B1 - Cell Structure And Organisation Flashcards

1
Q

Formula for Magnification

A

Magnification= image size / size of real object

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

Function of cytoplasm?

A

Liquid gel where organisms are suspended and most chemical reactions for life take place.

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

Function of ribosomes?

A

Protein synthesis takes place, making all proteins for the cell

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

Function of mitochondria?

A

Aerobic respiration - releasing energy for the cell.

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

Function of cell membrane?

A

Controls the passage of substances in and out of the cell.

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

Function of chlorophyll?

A

Absorbs light so plant can make food by photosynthesis

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

Eukaryotic?

A

Genetic material is enclosed in a nucleus

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

Prokaryotic?

A

Genetic material is not enclosed in a nucleus.

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

What are plasmids?

A

Small rings of DNA that code for specific features such as antibiotic resistances

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

Bacteria are….

A

Prokaryotic cells

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

Examples of specialised cells?

A

Nerve cells, muscle cells, sperm cells

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

How are nerve cells specialised? (3)

A

• Lots of dendrites that make connections to other cells
• Axons that carry the impulse from one place to another
• Synapses aww adapted to pass the impulse to another cell or between a nerve cell and a muscle cell

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

How are muscle cells specialised? (3)

A

• Contain proteins that slide over each other and make the fibres contract
• Contain many mitochondria to transfer energy needed for chemical reactions to take place
• Store glycogen, which can be broken down and used in cellular respiration by the mitochondria to provide energy needed for the fibres to contract.

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

How are sperm cells specialised?
(4)

A

• Long tail helps it to move
• Middle section is full of mitochondria, which provide energy for the tail
• Large nucleus contains genetic information to be passed on
• Acrosome stores digestive enzymes to break down the outer layers of the egg

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

Specialised plant cells?

A

Root hair cells, photosynthetic calls’ xylem cells and phloem cells

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

How are root hair cells specialised? (3)

A

• Increased surface area for water to move into the cell
• Permanent vacuole that speeds up movement of water by osmosis from the soil across the root hair cell
• Many mitochondria to transfer energy needed for active transport

17
Q

How are photosynthetic cells specialised? (3)

A

• Contain specialised chloroplasts
• Usually positioned in continuous layers in the leaves and outer layers of the stem so they absorb as much light as possible
• Large perm vacuole that keeps them rigid as a result of osmosis - keep the lead spread out to absorb as much light as possible.

18
Q

How are xylem cells specialised? (2)

A

• Alive at first but die and form long hollow tubes to allow water and mineral ions to move easily through them
• Spirals is lignin make them very strong and help them to withstand pressure of water. Also help support phloem.

19
Q

How are phloem cells specialised? (2)

A

• Call walls between the cells break down to form special sieve plates. Allow water carrying dissolved food to move freely
• Supported by companion cells which transfer energy and support them.

20
Q

D. Diffusion

A

The spreading out of the particles of gas of any substance in a solution ( a solute)

21
Q

Net movement of diffusion ?

A

From high to low concentration, down the conc gradient

22
Q

What effects the rate of diffusion?

A

Difference in concentrations, the temperature and the available surface area

23
Q

How do substances such as urea and glucose and gases such as oxygen and carbon dioxide move out and into cells?

A

Diffusion

24
Q

D. Osmosis?

A

The movement of water to dilute a solution across a partially permeable membrane, Down the conc gradient

25
Q

D. Isotonic?

A

The concentration of the solution is the same inside and outside the cell

26
Q

D. Hypertonic?

A

Solution conc is higher OUTSIDE the cell

27
Q

D. Hypotonic

A

Conc of solution is higher INSIDE the cell

28
Q

Why is osmosis important in plants?

A

To maintain turgor ( turgidity )

29
Q

Plasmolysis?

A

When the vacuole and cytoplasm shrink and the cell membrane is pulled away from cell wall

30
Q

D. Active transport?

A

The movement of substances from a dilute solution to a more concentrated solution against the concentration gradient

31
Q

Where does active transport occur? (2)

A

• Small intestine - uptake of sugar
• In the roots (root hair cells)

32
Q

As the object gets bigger…

A

The surface area:volume ration decreases

33
Q

Why do most exchange surfaces usually have a large SA and thin walls?

A

To give a short diffusion distance.

34
Q

Differences between prokaryotes and eukaryotes? (3)

A

pro’s are….
- smaller
- don’t have a nucleus
-may have plasmids