Biology- Cells

Question 1

What does the cell membrane do?

Answer 1

Controls what enters and leaves the cell.

Question 2

What does the cytoplasm do?

Answer 2

Where chemical reactions occur.

Question 3

What does the mitochondria do?

Answer 3

Where chemical reactions for cell respiration takes place.

Question 4

What does the nucleus do?

Answer 4

The control centre of the cell.

Question 5

What does a cellulose cell wall do?

Answer 5

Prevents cell from bursting when taking in water.

Question 6

What does the vacuole do?

Answer 6

Contains Sap which provides support and makes the cell rigid.

Question 7

What do chloroplasts do?

Answer 7

Contains chlorophyll which makes the cell food during photosynthesis.

Question 8

What does DNA do?

Answer 8

It’s in the form of circular chromosomes.

Question 9

Parts of a microscope.

Answer 9

1.Eyepiece Lens
2.Eyepiece
3.Spine
4.Clips
5.Fine 6.Focusing 7.Knob
8.Course Focusing Knob
9.Objective Lens
10.Stage
11.Light Source

Question 10

Prep an onion slide.

Answer 10

1. Peel thin layer of onion
2. Place on microscope slide
3. Add iodine
4. Lower coverslip

Question 11

Prep a cheek slide.

Answer 11

1. Swab Cheek
2. Smear on microscope slide
3. Add methylene blue
4. Lower coverslip

Question 12

Pros of an electron microscope.

Answer 12

1. Better resolution
2. Higher magnification

Question 13

Cons of an electron microscope.

Answer 13

1. Large
2. Needs a special room
3. Complex prep
4. Kills tissue cell
5. Expensive

Question 14

What is diffusion?

Answer 14

The random movement of a substance from an area of high concentration to a lower concentration.

Question 15

What is concentration gradient?

Answer 15

The difference in concentration between high and low areas.

Question 16

Temperature and concentration gradient

Answer 16

Higher the temperature, more kinetic energy of molecules making them move faster & increasing the rate of diffusion.

Question 17

Surface area & concentration gradient

Answer 17

The larger the area over which diffusion takes place the faster diffusion occurs.

Question 18

Palisade Cell

Answer 18

Lots of chloroplasts

Question 19

Ciliated Epithelial Cell

Answer 19

Waft to and fro to remove bacteria from the airway

Question 20

Neurone

Answer 20

Long and thin with many extensions

Question 21

Pros of embryonic stem cells

Answer 21

1.Can form any cell type
2. Grow rapidly
3. Easy to culture

Question 22

Ethical issues

Answer 22

1. Leads to designer babies
2. Use of embryo in this way is considered murder
3. Human rights of embryo are ignored

Question 23

Adult stem cells cons

Answer 23

1. Can only be used for certain cell types
2. Don’t grow as fast
3. Not as easy to culture

Question 24

Medicine

Answer 24

1. Used to treat Parkinson’s disease
2. Build new bone tissue and cartilage
3. Produce new immune cells to fight infection

Question 25

Leukaemia

Answer 25

1.Chemo/radio destroys cancerous blood cells
2. Bone marrow stops producing blood cells
3. Transplant of bone marrow containing healthy stem cells from a matching donor
4. Donors cells multiply and produce healthy blood cells in the patient

Question 26

Risks- leukaemia

Answer 26

1. Chemo/radio destroys white blood cells before transplant leaving patient with no immune system-> prone to infection
2. Stem cells may divide in an uncontrolled way and produce tumours