Mitosis Flashcards
Define: Cell division
Process by which cells make more cells
What are the 2 ways which cell divison can occur?
Occur through mitosis (body cells) or meiosis (germ or sex cells)
What is cancer
Overactive cell division
Explain the size and DNA location of Eukaryotes
Genome large and linear
DNA in nucleus
Explain the size and DNA location of Prokaryotes
Genome small and circular
DNA in cytoplasm
Explain G Phase
G phase - double the amount of everything needed, cell grows by producing protein
Explain S Phase
S phase - dna is duplicated
Explain G2 phase
G2 phase - cell prepared to enter into mitosis
Explain M phase
M phase (mitosis) - chromosomal separation and cytokinesis
What is interphase
Interphase - time between successive mitosis
Explain the phases of the cell cycle
Interphase (G, S, G2p phase), Mitosis (PMAT, cytokinesis)
What happens to cells not actively
- May exit cell cycle
- From G1, enter state of G0
- These cells are said to be quiescent (inactive)
How many chromosomes of in a human genome
23 pairs of chromosomes
How many autosomes and sex cells are in human genomes
1-22 is autosomes
23 is sex chromosome - determine sex
What are homologous chromosomes
- Chromosomes that belong together
- Of common descent
What are centromeres
Centromeres - central part of chromosomes important for separating spindle fibres
What happens to chromatids in the S phase
Through S phase, chromatids double making are sister chromatids (still same amount of chromosomes)
What is mitotic cell division
Mitotic Cell Division: a single parent cell divides into 2 daughter cells
What happens in prophase
Chromosomes condense
Centrosomes radiate microtubes and migrate to opposite poles
What happens in pro-metaphase
Microtubules of the mitotic spindle attach to chromosomes
Nucleus envelope begins to break
What happens in metaphase
Chromosomes align in center of cell
What happens in anaphase
Sister chromatids separate and travel to opposite poles
– Sister chromatids become individual chromosomes when the centromere is split
What happens in telophase
Nuclear envelopes re-form and chromosomes decondense
What is cytokinesis
Physical process of cell division that divides the cytoplasm of the parent cell into 2 daughter cell
How long does it take cells in culture to complete 1 cell cycle
Take 24 hours to complete 1 cell cycle
What are ploidy levels
of complete sets of chromosomes in a cell is known as its ploidy
What are haploid cells
Cell with 1 complete set of chromosomes in haploid
What is the ploidy of haploid cells
1n
What are an example of haploid cells
Ex. sperm cell or an egg in vertebrates
What are diploid cells
Diploid cell would have 2 complete sets of chromosomes. One from mother, and one from father
Whats the ploidy of diploid cells
2n
What are examples of diploid cells
Ex. somatic cell such as leaf cell
Ex. Skin cell
Ex. stem cell in colon
What happens to diploid somatic cells after S phase
DNA doubles making a complete set of chromosomes
Still a diploid cell
Does DNA or ploidy change in mitosis?
Amount of DNA changes but NOT the ploidy levels in Mitosis
