CELLS: Investigating Mitosis Flashcards
1
Q
Describe how root tips can be used to investigate mitosis:
A
- Cut 1 cm from tip of growing root - where mitosis takes place
- Prepare boiling tube - 1M hydrochloric acid
- Put in water bath at 60oC
- Transfer root tip into boiling tube + incubate for 5 minutes
- Use pipette to rinse root tip with cold water
- Leave to dry
- Place on microscope slide + cut 2mm from tip
- Use mounted needle to break tip open + spread cells.
- Add stains
- Place cover slop + push firmly
2
Q
Describe how to use an optical microscope:
A
- Clip slide onto stage
- Select lowest-powered objective lens
- Use coarse adjustment knob to move stage up
- Use coarse adjustment knob to move stage downwards until image is roughly focused.
- Adjust focus with fine adjustment knob
- If greater magnification needed = higher-powered objective lens
3
Q
How do you calculate mitotic index?
A
= number of cells with visible chromosomes / total number of observed cells