Bio Meosis

mitotic

Many organisms reproduce asexually by what division?

identical

In mitotic division, the offspring are genetically different or identical?

mutation

What is a change in DNA called?

gamete

In sexually reproducing organisms each parent donates what?

sex cell

What is a gamete?

homologus

Chromosomes occur in what type of pairs?

father and mother

In chromosomes, one of each pair is from who?

germ cell

Gametes develop from cells called?

Diploid

Sex cells can't be what?

production of gametes

When does meiosis happen?

half

In meiosis, it reduces chromosomes by how much?

2

Meiosis occurs in how many parts?

DNA is replicated

Before meiosis I what happens?

1.) chromosomes condense

2.) spindle forms

3.) homologous chromosomes pair up

4.) crossing over occurs

5.) nucleus envelope breaks open

6.) spindle microtubules attach to each chromosomes

What happens in Prophase 1?

synapsis

How do homologous chromosomes pair up?

chromosomes pairs line up on equator

What happens in metaphase 1?

chromosomes (not chromatids) are moved away from homologous partners and towards opposite ends

what happens in anaphase 1?

1.) cytoplasm divides

2.) 2 haploid daughter cells are made(still consist of chromatids)

what happens in telophase 1?

mitosis

Meiosis 2 is a lot like what?

spindle microtubules attach to centromere

what happens in prophase 2?

lined up single file along the equator

what happens in metaphase 2?

chromatids separated and pulled to opposite poles

what happens in anaphase 2?

1.) nuclear envelopes form around each set of chromosomes

2.)spindle breas up

3.) chromosomes relax

4.) New 4 haploid daughter cells (sister chromosomes)

what happens in telophase 2?

1 diploid germ cell ----> 4 haploid sperm

What is produced in spermatogenesis?

1 diploid cell-------> 1 haploid ovum and 2 polar bodies that denigrates

what is produced in oogenesis?

genes in a different combination than parents had

what is genetic recombination?

-crossing over (prophase 1 )

-spindle microtubules align the chromosomes and have a combination of maternal and paternal chromosomes that end up on either side of the equator is random (prophase1 -metaphase 1)

what two points in meiosis 1 allows for genetic recombination?

1.) homologous chromosomes pair up (synapse)

2.) non sister chromatids undergo interaction when both break at the same point and ends are traded

3.) 2/4 chromatids there is a new combination

what is crossing over?

the spindle microtubules attaching to chromosomes pull them to the equator randomly

When chromosomes line up for metaphase 1, how does genetic recombination happen?

Fertilization

When egg and sperm get together randomly is called what?

sex

What allows for a lot of genetic variation among the population?

cell organisms

Alteration of meiosis and fertilization is common to what?