Cells A1 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What’s the difference between a eukaryotic and prokaryotic cell?
(give examples of both)

A
  1. eukaryotes have a nucleus (plants, algae, animal, protozoan, fungi)
  2. prokaryotes do not have a nucleus (bacteria, blue-green algae, archaea)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the function of the ribosomes?

A

protein synthesis (70s and 80s)

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

What is the function of nucleus?

A
  1. contains DNA
  2. controls cell activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the function of the mitochondria?

A
  1. site of respiration (folder to form cristae)
  2. ATP production (matrix is its cytoplasm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of smooth endoplasmic reticulum?

A

site of lipid synthesis

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

What is the function of rough endoplasmic reticulum?

A
  1. encrusted in ribosomes
  2. site of protein synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the function of Golgi apparatus?

A
  1. modifies/packages/sorts proteins
  2. modifies/processes triglycerides
  3. combines triglycerides with proteins
  4. packages for release/forms vesicles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the cell surface membrane?

A
  1. made of phospholipid bilayer
  2. controls what enters the cell/is selectively permeable
  3. can be folded to increase surface area
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of lysosomes?

A
  1. contains digestive enzymes
  2. digests worn out organelles (autolysis) (phagocytes contain them)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Function of chloroplasts?

A
  1. contain thylakoids, staked into granum
  2. site of photosynthesis
  3. traps light energy and converts it to chemical energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Function of capsule?

A
  1. protects from immune system
  2. aids bacteria sticking together
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Function of plasmid?

A
  1. circular DNA
  2. contains antibiotic resistant genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Function of cell wall?

A
  1. provides structure
  2. stops osmotic lysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of flagellum?

A

allows movement / propulsion

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

Describe the difference between eukaryotic and prokaryotic cells.

A

Eukaryotic cells have:
1. DNA is linear and associated with proteins
2. contains membrane bound organelles eg.(mitochondria, Golgi apparatus, RER, SER, lysosomes)
3. Has nucleus / DNA contained within nuclear membrane
4. contains larger / 80s ribosomes
5. do not have capsule or flagella

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

The structure of a cholera bacterium is different from the structure of an epithelial cell from the small intestine.
Describe how the structure of a cholera bacterium is different.

A
  1. cholera bacterium is prokaryote
  2. does not have nucleus / has free DNA in cytoplasm / has loop of DNA
    3 and 4 any two from:
    - no membrane bound organelles / no mitochondria / no Golgi / no ER
  3. small ribosomes only
    6 and 7 any two from
    - capsule / flagellum / plasmid / cell wall etc
17
Q

Give one advantage of using a SEM rather than a TEM.

A

Thin sections do not need to be prepared / shows surface of specimen / can have 3D images

18
Q

Explain the advantages and limitations of using a TEM to investigate cell structure.

A

advantages:
1. small objects can be seen
2. TEM has a high resolution
3. wavelength of electrons shorter
limitations:
1. cannot look at living cells
2. must be in a vacuum
3. must cut section / thin specimen
4. preparation may create artefact

19
Q

Explain why a solution was made…
- isotonic
- ice cold
- buffered

A

isotonic - prevent osmotic (no net movement of water so organelle does not burst (lysis) or shrivel)
ice cold - reduce / prevent enzyme activity so organelles are not digested/damaged
buffered - maintain constant PH so proteins don’t denature

20
Q

Describe and explain how cell fractionation can be used to isolate mitochondria from a suspension of animal cells.

A

Any 5 from…
1. cell homogenisation to break open cells and release organelles
2. filter to remove large debris/whole cells
3. use isotonic solution to prevent damage of mitochondria/organelles by osmosis
4. keep cold to reduce damage to organelles by enzymes
5. use buffer to maintain PH and prevent protein/enzyme denaturing
6. use differential centrifuge (at lower speed/1000g) to separate nuclei/cell fragments/heavy organelles
7. re-spin supernatant after nuclei pellet removed, at higher speed to get mitochondria pellet at bottom
8. observe pellet with microscope to identify mitochondria

21
Q

List the order of organelles in a cell from densest to least dense, for cell fractionation experiment.

A
  1. nucleus (1st pellet)
  2. mitochondria, chloroplast (2nd pellet)
  3. ribosomes (3rd pellet - least dense)
22
Q

What is homogenisation?

A

breaking apart the tissue/cell to release organelles into solution

23
Q

What are microvilli?

A
  1. finger like projections
  2. which increase SA of a cell membrane
  3. found in the epithelial cells in the small intestine
24
Q

What are centrioles?

A
  1. function in mitosis
  2. from a network of spindle fibres across the cell onto which the chromosomes attach
  3. these fibres pull the chromosomes/chromatids apart
  4. these are ONLY found in animal cells
25
Q

Name the components of a palisade cell ultrastructure.

A

Ribosomes, SER, RER, nucleus, large central vacuole, starch grain, cell wall, cell membrane, Golgi apparatus, chloroplast, vacuole membrane, mitochondrion, cytoplasm

26
Q

Define the term turgid.

A

When a plant is so full of water that it can be used for structural support, due to the cell walls preventing it bursting eg. the stem

27
Q

Name the differences between a plant and animal cell.

A

Plant/Animal cell
1. cellulose cell wall surrounding membrane / no cell wall
2. chloroplasts present / no chloroplasts
3. large central vacuole / no large central vacuole
4. carbohydrates stored as starch / carbohydrates stored as glycogen

28
Q

Describe the function of granum.

A

stack of thylakoid membranes.

29
Q

Describe the function of thylakoid membrane.

A

contains chlorophyll for photosynthesis

30
Q

Describe the function of stroma.

A

fluid filled matrix
some of the photosynthesis reactions occur here

31
Q

Describe the function of starch grains.

A

the energy storage molecule in plants

32
Q

Describe the function of DNA and ribosomes in the chloroplast.

A

chloroplasts have their own DNA and ribosomes to make enzymes needed for photosynthesis

33
Q

What is a bacterial cell wall made of?

A

murein / peptidoglycan

34
Q

What do viruses have and not have compared to prokaryotic cells?

A

do have:
1. RNA
2. capsid (prokaryotes don’t have this)
don’t have:
3. ribosomes
4. organelles

35
Q

One advantage of TEM over SEM?

A
  1. higher resolution
  2. higher (maximum) magnification
    OR
  3. allows internal details (structures within cells) to be seen / cross section to be taken
36
Q

What is the equation to find out actual size?

A

Actual size = image size ÷ magnification

37
Q

What produces ATP in a prokaryotic cell?

A

Mesosomes

38
Q

What is the fungal cell wall made of?

A

Chitin

39
Q

What is a fungul cell wall made of?

A

Chittin