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What is the goal of meiosis? . To create haploid cells from diploid cellsAnother way of thinking about it is Somatic cell -> gamete . Meiosis Vocab. GenesA discrete unit of hereditary information consisting of a specific nucleotide sequence in DNASomatic cellA diploid body cell Gamete a h
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1. IB Biology Review Chapter 13: Meiosis
2. What is the goal of meiosis? To create haploid cells from diploid cells
Another way of thinking about it is
Somatic cell -> gamete
3. Meiosis Vocab Genes
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA
Somatic cell
A diploid body cell
Gamete
a haploid cell such as an egg or sperm
Asexual reproduction
Type of reproduction that involves one parent producing two identical offspring by budding or binary fission
Sexual reproduction
Type of reproduction in which two parents produce offspring with unique combinations of genes
4. Meiosis Vocab Cont. Diploid cell
Cell with two sets of chromosomes (2n), one from each parent
Haploid cell
Cell with one set of chromosomes; gamete
Autosome
A chromosome that is not directly involved in determining sex
Sex chromosome
One of the pair of chromosomes responsible for the sex of an individual
Zygote
The diploid product of the union of haploid gametes in conception; a fertilized egg
5. Meiosis Vocab cont. Synapsis
The pairing of replicated homologous chromosomes during prophase I of meiosis
Crossing over
The reciprocal exchange of exchange material between non-sister chromatids during prophase I of meiosis
Chiasma / Chiasmata (plural)
The X-shaped, microscopically visible region where homologous chromatids exchange genetic material in crossing over
Tetrad
A paired set of homologous chromosomes, composed of two sister chromatids
Forms during prophase I of meiosis
Recombinant chromosome
A chromosome created when crossing over combines the DNA from two parents into a single chromosome
Nondisjunction
An error in meiosis where chromosomes fail to move apart correctly
Can lead to an abnormal number of chromosomes in gametes
6. What are the stages of meiosis? Prophase I
Metaphase I
Anaphase I
Telophase I and cytokinesis I
Metaphase II
Anaphase II
Telophase II and cytokinesis II
7. What happens during prophase I? Chromosomes condense / coil / become shorter and fatter Homologous chromosomes pair up Crossing over /chiasmata form