Transport Across The Cell Membrane Flashcards Preview

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Flashcards in Transport Across The Cell Membrane Deck (12)
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1
Q

What does the term semi/selectively permeable mean? Give an example

A

The cell membrane controls the passage of substances that enter and exit the cell and this is described as semi/selectively permeable

2
Q

Explain the term concentration gradient

A

The concentration gradient is the difference in concentration that exists between the region of high concentration and a region of low concentration

3
Q

Explain the term passive transport.

Give an example

A

Diffusion is a form of passive transport because no energy input is needed for diffusion to occur

4
Q

State the definition of osmosis

A

Osmosis is a special case of diffusion.
It is the movement of water molecules from a region of high water concentration to a region of low water concentration across a selectively permeable membrane

5
Q

Describe the effect of placing an animal cell in concentrated, dilute solutions and water

A

Concentrated- the water moves out of the cell and the cell shrinks
Dilute- the water moves in both directions and stays the same
Water- the water enters the cells and the cell bursts

6
Q

Describe the effect of placing a plant cell in concentrated, dilute solutions and water (using the words plasmolysed and turgid)

A

Concentrated- the water moves out the cell and the cell becomes Plasmolysed
Diluted- the water moves in both directions and cell stays the same
Water- the water moves into the cell and it swells and becomes turgid

7
Q

What does plasmolyse mean?

A

When the vacuole shrinks and the cell membrane pulls away from the cell wall it is called plasmolyse

8
Q

State the definition active transport

A

Active transport is the movement of icons and molecules across the cell membrane from a low to a high concentration against a concentration gradient

9
Q

State 2 main differences between active transport and diffusion

A
  • active transport requires energy

- active transport is a low to high concentration where as diffusion is a high to low concentration

10
Q

What type of molecules act as carrier molecules?

A

Proteins

11
Q

Where are the carrier molecules located?

A

Cell membrane

12
Q

State the components of the cell membrane

A

Lipids and proteins