3.3

meiosis

special form of cell division that creates gametes (sex cells)

asexual

mitosis creates two identical organisms from one individual

sexual

meiosis in different individuals in a population create gametes which combine to make a new organism

gene

individual unit of genetic information, a section of DNA that codes for something

allele

a specific version of a gene, different alleles for the same gene result in slightly different versions of the protein

each gamete contains _____ of the genetic material the adult will have

1/2

homologous chromosomes contain the same genes, but are not

identical and may not have the same alleles

diploid

cells with two copies of each chromosome (humans) (2n)

haploid

cells with one copy of each chromosome (gametes) (n)

mitosis parents divide into

2 identical daughters (new cells and original cell identical)

meiosis parents divide into

4 haploid gametes (NOT identical to original cell, have ½ the DNA)

meiosis 1

homologous chromosomes separate (2)

meiosis 2

sister chromatids separate (4)

during meiosis 1

the duplicated chromosomes line up in the middle of the cell in homologous pairs and then the homologous chromosomes are pulled to opposite ends of the cell

metaphase 1

microtubules attached to chromosome

anaphase 1

sister chromatids remain attached

meiosis 2 is identical to mitosis as

the chromosomes line up in the middle of the cell and then the identical sister chromatids from each chromosome are pulled to opposite ends of the cell (metaphase 2 and anaphase 2)