the faster the rate of diffusion.

A

True

45
Q

True or false? The higher the temperature, the faster the rate of diffusion.

A

True

46
Q

True or false? The larger the particle, the faster the rate of diffusion.

A

False

47
Q

True or false? The larger the surface area, the faster the rate of diffusion.

A

True

48
Q

When will diffusion stop?

A

When the particles are evenly spread everywhere

49
Q

Does diffusion require energy input?

A

No – it is a passive process

50
Q

What is osmosis?

A

Diffusion of water from high water concentration to low water concentration across a partially permeable membrane

51
Q

True or false? Oxygen entering the blood from the lungs is an example of osmosis.

A

False – this is diffusion

52
Q

If you put a potato in pure water what will happen to its mass and why?

A

The water concentration is higher outside, so water will diffuse in by osmosis and the mass will increase

53
Q

If you put a potato in a concentrated salt solution what will happen to its mass and why?

A

The water concentration will be lower outside, so water will diffuse out by osmosis and the mass will decrease

54
Q

What is the formula for percentage change in mass?

A

(Final Mass – Original Mass)/Original Mass x 100%

55
Q

What is active transport?

A

The movement of particles from an area of low concentration to high concentration, requiring energy from respiration

56
Q

Why do root hair cells need to use active transport to take in minerals?

A

The root absorbs so many minerals, the concentration is higher in the root than the soil, so it must use active transport to continue absorbing

57
Q

If a cell has to carry out a lot of active transport, which organelle is it likely to contain a lot of?

A

Mitochondria to supply the energy for active transport

58
Q

If an organism gets larger, does its surface area to volume ratio increase or decrease?

A

Decrease

59
Q

Why do single-celled organisms not require lungs to exchange gases with their environment?

A

Their surface area to volume ratio is very large so enough gas can diffuse across their cell membrane

60
Q

a) What is the surface area of a 3cm x 3cm x 3cm cube?
b) What is its volume?
c) Hence, what is the surface area to volume ratio of the 3cm x 3cm x 3cm cube?

A

a) Six sides. Each has area 3 x 3 = 9cm2. So total surface area is 54cm2.
b) 3 x 3 x 3 = 27cm3
c) 54 : 27 (simplifies to 2 : 1)

61
Q

Which two gases are exchanged in a leaf?

A

Oxygen and carbon dioxide

62
Q

What is the function of alveoli?

A

Diffusion of oxygen into the blood and carbon dioxide out

63
Q

How are the alveoli adapted for their function?

A

Thin moist walls, large surface area, good blood supply

64
Q

Coeliac disease can cause the villi in the small intestines to flatten. How might this affect the absorption of digested food into the blood?

A

This would reduce surface area so less digested food gets absorbed.

65
Q

What adaptations does a leaf have to help gas exchange?

A

Stomata (pores), large flat surface, air spaces inside the leaf

66
Q

What does the cell say?

A

The cell says OK.

67
Q

How many cells are produced in mitosis?

A

Two

68
Q

How many cells are produced in meiosis?

A

Four

69
Q

What is the name of a cell produced by meiosis?

A

A gamete

70
Q

What is the male gamete called?

A

Sperm cell

71
Q

What is the female gamete called?

A

Egg cell

72
Q

How many chromosomes does a human gamete have?

A

23

73
Q

Does every gamete contain the same DNA?

A

No they each contain random mixes of the father’s and mother’s chromosomes present in the parent cell.

74
Q

What is the difference between mitosis and meiosis?

A

Mitosis is normal cell division. It produces two identical daughter cells.

Meiosis is cell division to produce four gametes (sex cells), in a two stage process (i.e. cell division occurs twice). Each gamete has half the normal number of cell chromosomes. Each gamete contains different DNA.

GCSE Science AQA (7 decks)

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