Chapter 1 - Cell Structure and Transport

Question 1

Give an advantage and disadvantage of using an electron microscope.

Answer 1

• Magnifying power up to about x2,000,000

- Quite expensive

Question 2

Give an advantage and disadvantage of using a light microscope.

Answer 2

• Relatively cheap

- Magnifying power of only x2000

Question 3

How do you calculate magnification?

Answer 3

Size of real object

Question 4

How many nanometers are in a micrometer?

Answer 4

• 1000nm

Question 5

How many metres are in a kilometer?

Answer 5

• 1000m

Question 6

Name the five features of an animal cell.

Answer 6

• Nucleus
• Cytoplasm
• Cell membrane
• Mitochondria
• Ribosomes

Question 7

Name 3 extra features found in a plant cell.

Answer 7

• Cell wall
• Chloroplasts
• Permanent vacuole

Question 8

Explain the function of the cell wall.

Answer 8

• The cell wall is made of cellulose and strengthens and supports the cell.

Question 9

State the function of the mitochondria.

Answer 9

• Where aerobic respiration takes place, releasing energy for the cell.

Question 10

Give the function of the permanent vacuole.

Answer 10

• A space in the cytoplasm filled with cell sap. Keeps cells rigid to support the plant.

Question 11

State 2 types of eukaryotic cells.

Answer 11

Animal and plant cells.

Question 12

Give an example of a prokaryotic cell.

Answer 12

Bacteria.

Question 13

Describe the structure of the bacterial cell.

Answer 13

• Cytoplasm and cell membrane surrounded by a cell wall.
• Cell wall doesn’t contain cellulose.
• A single DNA loop in the cytoplasm.

Question 14

Give 3 examples of specialised animal cells.

Answer 14

• Nerve cell
• Sperm cell
• Muscle cell

Question 15

State 3 adaptations of a sperm cell.

Answer 15

• Large nucleus with genetic information to pass on.
• Long tail to swim towards the egg.
• Mitochondria to produce energy to work.

Question 16

Give 4 examples of specialised plant cells.

Answer 16

• Root hair cells
• Photosynthesis cells
• Xylem cells
• Phloem cells

Question 17

Give 3 adaptations of the root hair cell.

Answer 17

• Increased surface area to allow water to move in.
• Large permanent vacuole to speed up movement of water by osmosis across the cell.
• Mitochondria to transfer energy needed for active transport of mineral ions.

Question 18

Give 2 adaptations of the phloem cell.

Answer 18

• Cell walls between cells break down and form sieve plates, which allow water carrying dissolved food to move up and down.
• Mitochondria of companion cells transfer energy to move dissolved food up and down.

Question 19

State the definition of diffusion.

Answer 19

Movement of particles from a high conc. to a low conc. down the conc. gradient.

Question 20

Give 3 factors which affect the rate of diffusion.

Answer 20

• Difference in concentrations
• Temperature
• Surface area

Question 21

Give 4 examples of dissolved substances moving in and out of cells by diffusion.

Answer 21

• Glucose
• Urea
• Co2
• O2

Question 22

Define osmosis

Answer 22

• Movement of particles from a high conc. to a low conc. through a Partially Permeable Membrane.

Question 23

Define dilute.

Answer 23

• Solution containing a high conc. of solvent and a low conc. of solute.

Question 24

Define isotonic.

Answer 24

• When the conc. of solutes in the solution outside the cell is the same as the internal conc. of the cell.

Question 25

Define hypertonic.

Answer 25

• When the conc. of solutes in the solution outside the cell is higher than the internal conc. of the cell.

Question 26

Define hypotonic.

Answer 26

• When the conc. of solutes in the solution outside the cell is lower than the internal conc. of the cell.

Question 27

What is turgor and why is it important?

Answer 27

• When no more water can physically enter the cell.

- Keeps the cell hard and rigid.

Question 28

Define active transport.

Answer 28

• Movement of molecules from a lower conc. to a higher conc. against the conc. gradient.

Question 29

Why is active transport important in root hair cells?

Answer 29

• Allows absorption of mineral ions required for healthy growth.

Question 30

How does active transport function in a cell? [2]

Answer 30

Active transport uses energy released from respiration [1] to transport and provide energy required. [1]