Lab 13: Mitosis and Meiosis Flashcards
What is the purpose/function of mitosis in the human life cycle?
Of Meiosis?
The prupose/function of mitosis in the human life cycle is to create two identical daughter cells with the same number of chromsosomes from one cell.
The purpose is for growth and and to replace worn out cells.
Involves somatic cells: muscle cells, liver cells, skin cells, eye cells.
For Meiosis the function is to create 4 haploid cells from a diploid cell with half the amount of chromosmes as the parent cell.
Purpose to produces gametes: sperm and egg
What happens during interphase? When is DNA replicated?
In Interphase is where cells take most of their time. Interphase is the stage where the cells grow and DNA is replicated. Partakes in th G1 Phase, S phase, and G2 Phase.
DNA is replicated in the S phase. After its been through the G2 phase to gather everything it needs and goes through checkpoints its clear to replicate.
Describe what is happening during the steps of Mitosis.
In Mitosis:
Interphase: DNA is replicated and the cell is fully grown.
Prophase: nucleus is broken down, chromosomes condense, and the mitotic spindle begins to extend.
Prometaphase: Some mitoic spindles attach the kinetochores of the chromosomes and chromsomes finsih condensing.
Metaphase: Mitotic spindles fully attach to each sister chromosomes from opposite sides and they are lined up in the center of the cell.
**Anaphase: **: Sister chromatids are sperated as the mitotic spindles move to opposite ends of the cell.
Interphase: the sister chromatids are brough to opposite ends of the cell and the chromosomes begind to decondense causing the cell to from a nucleus once more.
Cytokinesis: the cell is cleavage furrow sperates the cells in animal cells and in plant cells new cell wall is formed.
Describe what is happening during the steps of Meiosis.
Meiosis 1;
**Interphase: **DNA is replicated.
Prophase 1: Chromsomes are combined crossed over and synapsis occurs where DNA is shared between homologous chromsomes.
Metaphase 1: Homologous chromosomes are aligned randomly in the center of the cell and attached by mitotic spindles.
Anaphase 1: Homologous chromsomes are seperated on oppoiste ends of the cell.
**Telophase 1 **: The sister chromatids now decondense and nuclues begins to form.
**Cytokinesis: **Cleavage furrow seperated the cells into two daughter cells.
Meiosis 11:
Same process as mitosis only 2n daughter cells are now slit into 4 haploid cells.
When do sister chromatids separate in Mitosis?
In Meiosis?
Sister chromatids are seperated in ANaphase of Mitosis.
Sister chromatids are seperated in Anaphase 2 of Mitosis.
What are the big difference between Mitosis and Meiosis?
Mitosis produces two identical daughter cells with same number of chromosomes.
Meiosis prouces 4 haploid cells with half the number of chromsomes.
Involves homologous pairs that are crossed over.
Metaphase 1 seperates homologous pairs to forme sister chromatids.
How do these relate to their function?
Mitosis is needed in Meiois 11. Since two diploid cells are formed in the first part of Mitosis then through mitosis they are able to divide and form 4 new haploid cells.
