Diffusion in Cells

Recall which of these is the best definition for diffusion.

• The movement of particles from an area of low concentration to an area of high Concentration

• The movement of particles form an area of high concentration to an area of low concentration

• The combination of multiple dye colors in one solution

Answer explanation

To recall is to remember; present remembered ideas, facts or experiences; bring something back into thought, attention or into one’s mind.

 

Diffusion is the movement of particles from an area of high concentration to an area of low concentration. The particles move further away from each other as time goes on.

Predict what could happen if the distance between the cell membrane and the centre of the cell is too large.

• The cell could find alternative forms of energy

• The cell could die

• the center of the cell couldn't get enough energy

• The cell could move to a different part of the body

Answer explanation

This is an understanding question.

 

To predict is to give an expected result of an upcoming action or event; suggest what may happen based on available information.

 

If the distance to the centre of the cell is too large, that part of the cell would not get enough energy. This would lead to the cell dying.

Select which of these things limits how much oxygen and other substances can diffuse into the cell.

• The surface area of the membrane

• the blood type of the person

• the volume of the cell

• ho tall a tall person

Answer explanation

This is an understanding question.

 

To select is to choose in preference to another or others; pick out.

 

The surface area of the cell membrane limits how much oxygen can diffuse into the cell. The larger the surface area, the more oxygen can enter through the membrane.

Select which of these best describes the surface area to volume ratio of a cell.

• How large a cell is relative to how heavy it is

• how much surface area a cell has relative to the amount of space it takes up

• how much surface area it has relative to how loud it is

Answer explanation

The surface area to volume ratio describes how much surface area a cell has relative to its volume (how much space it takes up).

Select the correct word to complete the sentence:

The higher the surface area to volume ratio of a cell, the _________ surface area it has compared to its volume.

Answer explanation

The image below shows a human sperm cell on the left and a human egg cell on the right.

Select which of these cells has a smaller surface area to volume ratio.

• Egg cell

• Sperm Cell

Answer explanation

The larger the cell, the smaller the surface area to volume ratio. This means the egg cell has a smaller ratio, because it is larger.

Select which type of surface area to volume ratio would be the best for effective diffusion.

• A large surface area: volume ratio is best

• A small surface area: volume ratio is best

Answer explanation

A large surface area : volume ratio allows more effective diffusion.

Explain what the surface area to volume ratio is in relation to a cell.

Discuss if a small or large ratio is best for efficient diffusion.

Answer explanation

Surface area to volume ratio describes the amount of surface area the cell has compared to its volume. The cell membrane defines the surface area of the cell. The volume is how much space the cell takes up.

Cells with a large surface area to volume ratio have a large surface area relative to their volume. Cells with a small surface area to volume ratio have a small surface area relative to their volume.

A large surface area to volume ratio is best for efficient diffusion. This is because with a large surface area, more particles (such as the oxygen and nutrients the cell needs to survive) can diffuse across the membrane into the cell. These particles can more easily reach all parts of the cell if a large surface area covers a small volume.