Cells: All cells arise from other cells Flashcards
Define tumour:
A swelling in an organism made up of cells that continue to divide in an abnormal way.
What type of cell division produces genetically identical cells?
Mitosis
What do the newly produced cells from mitosis replace?
Old/damaged cells
What is a diploid cell?
A cell that has two sets of chromosomes.
What type of cell division produces diploid cells?
Mitosis
What are haploid gametes?
Sex cells that have half the normal amount of chromosomes.
What type of cell division produces haploid gametes?
Meiosis
What are the two main stages that make up the cell cycle?
- Interphase
- Mitosis
What are the three stages that occur in interphase?
- Growth stage 1
-Synthesis of DNA (S-phase)
-Growth stage 2
What happens in stage Growth stage 1 during interphase?
- Replication of organelles, e.g. mitochondria, ribosomes
What happens in synthesis of DNA stage during interphase?
- Replication of DNA (DNA content will double)
What happens in growth stage 2 during interphase?
- Checks that cell is ready for mitosis
In what stage of interphase does cell cycle arrest occur?
G1
What happens in cell cycle arrest?
- Cell cycle stops
- Cell ‘rests’
What are checkpoints in the cell cycle?
Stages where the cell is checked to ensure that it is ready to move on to the next phase of the cell cycle.
What are checkpoints controlled by?
Genes that code for proteins