Cell Biology Flashcards
What happens in binary fission ?
- plasmid replicated
- cell gets bigger and plasmids move to opposite poles
- cytoplasm divides and new cell wall forms
- each new cell has a copy of the plasmid
What is cell differentiation
The process by which a cell changes to become SPECIALISED to for a certain job
What changes happen within a cell during differentiation
Different subcellular structures form and it becomes a new cell suited for specific functions
When is cell development peaked in animal and plant cells
Early development in animal cells and never stops in plants
What are undifferentiated cells called
Stem cells
What are the 5 examples of specialised cells
Sperm, Nerve, Muscle cells, Root hair, phloem and xylem
How are phloem and xylem specialised for their job
Long cells with hollow centres to allow easier transport
What are chromosomes
Coiled up lengths of dna molecules
What do chromosomes do
Carry large numbers of genes which control different characteristics
What is mitosis
The cloning of cells to replace or repair damaged cells and allow for growth
What are prokaryotes
Cells where the DNA is not stored in a nucleus
What are the organelles within prokaryotic cells
No mitochondria, single strand of DNA that floats freely, plasmids (small rings of dna) cell wall and membrane
What is an example of a prokaryotic cell
Bacteria’s
What are eukaryotic cells
Cells where the dna is stored within the nucleus
What are examples of eukaryotic cells
Animal and plant cells
What do eukaryotic cells contain (both plant and animal) ?
-Nucleus
-cytoplasm
-cell membrane
-mitochondria
-ribosomes
What do just plant cells contain
- cellulose Cell wall
-Permanent vacuole
-chloroplasts
Why do we use microscopes
Easier to see organelles
What are the advantages of light microscopes
Cheap
What are the advantages of electron microscopes
Larger magnification
Better resolution
Than light microscopes
How do you work out magnification
Image size \ real size
What is the microscope RP
- Add a drop of water to a clear slide
- Cut onion into separate layers and then peel off epidermis tissue
- Using tweezers place tissue onto the water on the slide
- Add a drop of iodine to stain sample
- Place cover slip over top to seal
What is the Culturing microorganisms RP
Bacteria cultured in either nutrient broth or agar jelly
Growth on agar forms visible colonies
Why is the bacteria cultured at 25 degrees
To not create human pathogens
