diffusion Flashcards
diffusion
the spreading out of particles from an area of high concentration to an area of low concentration
what states of matter does diffusion occur in and why?
liquids and gases as the particles in those substances are free to move around
give three examples of diffusion
- oxygen diffuses from the lungs into the blood
- carbon dioxide diffuses from the blood into the lungs
- urea diffuses from kidney cells into blood plasma
what effect does the concentration gradient have on diffusion?
the bigger the concentration gradient, the faster the diffusion rate
what effect does the temperature have on diffusion and why?
it will increase the diffusion rate because the particles will have more energy so will move faster
what effect does the surface area have on diffusion and why?
the larger the surface area of the membrane, the fast the diffusion rate as more particles can pass through at once
give 4 examples of small molecules that can diffuse through cell membranes
- oxygen
- glucose
- amino acids
- water
how do dissolved substances move in and out of cells?
they diffuse through the cell membrane
3 main factors affecting diffusion
-concentration gradient
-temperature
-surface area
how are single celled organisms adapted for diffusion?
large surface area to volume ratio which maximises diffusion rate
what is a concentration gradient?
the difference in concentration between two areas
will oxygen move out of a cell faster if it has a higher or lower concentration?
lower concentration