Ch 3: Movement Of Substances Across Cell Membrane

Question 1

What are the two main categories of substance transport across the cell membrane?

Answer 1

• Passive Transport (requires no energy from the cell)

- Active Transport (requires energy from the cell)

Question 2

What are the three types of passive transport?

Answer 2

• Diffusion
• Osmosis
• Filtration

Question 3

Diffusion

Answer 3

Molecules move through a membrane in either direction until both sides are equal.

Diffusion occurs because the molecules concentration is greater on one side of the membrane than the other.

Question 4

Osmosis

Answer 4

Movement of water molecules from a region of high concentration to a region of lower concentration

Question 5

What are the three effects of osmosis on cells?

Answer 5

• Hypotonic
• Isotonic
• Hypertonic

Question 6

Hypotonic Solution

Answer 6

A solution that is less concentrated than the fluids within a cell.

Cells in this solution will swell, and may burst.

Question 7

Isotonic Solution

Answer 7

A solution that has the same concentration as the fluid within a cell.

These solutions can be used to replace body fluids.

Ex: normal saline, 5 percent dextrose

Question 8

Hypertonic Solution

Answer 8

A solution that is more concentrated than the fluids within a cell.

Cells in this solution will lose water and shrink.

Question 9

Filtration

Answer 9

Particles in solutions move through a membrane from a place of higher hydrostatic pressure to a place of lower hydrostatic pressure.

Question 10

Active Transport Methods

Answer 10

• Substances move in or out of a cell in a direction opposite of diffusion.
• Molecules move from an area of lower concentration to an area of higher concentration
• Collects what it needs, eliminates waste.