Transport In Cells Flashcards
What diffusion?
Where particles of a high concentration move to a low concentration
What’s the difference in concentration called?
Concentration gradient
Give an example of diffusion in cells
CO2 moves into cells by diffusion(cells) in photosynthesis
Give the factors diffusion can be affected by
Concentration gradient
Temperature
Surface area of the cell membrane separating different regions
How does the concentration gradient affect diffusion?
The greater the difference in concentration, the quicker the rate of diffusion
How can temperature affect the rate of diffusion?
Higher the temp- more kinetic energy the particles will have- so they’ll move more quickly
How can surface area affect the rate of diffusion?
The greater the surface area, the faster the rate of diffusion
Give the aim of the practical- investigation the effect of concentration on rate of diffusion
To determine if higher concentrations diffuse faster
Give the risks for the practical investigation the effect of concentration on rate of diffusion
hydrochloric acid is corrosive- if it touched the skin it should be washed off
- goggles should be worn at all times
What shows greater diffusion in the diffusion practical?
If as the concentration of hydrochloric acid increased the distance the colour change of the agar, from pink to colourless also increased
What’s osmosis?
The diffusion of water molecules, from a high concentration to a low concentration through a partially permeable membrane
What substance does osmosis only refer to?
Water molecules
How will water move in and out of cells?
Through osmosis
What’s supports the cell from bursting when taking in water from osmosis?
The strong cellulose cell wall outside the cell membrane
What happens to cells from osmosis in pure water?
The cell contents push against the cell wall and the cell becomes turgid( enlarged and swollen with water). Fully turgid cells support the stem of non-woody plants
What happens to plant cells in concentrated water
The cell contents lose water by osmosis and the cells shrink. The cell membrane starts to pull away from the cell wall. The cell become flaccid( soft and floppy)
What is plasmolysis?
In a very concentrated solution, the cell membrane pulls away from the cell wall completely
What happens if animal cells lose or gain too much water by osmosis?
They don’t function efficiently
Give the formula for water uptake in an hour
Water uptake in 1 hour= change on mass X 60 mins/ length of experiment in mins
Give the change in mass formula
Change in mass= mass at end-mass at the start X 100
Give the formula for ordered rank
Percentile/100 X number of entries in data set
What’s active transport?
A process that is required to move molecules against a concentration gradient. It requires energy
Give an example of active transport
-mineral ions into plant roots
-glucose from the gut into intestinal cell- from where it moves into the blood
Give a description of active transport
Substances move from a low to high concentration up a concentration gradient
