Brainscape's Knowledge GenomeTM

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


See full index

Biology > Topic 1: Cell Biology > Flashcards

Topic 1: Cell Biology Flashcards

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

What do both plant and animal cells have? [5]

A
  1. Nucleus
  2. Cytoplasm
  3. Cell membrane
  4. Mitochondria
  5. Ribosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What extra structures do plant cells have? [3]

A
  1. Cell wall
  2. Permanent vacuole
  3. Chloroplasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What structures do prokaryotic cells have? [5]

A
  1. Cytoplasm
  2. Cell membrane
  3. Cell wall
  4. Circular strand of DNA
  5. Plasmids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do light microscopes from an image?

A

They use light and lenses to form an image and magnify it

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

What do light microscopes allow us to see? [2]

A
  1. Individual cells
  2. Large subcellular structures e.g. nuclei
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do electron microscopes allow us to see more sub-cellular structures? [3]

A
  1. An electron microscope has a much higher magnification and resolving power than a light microscope
  2. This means it can be used to study cells in much finer detail
  3. This allows us to see and understand more sub-cellular structures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the equation for magnification?

A

Magnification = size of image/size of object

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

Define ‘differetiation’

A

Process by which a cell changes to become specialised for its job

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

When does differentiation usually occur in an organism?

A

As it develops

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

When do most animal cells lose the ability to differentiate?

A

At an early stage, after they become specialised

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

Do most plant cells lose the ability to differentiate?

A

No

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

In mature animals, what is differentiation mainly used for?

A

Repairing and replacing cells

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

Name an undifferentiated cell in animals

A

Stem cells

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

Write and check

How is a sperm cell adapted? [3]

A
  1. Long tail and streamlined body - help it swim to the egg
  2. Lots of mitochondria - to provide them with energy from respiration
  3. Digestive enzymes in head - break into the egg cell membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Write and check

How is a nerve cell adapted? [2]

A
  1. Long - cover more distance
  2. Branched connections - connect to other nerve cells and form a network
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Write and check

How is a muscles cell adapted? [2]

A
  1. Long - space to contract
  2. Lots of mitochondria - provides them with the energy they need
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How is a root hair cell adapted? [2]

A
  1. Lots of hairs
  2. Large surface area
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are phloem cells adapted? [1]

A

Very few subcellular structures - allows stuff to flow through

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

How are xylem cells adapted? [1]

A

Hollow - allows stuff to flow through

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

Where are chromosomes found?

A

In the nucleus

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

What are chromosomes made from?

A

DNA molecules

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

What are found on chromosomes?

A

Genes

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

Why do chromosomes normally come in pairs?

A

One copy from the mother and one copy from the father

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

Write and check

Describe the stages of mitosis [5]

A
  1. Growth - the cell grows and increases the amount of subcellular structures it has (mitochondria and ribosomes)
  2. DNA Replication - the cell duplicates its DNA. The DNA is copied and forms x-shaped chromosomes. Each arm is an exact duplicate of the other
  3. Mitosis - the x-shaped chromosomes line up along the centre of the cell and cell fibres pull them apart - the two arms of each chromosome go to opposite sides of the cell
  4. The nucleus divides
  5. Division - the cell membrane and cytoplasm pull apart to form two new daughter cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do multicellular organisms use mitosis for? [3]

A
  1. Growth
  2. Development
  3. Repair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the role of the nucleus?

A

It contains genetic material that controls the activities of the cell

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

What is the role of the cytoplasm?

A

It is a gel-like substance where chemical reactions occur

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

What is the role of the cell membrane?

A

Holds the cell together and controls what goes in and out

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

What is the role of the mitochondria?

A

It is the site of aerobic respiration which releases energy for the cell to use

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

What is the role of ribosomes?

A

Site of protein synthesis

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

What is the role of the cell wall?

A

Supports and strengthens the cell

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

What is the cell wall made from?

A

Cellulose

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

What is the role of the permanent vacuole?

A

Contains a weak salt and sugar solution called cell sap

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

What is the role of chloroplasts?

A

Site of photosynthesis which makes food for the plant

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

What do chloroplasts contain?

A

Chlorophyll

36
Q

What are plasmids?

A

Small rings of DNA

37
Q

What kind of division do prokaryotic cells divide by?

A

Binary fission

38
Q

Write and check

Describe the stages of binary fission [6]

A
  1. The cells grows
  2. The circular DNA and plasmids replicate
  3. Circular DNA strands move to opposite ends of the cell
  4. Cytoplasm begins to divide and new cell wall begins to form
  5. Cytoplasm divides and two new daughter cells are produced
  6. Each daughter cell has one copy of the circular DNA but can have a differing number of plasmids
39
Q

How often can bacteria multiply in the correct conditions?

A

Once every 20 mins

40
Q

In what 2 ways can bacteria be grown?

A
  1. Nutrient broth solution
  2. Colonies on an agar gel plate
41
Q

RP 2: aseptic techniques

Why must petri dishes and culture media be sterilised before use? [2]

A
  1. To kill unwanted microorganisms
  2. To prevent them affecting the results
42
Q

RP 2: aseptic techniques

Why must the inoculating loop be sterilised by passing through a flame? [2]

A
  1. To kill unwanted microorganisms
  2. To prevent them affecting the results
43
Q

RP 2: aseptic techniques

Why must the lid of the petri dish be secured with adhesive tape? [2]

A
  1. To stop the lid falling off
  2. Stop any unwanted microorganisms entering
44
Q

RP 2: aseptic techniques

Why must the petri dish be stored upside down?

