Biology Paper 1 - Cell Structure Flashcards
Differences between eukaryotic cells and prokaryotic cells
Eu contains cell membrane, cytoplasm and genetic material in nucleus.
Eu does not contain plasmids in the cells
Eu are much bigger than Pro
Sub-cellular structures in plant cells
Both: nucleus, cytoplasm, cell membrane, mitochondria, ribosomes
Plant: Chloroplasts, permanent vacuole filled with sap, and cell wall made of cellulose to strengthen cell.
How is sperm cell specialised cell?
Long tail/flagella
Middle section of mitochondria for energy
Acrosome stores digestive enzymes
Large nucleus
How is nerve cell specialised?
Lots of dendrites (connections to other nerve cells)
Axons (carries impulse)
How is muscle cell specialised?
Striated muscle cells: muscles contract and relax in pairs
Mitochondria
Stores glycogen
How is root hair cell specialised?
Increased SA
Large permanent vacuole
Mitochondria for Active Transport
How is xylem cell specialised?
Lignin builds up in cell wall: water and mineral ions can more easier
Rings of lignin makes them very strong
How is phloem cell specialised?
Cells walls between cells can break down
Lose internal structures but supported by companion cells
Mitochondria of companion cells transfer energy
What happens when a cell differentiates?
Acquires sub-cellular structures which enable it to carry out a specific function
How does bacteria multiply?
Binary fission which produces genetically identical cells
Binary fission
Asexual reproduction where a single cell duplicates its genetic material and separates into 2 daughter cells
2 environments bacteria can be grown
A nutrient broth solution
Colonies on agar gel plate
Why must Petri dish be sterilised?
To kill off any unwanted microorganisms
Why sterilise the inoculating loops?
Prevent unwanted microorganisms from getting in
Why store the Petri dish upside down?
To prevent condensation from falling from the lid onto the agar jelly
