Transport Across Membranes

Question 1

What is diffusion?

Answer 1

The net movement of gas particles from higher concentration to lower concentration.

Diffusion is a passive process that does not require energy.

Question 2

Define osmosis.

Answer 2

The net movement of water molecules across a partially permeable membrane from a region of high water concentration to a lower concentration.

Osmosis is essential for maintaining cell turgor and homeostasis.

Question 3

What is active transport?

Answer 3

The net movement of particles against a concentration gradient using energy released during respiration.

Active transport is crucial for nutrient uptake and waste removal in cells.

Question 4

List factors affecting the movement of substances.

Answer 4

• Distance
• Surface area to volume ratio
• Temperature
• Concentration gradient

These factors influence the rate of diffusion and osmosis.

Question 5

True or False: Shorter distance leads to quicker diffusion.

Answer 5

True

A shorter distance reduces the time it takes for particles to move from one area to another.

Question 6

How does temperature affect the movement of substances?

Answer 6

Higher temperatures result in faster movement of particles.

Increased kinetic energy at higher temperatures accelerates molecular motion.

Question 7

Fill in the blank: Substances move faster if there is a bigger difference in _______.

Answer 7

[concentration gradient]

A steeper concentration gradient increases the rate of diffusion.