Active Transport and Exchange Surfaces

Flashcards covering active transport in root hairs and the gut, and the concept of surface area to volume ratio in organisms.

What do root hairs take in from the soil?

Minerals and water

What is active transport and why is it essential for plant growth?

To absorb minerals from a very dilute solution against a concentration gradient, requiring energy from respiration.

Where else does active transport happen besides plants?

In the gut, to absorb nutrients when the concentration is lower in the gut than in the blood; in the kidney tubules.

When is active transport used in the gut?

When there is a lower concentration of nutrients in the gut than in the blood, which means the concentration gradient is the wrong way for diffusion.

How can you compare surfaces?

By comparing the rate at which substances are exchanged relative to its volume.

What is the surface area to volume ratio of the hippo, based on the image provided?

The surface area to volume ratio of the hippo is 3:1.

What is the surface area to volume ratio of the mouse, based on the image provided?

The surface area to volume ratio of the mouse is 6:1.

Why can single-celled organisms rely on diffusion across the cell membrane?

Because they have a large enough surface area relative to their volume, allowing gases and dissolved substances to be exchanged across the membrane easily.