B3 exchange of materials
- Created by: isobeld10
- Created on: 08-01-15 20:27
View mindmap
- B3
- Exchange of materials
- Diffusion
- The process by which particles of a move from an area of high concentration to an area of low concentration to create an even concentration
- Example- gaseous exchange in the lungs (oxygen and carbon dioxide)
- Factors the affect diffusion
- Surface area
- Distance or thickness of membrane
- Concentration gradient
- Permeability of surface
- Osmosis
- The movement of water into and out of a cell, from a dilute solution (lots of water) to a concentrated solution, across a partially permeable membrane
- If a cell has a more dilute solution inside of the cell than out side of the cell then the cell can shrivel up
- If this is the other way round then the cell can burst
- Plant cells do not burst as they have turgid cell walls
- If this is the other way round then the cell can burst
- Active transport
- It is used in the gut when there is low concentration of nutrients in the gut but a high concentration of nutrients in the blood
- Active transport works against the concentration gradient
- Active transport- the transport protein carries the useful molecule and rotates using energy (from respiration) and then releases the useful molecule into the cell. The transport protein then rotates back
- Exchange surfaces
- Plants and animals use exchange surfaces in; digestive system, lungs, leaf and roots
- Efficient exchange surfaces have a large surface area, thin surface, and an efficient blood supply (in animals)
- Sports drink dilema-
- Athletes need to replace the lost water, mineral ions and glucose that are used up in exercise
- Sports drinks replace the lost ions that drinking water does not
- There are often claims made by sports drink manufacturer that are not true
- Sports drinks replace the lost ions that drinking water does not
- Athletes need to replace the lost water, mineral ions and glucose that are used up in exercise
- Gaseous exchange in the lungs
- Good gaseous exchange surfaces are thin, large, moist and have good ventilation mechanism and have a good blood supply
- Alveoli are good gas exchange surfaces
- In the alveoli oxygen diffuses from the air into the blood supply and carbon dioxide diffuses from the blood supply into the atmosphere
- Alveoli are good gas exchange surfaces
- Good gaseous exchange surfaces are thin, large, moist and have good ventilation mechanism and have a good blood supply
- Diffusion
- Exchange and transport in plants
- Exchange of water
- Water and ions move into the plant from the roots
- Roots have adapted to absorb water
- Root hairs have large surface area
- Protrusions can can penetrate between soil particles to reduce the distance the ions move
- Water moves through osmosis
- Roots have adapted to absorb water
- Transpiration is the movement of water through the xylem, from the roots to the leaf
- Rate of transpiration increases when light intensity, temperature and air movement are increased
- Rate of transpiration is decreased when humidity is increased as there is more water in the air and less of a concentration gradient
- Water and ions move into the plant from the roots
- Gaseous exchange in plants
- EXCHANGE OF GASES IN THE STOMA
- Function of the stoma:
- Opens to allow diffusion of carbon dioxide into the leaf and oxygen and water vapour out of the leaf
- Stoma closes to retain water
- Guard cells change shape to open and close the stoma
- Function of the stoma:
- EXCHANGE OF GASES IN THE STOMA
- Translocation
- The transport of sugars (made through photosynthesis) through the phloem to areas of the plant to be used or stored
- Exchange of water
- Exchange of materials
Similar Biology resources:
Teacher recommended
Comments
No comments have yet been made