Cell Activity

Question 1

In addition to what most animal cells have, plant cells often have

Answer 1

Chloroplasts,
A permanent vacuole filled with cell sap and
A cell wall made of cellulose, which strengthens the cell

Question 2

Nucleus

Answer 2

Controls the activities of the cell

Question 3

Cytoplasm

Answer 3

In which Most of the chemical reactions take place

Question 4

Cell membrane

Answer 4

Controls the passage of substance into and out of the cell

Question 5

Mitochondria

Answer 5

Where most energy is released in respiration

Question 6

Ribosomes

Answer 6

Where protein synthesis occurs

Question 7

Chloroplasts

Answer 7

Absorb light energy to make food

Question 8

A bacterial cell consists of

Answer 8

A cytoplasm and a membrane surrounded by a cell wall

Question 9

In a bacterial cell…

Answer 9

The genes are not in a distinct nucleus

Some of the genes are located in circular structures called plasmids

Question 10

Yeast is a

Answer 10

Single celled organism

Question 11

Yeast cells have

Answer 11

A nucleus, cytoplasm and a membrane surrounded by a cell wall

Question 12

Diffusion

Answer 12

Is he spreading of the particles of any substance in solution, or particles of a gas, resulting in a net movement from a region where they are of higher concentration to a region with a lower concentration.

Question 13

The greater the difference in concentration

Answer 13

The faster the rate of diffusion

Question 14

Oxygen required for respiration passed through

Answer 14

Cell membranes by diffusion

Question 15

Osmosis

Answer 15

The diffusion of water from a dilute to a more concentrate solution through a partially permeable membrane that allows the passage of water molecules

Question 16

What causes water to move into or out of the cell by osmosis

Answer 16

Differences in the concentration of the solutions indie and outside a cell

Question 17

Hypertonic solution in animal cells

Answer 17

There is a higher concentration of water outside the cell than inside the cell.
Water in by osmosis
Cell will swell and burst

Question 18

Hypertonic solution in plant cells

Answer 18

Higher water concentration outside than in.
Water in by osmosis
The cell doesn’t burst because of the the cell wall.
Turgid

Question 19

Isotonic solution

Answer 19

Water concentration in outside solution is same as inside cell.
Equal numbers of water molecules moving into cell as out of cell

Question 20

Hypotonic solution in animal cells

Answer 20

Higher concentration of water inside the cell than outside.
Water out by osmosis
Cell shrivels and is crennated

Question 21

Hypotonic solution in plant cells

Answer 21

Cytoplasm shrinks, cell membrane detaches from cell wall.

Cell becomes plasmolysed

Question 22

Turgor

Answer 22

The state of a plant cell when the pressure of the cell wall on the cytoplasm cancels out the tendency from water to move in by osmosis, so the cell is rigid

Question 23

Plasmolysis

Answer 23

The state of a plant cell when large amounts of water have moved out by osmosis and the protoplasm shrinks and pulls away from the cell wall leaving visible gaps

Question 24

Active transport

Answer 24

Substances are sometimes absorbed against s concentration gradient. This requires the use of energy from respiration. The process is called active transport

Question 25

Active transport enables plants to

Answer 25

Absorb ions from very dilute solutions, e.g by root hair cells

Question 26

A single celled organism has a relatively …… Surface area to volume ratio

Answer 26

Large

Question 27

Where do all the necessary exchanges occur in a single celled organism

Answer 27

Via its surface membrane

Question 28

The size and complexity of an organism will

Answer 28

Increase the difficulty of exchanging materials

Question 29

The effectiveness of an exchange surface is increased by

Answer 29

Having a large surface area that is thin, to provide a short diffusion path.
(In animals) having an efficient blood supply.
(In animals, for gaseous exchange) being ventilated

Question 30

The small intestine is adapted for the maximum absorption of digested food molecules because

Answer 30

The folded villi greatly increase the surface area of the intestine.
The villi are made of a single layer of thin cells.
Beneath he gillie is an extensive blood capillary network to distribute the absorbed food molecules

Question 31

The lungs are adapted for maximum exchange surface as

Answer 31

The air sacs (alveoli) have a very large large total surface area.
They have a very good blood supply

Question 32

The specialised cells of the roots of a plant (found just beyond the tip of the root) are adapted :

Answer 32

The tube provides a greater surface area across which water and mineral ions can be exchanged.
The root hair cell contains lots of mitochondria, which release energy from glucose during respiration in order to provide the energy needed for active transport.

Question 33

Most animal cells have

Answer 33

A nucleus, cytoplasm, cell membrane, mitochondria and ribosomes

Question 34

How can dissolved substances move in and out of cells

Answer 34

By diffusion