Mitosis And Meosis Flashcards
(39 cards)
What kind of cells undergo mitosis?
Only somatic cells undergo mitosis
What occurs during mitosis? What is the purpose?
A parent cell divides to produce two identical daughter cells which helps the development and maintenance
What happens during early prophase in mitosis?
- Proteins condense
- Centromeres head toward opposite ends and form spindle fibres
- Nuclear envelope and nucleolus disintegrates
- Chromosomes pair up with identical attached to centromere
What happens in late prophase in mitosis?
- Chromosomes are clearly visible
2. Sister chromatids attaches to each pole by spindle fibres
What is genetic continuity?
The transmission of genetic material through cell division
What happens during metaphase in mitosis?
- The chromosomes are visible
- The chromosome line up along the equator of the cell
- It is the longest phase of mitosis
- The centrosomes reach opposite angles of the cell
What happens during anaphase in mitosis?
- The chromatids break away from the centromeres
- Spindle fibres pull the chromatids to opposite ends of the cell
* there are identical halves of chromosomes of each end - The cell elongates
- It is the shortest phase of mitosis
What happens during telophase in mitosis?
- The spindle fibres disappear
- (In animal cells) cell begins to pinch in half
- Chromosomes are less condensed appearing as sister chromatid
- Nuclear envelope reforms
What happens during cytokinesis in mitosis?
- Starts before telophase ends
- Is the second stage of mitosis
- Results in 2 genetically identical daughter cells, divides the cytoplasm and the organelles as well
What happens in animal cytokinesis?
The cell pinches in half dividing the chromosomes, organelles and cytoplasm creating 2 daughter cells
What happens during plant cytokinesis?
The Golgi bodies in the cell create vesicles that line up and create a cell plate which eventually creates the cell wall that divides the 2 daughter cells
What are the 2 main stages of the the cell cycle?
Cell division-which includes mitosis and cytokinesis
Interphase-2 growing stages and DNA replication
What happens during GAP 1 in mitosis?
It is the main growth stage and the cell spend a major part of their life there
What happens during GAP2?
The cell prepares for cell division, organelles replicate, microtubials (pre spindle fibres) are created
Human somatic cells have __ chromosomes or __ pairs of homologous cells.
Human somatic cells have 46 chromosomes or 23 pairs of homologous cells. (One maternal, one paternal in each homologous pair)
Genes for the same trait are not identical. The different forms the same trait are called ________.
Alleles
Where does meiosis happen? Why must it occur?
In the reproductive cells of animals. For gamete production and the continuation of the species.
2 gametes together fertilize to become a diploid zygote. What is the zygote capable of?
The zygote is now capable for mitosis or differentiation
What happens during prophase 1 in meiosis?
- Chromosomes condense forming tetrads (96 chromosomes)
2. The crossing over of genes occur
What happens during metaphase 1 in meiosis?
- Microtubuals move homologous chromosomes to the equator
2. Independent orientation/assortment occurs
What happens during anaphase 1 in meiosis?
- Microtubuals separate the homologous chromosomes (sister chromatids remain together)
What happens during telophase 1 and cytokinesis in meiosis?
2 daughter cells result
What happens between the the 2 meiosis stages?
Interkinesis
What happens during prophase 2 in meiosis?
- It is a very brief stage
2. Spindle fibres form
