B2, B3, B4 Flashcards
What is the definition of osmosis?
Osmosis is the movement of water molecules through a partially permeable membrane eg cell membrane
What is crenation?
Animal cells placed in concentrated solution will lose water and therefore shrivel
What is lysis?
Animal cells placed in a dilute solution will take in water and therefore burst
How do you find the magnification
Size of image divided by the size of real object
How do you find size of real object
Size of image divided by magnification
What is the cytoplasm
A liquid gel where all chemical reactions take place needed for life to exist
What is the mitochondria
Structures in the cytoplasm where aerobic respiration takes place which releases energy from the cell
Are all animals eukaryotes
Yes
What do eukaryotic cells contain
A cell membrane cytoplasm and genetic material (DNA)
What is an example of a prokaryotes
Bacteria
Does bacteria have cell walls
Yes
What are nerve cells designed to do
To carry electrical impulses around the body of an animal
What are muscle cells designed to do
They contract and relax when in pairs to move the bones of the skeleton
What does the nucleus do?
The nucleus controls all the activities of the cell and is surrounded by the nuclear membrane
What does the cell membrane do
Controls the passage of substances going in and out of the cell
What does the mitochondria do
Structures in the cytoplasm where aerobic respiration takes place releasing energy from the cell
What does the ribosomes do
Where protein synthesis takes place making all the proteins needed in the cells
What do the chloroplasts do
They contain chlorophyll which makes light running so photosynthesis can occur
What is diffusion
The movement of particles from an area of high concentration to an area of low concentration
How does the rate of diffusion increase
- Having a large surface area
- Being thin to provide a short diffusive distance
- Being ventilated
Carbon dioxide + water –> ??
Oxygen + glucose
What is the waste product of respiration
Carbon dioxide
What is the difference between osmosis and diffusion
Diffusion involved gas or dissolved molecules, but osmosis involves the movement of water
What happens when cells are placed in distilled water
Cells swell and burst. This is called lysis
What happens when cells are placed in concentrated salt solution
Cells will shrink and shrivel. This id called crenation
What does turgid mean
When the cell wall is structured not to burst
What does flaccid mean
When the cell shrivels it causes the cytoplasm to pull away from the cell wall so it becomes flaccid
