In an effort to study in advance for my biology test on Friday I've been completing the objectives for this unit in my objective notebook
since Monday. As most of the people reading this blog probably know, objective books are horrible. But, it actually makes a lot of sense to write out all of the objectives before you take the test. Biology (especially IB Biology) requires memorization of biological processes. To be honest, I'm not very good at memorizing things. I can't even remember what I ate for breakfast! It has become impossible for me to memorize anything without writing it down a million times. Unfortunately, this is a tedious and annoying process. I definitely lose a few crucial hours of sleep studying for classes like Biology where there is SO
much information to learn at once.
Writing things down in my objective notebook has helped me study for biology. And now I'd like to try something else! So this week, I've decided to explain the process of meiosis
. Hopefully this will help me, and you, study for the upcoming test!
|Stages of Meiosis|
So what's the purpose of meiosis? WELLLL according to IB, meiosis is a reduction division of a diploid nucleus to form haploid nuclei
. Say what? Ok, let's decode that in real english. Meiosis is similar to mitosis because it involves cell division. Meiosis uses two cell divisions to make gametes or sex cells. These gametes have half the number of chromosomes than cells produced by mitosis. In human gametes, there are 23 chromosomes.
The process of meiosis is like a pattern or cycle. There are two cell divisions, but within each division the same key steps occur. The two cell divisions of meiosis are labeled Meiosis I and Meiosis II. Meiosis I includes Interphase I, Prophase I, Metaphase I, Anaphase I, and Telophase I. Meiosis I produces 2 cells with half of the genetic information as the original cell. A second division will be required for sister chromatids to split.
Meiosis I is followed by Meiosis II. Meiosis II consists of the same stages as Meiosis I with the stages in the same order. The purpose of Meiosis II is to produce cells with 1 chromosomes from each from each of the original homologous pairs. Each of the new cells produced will be unique. These cells will be able to mature into eggs or sperm in the process of gametogenesis.
So why is meiosis important? Meiosis leads to genetic variation in organisms. Genetic variation is especially important because it is one of the basic mechanisms of evolutionary change. As IB wants us to know, meiosis results in an effectively infinite genetic variety in gametes
. Meiosis produces the unique gametes that are able to become zygotes and then full organisms. Within these organisms, the species with the strongest traits for survival are more likely to survive and pass on their genes or mate.
That was actually really helpful for me to organize all my thoughts this way! Hopefully I can retain this information for the test and beyond. I still have more studying to do!
Meiosis animation my group created for Biology!