Movement into and out of cells：练习题

Which process is defined as the net movement of particles from a region of their higher concentration to a region of their lower concentration as a result of their random movement?

What is the definition of active transport in living organisms?

The uptake of mineral ions into a root hair cell is observed to decrease significantly when the cell is treated with a chemical that stops aerobic respiration. What is the most likely explanation for this observation?

Which process involves the net movement of particles from a region of their higher concentration to a region of their lower concentration as a result of their random movement?

A student investigates the rate of diffusion using different conditions. Which set of conditions would result in the highest rate of diffusion across a membrane?

Describe the factors that influence the rate of diffusion and explain how a decrease in temperature affects this rate.

A scientist observes that root hair cells can absorb mineral ions from the soil even when the concentration of these ions is lower in the soil than inside the cell. However, if a plant is placed in very salty water, its root hair cells become flaccid and the plant wilts. Explain the biological mechanisms responsible for these two observations, highlighting the energy requirements for each process.

A plant cell is placed in a concentrated salt solution. Explain the changes that occur in the cell's vacuole and cell membrane using the term plasmolysis.