1What is the longest stage?
Interphase
2What happens in interphase?
Replication of organelles + DNA
New organelles made
Synthesis of ATP and proteins
Cell size increases
Cell mass doubles
3What are the stages of mitosis?
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
(IPMAT)
4What happens in Cytokinesis?
Cytoplasm pinches and divides, 2 cells created (animal)
Cell plate grows from inside and moves out, splitting cell wall (plants)
5What is Mitosis?
Produces daughter cells that are genetically identical to mother cells
Asexual reproduction
Growth, repair
6What are homologous chromosomes?
Paired chromosomes with genes in the same locations
May have alleles of those genes
7What happens if the gene that controls mitosis is damaged?
Uncontrolled mitosis occurs, rapid replication forms tumors, causing cancer.
8What is the gene that causes cancer called?
Oncogenes
9What happens in Mitosis Prophase?
Chromosomes condense, become visible
Centrioles move to poles
Nuclear envelope disintegrates
Centrioles form spindle fibres
10What happens in Mitosis Metaphase?
Centromeres of the chromosomes line up on equator
Spindle fibres attach to centromeres
11What happens in Mitosis Anaphase?
Spindle fibres shorten (ATP needed for it)
Each chromosome separated and pulled to each pole
12What happens in Mitosis Telophase?
Spindle fibres disintegrate
Nuclear envelope reforms
Chromosomes decondense
13What is the difference in cell division for plant cells?
Theres no centrioles in plant cells
Cell plate develops from inside out during cytokinesis
14What is Meiosis?
Takes place in ovaries and testes
Produces gametes
2 different events for division (I and II)
15What happens in Meiosis Prophase I?
Chromosomes form bivalents
Arms of chromatids may cross over, gen material exchanged between homologous chrmsms- form chiasmata, increases variation
16What happens in Meiosis Metaphase I?
Homologous chromosomes arrange in pairs and line on equator
Independent assortment occurs
17What is independent assortment?
Homologous chromosomes from parent A and B arrange themselves randomly along spindle facing each pole
18What are bivalents?
Pairs of homologous chromosomes
19What happens in Meiosis Anaphase I?
Chromosome bivalents separate, each chromosome pulled by centromere toward opposite poles
20What happens in Meiosis Telophase I?
Nuclear envelope reforms around chromosomes at poles
Chromosomes no longer in pairs, cells are haploid
Prophase II starts immidiately after
21What happens in Meiosis stage II?
Exactly the same as Mitosis
In a new nucleus
Cytokinesis at end, results in 4 geneticallt varied cells.
22What no. of cells can only divide by mitosis?
Haploid cells
23What are the differences in the no. of nuclear divisions?
Mitosis- 1 division
Meiosis- 2 divisions
24What are the differences in the no. of cells formed?
Mitosis- 2
Meiosis- 4
25What are the differences in ploidy of parental cells?
Mitosis- 2n diploid
Meiosis- 2n diploid
26What are the differences in ploidy of daughter cells?
Mitosis- 2n diploid
Meiosis- n haploid
27What are the differences in genetic nature of daughter cells?
Mitosis- Identical
Meiosis- Varied
28What are the differences in pairing of homologous chromosomes?
Mitosis- No pairing
Meiosis- pairing to form bivalents
29What are the differences in crossing over?
Mitosis- None
Meiosis- Cross to form chiasmata
30What are the differences in segregation of homologous chromosomes?
Mitosis- No segregation
Meiosis- Bivalents separate