6.6 Meiosis Flashcards
Meiosis
A specialized form of cell division in Gonads to produce Gametes
What do chromosomes come in?
Homologous pairs
What does a Gamete get?
One of each homologous pairs
How are chromosomes visualized?
By using a Karyotype
What do human Somatic cells contain?
22 pairs of Autosomes and 1 pair of Sex Chromosomes
Are Gametes Haploid or diploid?
Haploid or have 1 set of 23 chromosomes
What forms when an egg and a sperm nuclei fuse?
A zygote
Is a zygote a Haploid or diploid?
Diploid
What other cells are diploid?
Somatic or body cells
What does Meiosis start with?
Interphase
Interphase
DNA is duplicated
What two stages take place during Meiosis?
Meiosis I and Meiosis II
Meiosis I
Separating out the homologous pairs into 2 separate cells
Meiosis II
Separating out the sister chromatids in each cell to produce 4 Haploid cells
Crossing Over
Exchange of equivalent portions of chromosome between members of a homologous pair which results in new types of Gametes being formed
Linked Genes
Typically cross over together
Random Alignment
The way in which different pairs of chromosomes align and get separated during Meiosis I is random
Nondisjunction
Failure of homologues to separate normally during Meiosis
What are the results of Nondisjunction?
Results in a Gamete having one too many chromosomes (Trisomy) or one too few chromosomes (Monosomy)
Do embryos resulting from Nondisjunction survive?
No, they die before birth
How are cancer mutations passed on to offspring?
The mutations must take place in cells that give rise to Gametes
Are mutations in Somatic cells heritable?
No