A

Stops moisture from dripping down onto the bacteria and disrupting the colonies

45
Q

RP 2: aseptic techniques

In school, why should we not incubate bacteria above 25°C?

A

Reduces the chances that harmful bacteria will grow

46
Q

What is a stem cell?

A

An undifferentiated cell

47
Q

What can embryonic stem cells do?

A

Differentiate into any type of human cell

48
Q

Where are adult stem cells found?

A

Bone marrow

49
Q

What kind of cells can adult stem cells differentiate into?

A

Blood cells

50
Q

Where are stem cells in plants found?

A

Meristems

51
Q

How long can plant stem cells differentiate for?

A

Plant’s entire life

52
Q

What are plant stem cells used for? [2]

A
  1. Rare species can be cloned to protect from extinction
  2. Plant species with special features can be cloned to produce large numbers of identical plants
53
Q

What kind of conditions could embryonic stem cells be used to treat? [2]

A
  1. Diabetes
  2. Paralysis
54
Q

What is therapeutic cloning?

A

An embryo is produced with the same genes as a person. Therefore, stem cells from the embryo are not rejected

55
Q

What is the risk involved with stem cells in medicine?

A

Transfer of viral infections

56
Q

Why are some people against stem cell research?

A

Human embryos shouldn’t be used for experiments since each one has the potential for human life

57
Q

What are the arguments for stem cell research? [2]

A
  1. Curing suffering existing patients is more important than the rights of embryos
  2. The embryos used are unwanted ones from fertility clinics - would otherwise be destroyed
58
Q

Is stem cell research allowed in the UK?

A

Yes, but it has to follow strict guidelines

59
Q

What is diffusion?

A

The net movement of particles from an area of higher concentration to an area of lower concentration

60
Q

How does the concentration gradient affect the rate of diffusion?

A

The bigger the concentration gradient, the higher the rate of diffusion

61
Q

How does temperature affect the rate of diffusion?

A

The higher the temperature, the higher the rate of diffusion

61
Q

How does surface area affect the rate of diffusion?

A

The larger the surface area, the higher the rate of diffusion

62
Q

Which molecules does the cell membrane allow/not allow to diffuse across? [2]

A
  1. Small molecules can diffuse through the membrane (e.g. oxygen, glucose, amino acids and water)
  2. Big molecules can’t diffuse through the membrane (e.g. starch and proteins)
63
Q

What is osmosis?

A

The net movement of particles, across a partially permeable membrane, from an area of higher water concentration to an area of lower water concentration

64
Q

What is active transport?

A

The movement of molecules against their concentration gradient, from an area of lower concentration to an area of higher concentration, across a cell membrane

65
Q

What does active transport require?

A

Energy from respiration

66
Q

How does active transport allow mineral ions to be absorbed by plant roots?

A

It allows roots to absorb minerals from a low concentration in the soil to a high concentration in the plant

67
Q

What are mineral ions needed for in plants?

A

Healthy growth

68
Q

How does active transport allow the blood to absorb sugar molecules?

A

It allows the blood to absorb sugar molecules from a lower concentration in the gut to a higher concentration in the blood

69
Q

What are sugar molecules need for in animals?

A

Cellular respiration

70
Q

What happens to SA:volume ratio as organisms get larger?

A

It decreases

71
Q

Why can small organisms (e.g. bacteria cell) rely on diffusion?

A

They have a large SA:volume ratio so enough substances can be exchanged across the membrane to meet the needs of the organism

72
Q

Why can multicellular organisms not transport substances by diffusion?

A

Their SA:volume ratio is too low

73
Q

What do multicellular organisms have to fix the problem of ineffective diffusion? [2]

A
  1. Exchange surfaces
  2. Transport systems
74
Q

How are exchange surfaces adapted to maximise effectiveness? [4 ways]

A
  1. Thin membranes - short diffusion path
  2. Large SA
  3. Efficient blood supply
  4. Ventilation
75
Q

What is the job of the lungs? [2]

A
  1. To transfer oxygen to the blood
  2. To removed waste CO₂ from the blood
76
Q

What do the lungs contain for gas exchange?

A

Alveoli

77
Q

How are alveoli specialised to maximise diffusion? [4]

A
  1. Big SA
  2. Moist lining - for dissolving gases
  3. Thin walls
  4. Good blood supply
78
Q

What do the small intestines contain for exchange?

A

Villi

79
Q

How are villi specialised to maximise food absorption into the blood? [2]

A
  1. Single layer of surface cells
  2. Good blood supply
80
Q

How are leaves specialised to maximise CO₂ absorption? [2]

A
  1. Large SA
  2. Thin surface
81
Q

How are gills in fish specialised to maximise exchange? [4]

A
  1. Lots of gill filaments - large SA
  2. Gill fillaments covered in lamellae - increases SA further
  3. Lamellae have a good blood supply
  4. Gill filaments have thin surface layer
82
Q

How do you move from millimetres to micrometres?

A

x 1,000

83
Q

How many chromosomes will each nucleus have after undergoing mitosis?

A

The same amount as the parent nucleus

84
Q

In general, why should students repeat their investigation? [2]

A
  1. To check for anomalies
  2. To improve the reliability

Biology (7 decks)

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