Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
10 Cards in this Set
- Front
- Back
What are the two ways in which dissolved substances move? |
Diffusion and Active transport |
|
What is osmosis? |
The diffusion of water from a dilute to a more concentrated solution through a partially permeable membrane that allows the passage of water molecules. |
|
What do most soft drinks contain? |
Water, sugar and ions |
|
Why do sports drinks contain sugars, water and ions? |
To replace sugar, water and ions during energy release in activity and sweating. |
|
What happens when water and ions are not replaced? |
Balance of ion/water is disturbed and cells work inefficiently |
|
What is active transport? |
The process of substances being absorbed against a concentration gradient, and requires energy from respiration |
|
How is the effectiveness of an exchange surface area increased? (4) |
Large surface area Being thin for a short diffusion path Having an efficient blood supply Being ventilated |
|
How is the surface of lungs increased in humans? |
By the alveoli |
|
How is the surface area of the small intestine increased in humans? |
By the villi |
|
What is the function of the villi? |
Provides a large surface area with an extensive network of capillaries to absorb the products of digestion by diffusion and active transport. |