Genetics (Part 1) Flashcards
Where does crossing over occur?
- Prophase 1
What is happening during crossing over?
- The chromatin line up next to each other and for a tetrad
- Exchange genes with each other
Why is crossing over important?
- Crossing over helps achieve genetic diversity, each cell is different
Where does Independent Assortment occur?
- Metaphase 1
What is happening during Independent Assortment?
- Homologous chromosomes randomly line up during the Metaphase 1. How they line up will result in different combinations of chromosomes in the final cells.
Why is Independent Assortment important?
- Assists with genetic diversity, no cell is the same.
What is genetic diversity?
- Different genes within a cell
Why is Meiosis important?
It insures that all organisms produced by sexual reproduction have the correct amount of chromosomes
What is Meiosis?
- Process of reduction division in which the number of chromosomes is reduced by half through seperation
What are the stages of Meiosis 1 and what happens?
Prophase 1 - Chromatins shorten and pair up with homologous chromosomes forming a tetrad.
Metaphase 1 - Tetrads line up in center of cell.
Anaphase 1 - Tetrads break apart and move to opposite sides
Telophase 1 - Cell seperates into 2 daughter cells which have half the number of chromosomes
What are the stages of Meiosis 2 and what happens?
Prophase II - Pair of sister chromatins start towards center of cell.
Metaphase II - Chromatins line up in center of cell
Anaphase II - Chromatins are pulled to opposite sides by the spindles
Telophase II - Cells separate into 4 daughter cells
What information is found inside DNA?
- Guides the cell in making new proteins that determine all of our biological traits
- DNA gets passed from one generation to the next (copied)
- The key to all these functions is found in the molecular structure of DNA
What is the structure of DNA?
- Adenine
- Thymine
- Guanine
- Cytosine
At which phase does DNA replicate?
Occurs during interphase of mitosis or meiosis.
How does DNA replicate?
To replicate it unzips down the middle and each side can serve as a pattern or template for the other side
Cannot unzip all the way, instead it unzips a small area called a replication fork