Brainscape's Knowledge GenomeTM

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


See full index

bitheolaíocht > B1: cell biology > Flashcards

B1: cell biology Flashcards

1
Q

Give the role of the nucleus.

A

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
2
Q

Give the role of the cytoplasm.

A

A gel-like substance where chemical reactions happen, contains enzymes.

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

Give the role of the cell membrane.

A

Holds the cell together together and controls what goes in and out.

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

Give the role of the mitochondria.

A

Releases energy from aerobic respiration.

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

Give the role of ribosomes

A

Ribosomes are where protein synthesis happens.

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

Give the role of the cell wall.

A

It supports the cell and strengthens it.

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

Give the role of the permanent vacuole.

A

Contains cell sap to keep the cell turgid.

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

Give the role of the chloroplasts.

A

Where photosynthesis occurs.

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

Give the role of the chlorophyll.

A

Absorbs the light needed for photosynthesis.

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

List the subcellular organelles in a bacterial cell.

A
  • Cytoplasm
  • Cell membrane
  • Cell wall (peptidoglycan)
  • Plasmid DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

List the subcellular organelles that are in a plant cell but not an animal cell.

A
  • Cell wall
  • Vacuole
  • Chloroplast
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Give two differences in structure between prokaryotic and eukaryotic cells.

A
  • Prokaryotic cells are smaller
  • Prokaryotic cells don’t have mitochondria, but eukaryotic cells do.
  • Prokaryotic cells don’t have a true ‘nucleus’ but eukaryotic cells do.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define resolution.

A

Resolution is the ability to distinguish between two points.

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

Give the formula for magnification.

A

Magnification = Image size / Actual size. (i = am)

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

Give the method for preparing a microscope slide.

A
  • Add a drop of water to a clean slide.
  • Prepare your sample.
  • Place the sample onto the water on the slide.
  • Add a drop of iodine solution.
  • Place a cover slip on top.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Give the method for using a light microscope to look at your slide.

A
  • Clip the prepared slide onto the stage.
  • Select the lowest-powered objective lens.
  • Use the coarse adjustment knob to move the stage up to just below the objective lens.
  • Look down the eyepiece, and use the coarse adjustment knob to move the stage downwards until it is roughly in focus.
  • Adjust the focus with the fine adjustment knob, until a clear image is visible.
  • Draw observations neatly with a pencil.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define differentiation.

A

Differentiation is the process by which a cell changes to become specialised to complete its job.

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

How are sperm cells specialised for their function? (3)

A
  • It has a long tail (flagellum) and a streamlined head to help it swim to the egg.
  • There are lots of mitochondria in the cell to provide the energy to swim to the egg.
  • It also contains enzymes in the head to digest through the egg’s cell membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How are nerve cells specialised for their function? (3)

A
  • Nerve cells are long and thin, to cover more distance efficiently.
  • They have branched connections at their ends, to connect to other nerve cells and form a network through the body
  • The axon is insulated by a fatty myelin sheath, which increases the speed of the nerve impulses along the neuron.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How are muscle cells specialised for their function?

A
  • They are long, so they have space to contract.
  • They contain lots of mitochondria, to release the energy needed for contraction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How are root hair cells specialised for their function?

A
  • Have a large surface area, to increase the amount of water and mineral ions absorbed.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How are phloem cells specialised for their function?

A
  • Phloem cells are long
  • They are joined end-to-end
  • Phloem cells have very few subcellular structures, so things can flow through them
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How are xylem cells specialised for their function?

A
  • Xylem cells die and their ends break down, so they join end-to-end and water can pass through efficiently.
  • They are hollow, allowing for more water to pass through.
24
Q

What are chromosomes?

A

Chromosomes are coiled-up lengths of DNA molecules.

25
Q

What is the role of the cell cycle?

A

The cell cycle makes new cells, for growth, development and repair.

26
Q

Give, and explain, the three main stages of the cell cycle.

A
  • Growth: the cell grows in size, and increases the number of sub-cellular structures like mitochondria and ribosomes that it contains.
  • DNA replication and mitosis: DNA is duplicated, so that each daughter cell will have a full set of DNA. When the cell is ready to divide, the duplicated DNA lines up along the centre of the cell, and fibres on each half of the cell attach to their respective half of each chromosome. These cell fibres pull the arms of the chromosomes to opposite sides of the cell.
  • Cytokinesis: The cell membrane and cytoplasm pull apart, forming two daughter cells, so that half of the chromosomes end up in one cell, and the other half in the other: each daughter cell ends up with 23 pairs of chromosomes, and are identical to both each other, and the parent cell.
27
Q

State the three/four main stages of the cell cycle.

A
  • Growth
  • DNA replication and mitosis
  • Cytokinesis
28
Q

What is the DNA like in a cell that is not dividing?

A

When a cell is not undergoing mitosis, the DNA is all spread out in long strings.

29
Q

What is the DNA like in a cell that is undergoing mitosis?

A

When a cell is about to divide, the DNA is duplicated and forms x-shaped chromosomes. Then the cell is ready for mitosis, so the chromosomes line up in the centre of the cell and are pulled apart by cell fibres.

30
Q

Explain how mitosis happens.

