Key Area 7- Absorption of materials Flashcards
What needs to be absorbed into the bloodstream and delivered to cells for respiration?
Oxygen and nutrients
What must be removed from cells into the bloodstream?
Waste materials like carbon dioxide
Why do tissues contain capillary networks?
To allow the exchange of materials at cellular level.
What features do materials that absorb materials have in common?
-large surface area
-thin walls
-good blood supply
These increase the efficiency of absorption.
How are lungs adapted from gas exchange?
They consist of a large number of alveoli
providing a large surface area
What is absorbed through the thin alveolar walls to or from the many blood capillaries?
Oxygen and carbon dioxide
How does the small intestine absorb nutrients from food?
The small intestine is folded into tiny villi, this increases the surface area to allow more nutrients to be absorbed.
What does the capillaries do in the small intestine?
To absorb glucose and amino acids
What does the lacteal do in the small intestine?
To absorb fatty acids and glycerol
