Flashcards
Cells- exchanging substances
Flashcards do conjunto (9)
- 1What is diffusion?Diffusion is the spreading out of particles from an area of a higher concentration to an area of lower concentration. This will process will be faster with a higher temp and high concentration gradient
- 2Name three substances that can diffuse through cell membranes, and two that can't:CAN: dissolved substances, small molecules(oxygen, glucose etc), particles
CANNOT: big molecules (starch/proteins) - 3What is osmosis?The movement of water molecules across a partially permeable membrane from a region of higher water concentration to a lower water concentration.
- 4What is Active transport?Active transport is the process by which dissolved molecules move across a cell membrane from a lower to a higher concentration. In active transport, particles move against the concentration gradient - and therefore require an input of energy from the cell
- 5Give 3 adaptations of exchange surfaces that increase the efficiency of diffusion:thin membrane- short distance to diffuse
large surface area- lots of it at once
lots of blood vessels- into blood quickly
gas exchange surfaces are often ventilated meaning air moves in and out - 6How are villi in the smol intestine adapted?increased surface area, single layer of surface cells (short distance to diffuse substances), good blood supply
- 7How are leaves adapted for the retrieval of carbon dioxide?flattened shape means an increase in surface area, air spaces inside mean more chance for carbon dioxide to get into the cells
- 8How are gills adapted?good blood supply, gill filaments create a larger surface area and smaller lamellae do too, thin surface layer
- 9How are alveoli adapted?large surface area, moist lining for dissolving gases, thin walls, good blood cells
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- GCSE Biology FlashCards sobre Cells- exchanging substances, criado por Clare Noone em 02-06-2018.
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- Clare Noone
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