Meiosis is the process by which genetic information is passed from parents to offspring, and ultimately, is what allows a species to survive by way of evolution (due to genetic variation). In meiosis, the genetic information within the chromosomes of each individual parent cell is replicated and transferred to the subsequent generation through gametes (sex cells) during sexual reproduction. The gamete from each respective parent fuses its nucleus with that of the partner parent’s gamete to create a zygote. In effect, this brings half of the genetic information from each parent together to create a genetically different cell. Accumulatively, it can now be stated that the offspring will receive genes with genotypes (allele composition) that differ from those of its parents and, therefore will most likely display unique phenotypes (physical attributes) as well.
The actual mechanics of the meiotic process (cellular division and distribution of chromosomes) can be divided into two cycles that each consist of 4 phases.
1st Division:
1st Division begins with prophase- in which homologous chromosomes pair up and sort into chromatins in preparation for the “crossing over” process (crossing over
à + genetic variation)
prophase.gif
Metaphase- The chromosomes line up along the equator of the cell in a random sequence. (Independent assortment
à + genetic variation)
metaphase.gif
Anaphase- Homologous chromosomes move to opposite poles of the nucleus
anaphase.gif
Telophase- Nuclei form around each compilation of chromosomes; Cytokinesis: the cellular membrane “pinches” in toward the center of the cell to complete the separation of the two nuclei & membrane.
telophase.gif
After the first division, the process simply repeats itself ( with the chromatids as 'reactants' until 4 haploid cells are the resultant of the process of the diploid division. Whereas, mitosis only produces 2 cells. (haploid= one set of a chromosome, diploid= a pair/complete set)


Questions:
1. The point of contact between two gametes (the chiasmata) allows for what? What is does this increase?

2. If a human has 46 chromosomes, during reproduction, how many chromosomes does each parent contribute to its offspring?
a) 12 b) 11.5 c) 23 d) 46

3. How are gametes, diploids, haploids, and zygotes related to one another?

4. What is a major difference between meiosis and mitosis?
a) mitosis starts with 4 haploid cells, meiosis starts with 2 diploid cells b)mitosis only produces 2 cells, meiosis produces 4
c) mitosis deals with zygotes, meiosis involves gametes c) meiosis includes prophase, mitosis does not

Meiosis Crossword: http://www.variety-games.com/CW/Puzzles/11513184021731745067-puzzle.htm




















Question answers:
1. The chiasmata allows for the transfer of genetic material (mixing). This increases the potential for genetic variation.
2. Answer choice "C"

3. Gametes, Diploids, Gametes, and Haploids are related to eachother in that Gametes are haploids, and Zygotes are Diploids

4. Answer choice "B"
Crossword answers:
1. Diploid, 2. Chromatid, 3. Metaphase, 4. Forty(-)six, 5. Haploid, 6. Telophase, 7. Cytokinesis, 8. Twenty(-)three, 9. Zygote, 10. Gamete, 11. Anaphase, 12. Four, 13. Two, 14. Prophase



Sources:
www.biology-online.org
www.biology.arizona.edu
google images