3.2 - The Cell Cycle Flashcards
What are the 3 main stages in the cell cycle?
- Interphase
- Mitosis
- Cytokinesis
What occurs in interphase?
- Cell grows, new organelles are made, DNA replicated
What four stages occur in mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
What are the three steps in interphase?
- G1 (growth and protein synthesis)
- S (DNA replication occurs)
- G2 (growth and protein synthesis)
What happens in prophase?
Chromosomes become visible, nuclear envelope breaks down, nucleolus disappears, spindle forms, centrioles move to poles
What happens in Metaphase?
Chromosomes, each consisting of sister chromatids, align and attach to spindle fibres, attached to centrioles
What happens in anaphase?
Spindle fibres contract and pull chromatids apart
What happens in telophase?
Chromosomes decondense and become invisible. Membrane of nucleus and nucleolus form. Cells begin to split apart
What steps are there in root tip preparation?
- Cut 5mm of root tip
- Soak in acid to soften
- Break open and crush (macerate)
- Add toluidine blue stain
- Warm sample to intensify stain
How many types of human cell are there?
216
What does totipotent mean?
The stem cell can specialise and differentiate into any type of cell
What does pluripotent mean>
The stem cell can specialise and differentiate into multiple, but not all, types of cell
What is a blastocyst?
A hollow ball of cells with an inner cell mass of 50 cells
Are the 50 central cells in a blastocyst totipotent or pluripotent?
Pluripotent
What can stem cells be used to treat?
- Parkinson’s disease
- Multiple Sclerosis
- Type 1 Diabetes
- Burns
