Terms and explanations

Genetics

Terms and Explanations Grouping Number 7

Meiosis

• Meiosis is a type of cellular reproduction that produces two haploid cells. (the chromosome number is divided in half )

• Meiosis contains nine phases {including interphase}

Interphase and Prophase l

• In Interphase, the cell replicates its chromosomes, and after this replication, the cell is left with two of the same sister chromatids , bonded together by a centromere. After Interphase is complete, Prophase l begins .ln Prophase l, the chromosomes bundle up and a spindle fiber is formed. Because of how closely bound the Chromosomes are , crossing over may occur.

Metaphase l and Anaphase l

• After the chromosomes condense and the spindle fiber forms in Prophase l, Metaphase l occurs. In Metaphase, the chromosome’s centromeres attach to spindle fibers that pull the chromosomes to the center of the cell. Then in Anaphase l , the Chromatids move to opposite sides of the cell . A key thing that does not occurs in meiosis is that the chromatids do not break in Anaphase l.

Telophase l and Prophase ll

In Telophase l, the spindle fiber in the cell are broken down, the Chromosomes unwind, and the cells cytoplasm is equally distributed between the two cells. Now, meiosis ll begins. In Prophase ll, both cells have Chromosomes that have bonded together to create coils.

Metaphase ll and Anaphase ll

After the Chromosomes bind together, they move to the center of the cell. In Anaphase ll. This is where the Chromosome clumps break and the equal parts move to the sides of the cell.

Telophase ll

Finally in Telophase ll, the meiosis cell reproduction process begins to slow down. The genetic material moves to four different parts of the cell and the cell begins to prepare to complete division.

The Eukaryotic Female Egg Cell

The female egg cell holds the beginning of new life. The female egg cells interior contains a nucleus, mitochondrion, cytoplasm, and a plasma membrane that supports the shape of the cell.

The Male Sperm Cell

The male sperm cell aids in the fertilization of the female egg cell in order to create a zygote.

Sexual Reproduction

Sexual Reproduction is completed when a male sex cell successfully fertilizes a female sex cell. Because the two sex cells, the female, and male have both gone though meiosis, the outcome of fertilization is stabilized. The two sex cell have half of there original Chromosomes due to meiosis, so when the two unite, you have a zygote with exactly half of each sex cell’s genetics.

Test Time!!!!!!!!

1. What is Meiosis?A. Cell destruction B. Cell Division C. Cell Reproduction D. A really hard word on the SAT that nobody knows

2. Is the female egg cell…A. a eukaryotic cell B. A Prokaryotic cellC. An alien cellD. Not a cell but an organelle

More Testing!!!!!

3. Does sexual reproduction form …A. A haploid Cell B. A Zygote

The Answers Were….C. Cell reproductionA. A eukaryotic cell

Thanks for Listening!!!

P.S. number 3’s answer is B. A Zygote