Transportation across all cell membranes Flashcards
Define diffusion
The movement of particles within a liquid or gas from a region of high concentration to a region of lower concentration (down concentration gradient)
Would diffusion take place faster or slower in hotter environments?
Faster as the molecules will have more kinetic energy
Define osmosis
The diffusion of water molecules from a region of high concentration of water molecules to a region of lowers concentration of water molecules
When does diffusion stop
When equilibrium has been reached
What separates active transport from osmosis and diffusion
Active transport requires energy where as osmosis and diffusion are passive
What process does gas exchange in the alveoli use
Diffusion
What process does the absorption of nutrients use
Diffusion
What process does water absorption in the colon use
Osmosis
What process does water uptake in plant roots use
Osmosis
What process does mineral uptake in plant roots use
Active transport
What are the differences between animal cells and plant cells?
Animal cells do not need a cell wall as their structure is held by a cell membrane to keep it rigid
Chloroplasts are only found in plant cells. As they contain chlorophyl which absorbs sun light as plants energy where as animals get their energy from food
Plants cells have larger vacuoles to hold the plant up to stop it from wilting but animal cells do not have the space for them nor need them so they only have small temporary vacuoles
What do animal cells contain?
Cell structure membrane Nucleus Mitochondria Small vacuoles Cytoplasm
What do plant cells contain?
Cell wall Cell surface membrane Cytoplasm Mitochondria Chloroplasts Large vacuole Nucleus
Describe the levels of organisation within oganisms
Organelles, cells, tissues, organs then systems
The rate of diffusion is increased when?
The distance to be diffused deceased
Surface area is increased
The difference in concentration is increased
What does flaccid mean
A plant cell that is limp
What does turgid mean
Plant cell fully inflated with water
What does crenation mean?
Shrinking of an animal cell by osmosis
What does lysis mean
Bursting of an animal cell by osmosis
What factors could affect how slowly or quickly diffusion or osmosis takes place across a cell membrane?
Size of molecules Temperature Difference in concentration on either side Surface area of membrane Ph Kinetic assistance Moistness Surface area to volume ration
Why is it important to have turgid cells in plants?
To keep them upright and stop them from wilting as they have no bone structure to keep the up