A

Once a cell’s chromosomes are line up at the centre of the cell, each arm is pulled apart from the other by cell fibres, to opposite ‘poles’ of the cell. Then, membranes form around each of the sets of chromosomes, and these become the nuclei of the daughter cells. Lastly, the cytoplasm and cell membrane divide, and mitosis is complete. The produced daughter cells are identical to both each other and the ‘parent’ cell.

31
Q

What is a stem cell?

A

A stem cell is:
- able to divide by mitosis to form more cells
- able to differentiate into specialised cells.

32
Q

Give three different types of stem cells, and state where they are found.

A
  • Embryonic: found in embryos
  • Adult stem cells: found in bone marrow
  • Plant stem cells: found in meristem tissue
33
Q

Which kinds of cells can embryonic stem cells divide into?

A

Embryonic stem cells can divide into any other kind of cell that we need.

34
Q

Which kinds of cells can adult stem cells divide into?

A

Adult stem cells can only divide into different types of blood cells.

35
Q

Which kinds of cells can plant stem cells divide into?

A

Plant stem cells can divide into any kind of cells or tissues that the plant needs.

36
Q

Give two examples of diseases that could be treated with stem cells, and describe how.

A
  • Diabetes: insulin-producing cells could be made.
  • Paralysis: nerve cells could be made.
37
Q

Give two examples of risks associated with stem cell use.

A
  • Stem cells could be rejected by the patient’s body/
  • Lab-grown stem cells may become contaminated with a virus, which could be passed onto the patient, making them sicker.
38
Q

Give two arguments against stem cell research.

A
  • Much of the research is being carried out by commercial clinics, so reported successes are not subject to peer review.
  • Some people feel it is immoral to experiment on embryonic stem cells, since each one is a potential human life.
39
Q

Define ‘diffusion’.

A

Diffusion is the spreading out of particles from an area of higher concentration to an area of lower concentration.

40
Q

How does concentration gradient and temperature affect rate of diffusion?

A

The bigger the concentration gradient, the faster the rate of diffusion.
The higher the temperature, the faster the rate of diffusion

41
Q

Define ‘osmosis’.

A

Osmosis is the movement of water molecules from an area of higher water concentration to an area of lower water concentration, over a partially permeable membrane.

42
Q

How could a student investigate the effect of sugar solutions on plant tissue?

A
  • Slice a potato into identical cylinders.
  • Collect some beakers with different sugar solutions: one should be pure water, one should be a very concentrated sugar solution, and there should be a few in between as well
  • Measure the mass of each potato cylinder, then leave one cylinder in each beaker for 24 hours.
  • Remove the cylinders from the solutions, then dry them gently with paper towels. Measure their masses again.
  • If the cylinders have taken in water by osmosis, they will have increased in mass. If water has been drawn in, they will have decreased in mass.
  • You can calculate percentage change in mass, and plot graphs.
43
Q

Define active transport.

A

Active transport is the movement of molecules from a region of lower concentration to a region of higher concentration, across a cell membrane, and requiring energy from cellular respiration.

44
Q

Give two examples of uses of active transport.

A
  • In root hair cells, to take in minerals and water from the soil
  • In the gut, allowing nutrients to be taken into the blood, even when the concentration is higher in the blood than the gut.
45
Q

Explain how plants use active transport to survive.

A

Plants require water and mineral ions like magnesium ions and nitrates to survive, however, these exist at a higher concentration inside the plant than out of it. Active transport is used to allow the root hair cells to absorb these nutrients, even though they should move out of the cell if they followed the rules of diffusion. Root hair cells are adapted for this role by having a large surface area, and lots of mitochondria.

46
Q

How does the size of an organism affect its SA:V ratio?

A

The larger an organism, the smaller its surface area is compared to its volume.

47
Q

Why do large organisms require specialised exchange surfaces?

A

Multicellular organisms have a smaller surface area compared to their volume, so not enough substances can diffuse from their outside surface to supply their entire volume, meaning they often require specialised exchange surfaces for efficient diffusion.

48
Q

How are the alveoli specialised to maximise the diffusion of oxygen and carbon dioxide?

A
  • They have a very large surface area
  • A moist lining for dissolving gases.
  • Very thin walls
  • A good blood supply.
49
Q

How are villi adapted to aid absorption of digested food into the blood?

A
  • Millions of tiny projections increase surface area
  • Single layer of surface cells
  • Good blood supply
50
Q

How does the structure of leaves allow for efficient gas exchange?

A
  • The underside of the leaf is covered in small holes called stomata, so carbon dioxide can diffuse in.
  • The flattened shape of the leaf increases the area of its exchange surface, so gas exchange is more effective.
51
Q

Name five subcellular structures that both plant and animal cells have.

A
  • Nucleus
  • Cell membrane
  • Mitochondria
  • Ribosomes
  • Cytoplasm
52
Q

Where is the genetic material found in bacterial cells?

A

Bacterial cell’s plasmid DNA is found loose in the cytoplasm.

53
Q

Where is the genetic material found in plant and animal cells?

A

The nucleus.

54
Q

Which type of organisms are bacteria: prokaryotes or eukaryotes?

A

Prokaryotes

55
Q

Which gives a higher resolution: a light or electron microscope?

A

Electron.

56
Q

What is cell differentiation?

A

Cell differentiation is the process by which cells become specialized to perform specific functions in an organism.

57
Q
A

bitheolaíocht (6 decks)

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