P1P2B1 - Key concepts Flashcards
What is Osmosis?
The movement of water molecules from an area of high concentration to an area of low concentration across a partially permeable membrane.
What is Active transport?
The movement of molecules from an area of low concentration to an area of high concentration against a concentration gradient, using energy from respiration.
What is Diffusion?
The movement of molecules from an area of high concentration to an area of low concentration, down a concentration gradient.
What are Prokaryotic cells? Example?
Cells without a nucleus. EG - Bacteria
What are Eukaryotic cells? Example?
Cells with a nucleus. EG - Animal cell, fungi
How large can Prokaryotic cells be?
0.1 - 5.0 Micrometres (μm)
How large can Eukaryotic cells be?
10 - 100 Micrometres (μm)
What are key features of Prokaryotic cells?
- Prokaryotic cells may have one or more small rings of DNA, which are called plasmids which can replicate and move between cells so that genetic information is shared.
- Single DNA loop (Stored in Cytoplasm)
- No mitochondria or chloroplasts
What are key features of Eukaryotic cells?
NA
What 5 sub-cellular structures are found in an animal cell? Functions?
- Nucleus = Stores DNA, controls the cell.
- Mitochondria = Aerobic Respiration.
- Cytoplasm = Jelly like substance, where most chemical reactions take place.
- Cell membrane = Controls what enters and exits, partially permeable.
- Ribosomes = Protein Synthesis
What are 3 extra sub-cellular structures found in plants but not animal cells? Functions?
- Permanent vacuole = Keeps cell firm and rigid, stores cell sap and water.
- Chloroplasts = Contains chlorophyll, site of Photosynthesis.
- Cell wall = Protects and supports the cell, made of cellulose.
What are Plasmids?
Small rings/loops of DNA.
What are some structural components of a bacterial cell?
- Single DNA loops
- Plasmids
- Flagella
What are the 3 digestive enzymes?
- Amylase
- Lipase
- Protease
What is an enzyme?
A biological catalyst that speeds up the rate of reactions.
Equation for magnification?
Size of image / Size of real object