Cells- exchanging substances

Description

GCSE Biology Flashcards on Cells- exchanging substances, created by Clare Noone on 02/06/2018.
Clare Noone
Flashcards by Clare Noone, updated more than 1 year ago
Clare Noone
Created by Clare Noone almost 6 years ago
17
0

Resource summary

Question Answer
What 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
Name 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)
What is osmosis? The movement of water molecules across a partially permeable membrane from a region of higher water concentration to a lower water concentration.
What 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
Give 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
How are villi in the smol intestine adapted? increased surface area, single layer of surface cells (short distance to diffuse substances), good blood supply
How 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
How are gills adapted? good blood supply, gill filaments create a larger surface area and smaller lamellae do too, thin surface layer
How are alveoli adapted? large surface area, moist lining for dissolving gases, thin walls, good blood cells
Show full summary Hide full summary

Similar

Fossils and evolution (edexcel)
10ia3416
Biology- Genes and Variation
Laura Perry
Biology Revision - Y10 Mock
Tom Mitchell
GCSE Biology B2 (OCR)
Usman Rauf
GCSE AQA Biology - Unit 2
James Jolliffe
AQA Physics P1 Quiz
Bella Statham
GCSE AQA Physics - Unit 3
James Jolliffe
GCSE AQA Physics 1 Energy & Efficiency
Lilac Potato
The Circulatory System
Johnny Hammer
Plant and animal cells
Tyra Peters
F211- Module 1 Cells, exchange and transport
eilish.waite