What does the general cell cycle consist of?
G1, S, G2 and M
What is the G1 phase of the cell cycle?
growth phase where cell enters
what is the S phase of the cell cycle?
where cells replicate all of their DNA
what is the G2 phase?
another growth phase that preps the cell for division
what is the “M” phase?
Mitosis or meiosis(only for sex cells)
What are the 4 phases of division?
prophase
metaphase
anaphase
telophase — cytokinesis
what happens in prophase?
nucleus disassembles and spindles are made and work to attach to the chromosomes
what happens in metaphase?
MEET in the middle (line up on the metaphase plate)
what happens in anaphase?
APART – chromosomes separate to opposite sides
what happens in telophase?
THE end. nucleus is remade and chromosomes start to un-condense
what happens in cytokinesis?
cytoplasm and everything else of the cell separates (making 2 cells)
what are the non-sex cells in mitosis called?
somatic cells
what is the end result of mitosis?
two identical daughter cells are created (identical to mother cell)
what type of cells undergo meiosis?
sex cells
what is the result of meiosis 1?
diploids transition to haploids
what is the result of meiosis 2?
haploid with replicated chromosomes divide into haploids with unreplicated chromosomes
what are homologous chromosomes?
chromosomes with the same genes but not the same alleles
what is an allele?
different versions of the same gene / one version of a gene
what are autosomes?
non-sex CHROMOSOMES
what is a genotype?
what is in the DNA
what is a phenotype?
what the organism looks like
what is a gene?
piece of DNA that encodes for a protein
what is homozygous?
both copies of the gene are the same allele
what is heterozygous?
both copies of the gene are different alleles
what does it mean to be dominant?
the allele that determines the phenotype of the heterozygote
what does it mean to be recessive?
the allele that is “hidden” in the heterozygote
what is incomplete dominant?
heterozygote has a phenotype that does not match either homozygote
what is co-dominance?
heterozygote expresses the phenotype of both parents simultaneously
what is true breeding?
homozygous with a homozygous
what is penetrance?
the percentage of people with the disease mutation actually get the disease
what is expressivity?
the level of variation in phenotype between individuals with the same genotype