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Description of some biological concepts

1. There are three differences between the accomplishments of mitosis and the accomplishments of meiosis. One of these differences is fairly trivial: the other two are very important. What these three differences? For each of the differences, make sure that you clearly explain what it is that mitosis does and what it is that meiosis does.

2. You know the meaning of the work "diploid" Bananas are triploid. What do you suppose that means? Wheat is a heaploid. What does that mean?

3. This question explores the meaning of dominance. Please answer both parts. It is often said that certain traits "skip generations". What kind of trait might do this? Can brown eyes skip generations? What about blue eyes? Why.

4. Human beings can suffer from a large variety of genetic ailments. While many of these are relatively benign - or at least, mild enough that the sufferers can live with them for a lifetime - some are not. Some are always lethal. One lethal genetic disorder it Tay Sach disease. This Disease is always fatal: sufferers die before the age of five, and thus never reproduce. Tay Sach disease is caused by an autosomal recessive allele. Why doesn't a disease like Tay Sachs simply disappear from the species, since it is completely selected against (i.e. no sufferer ever has children)?

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As a cell increases in size, the volume increases at a faster rate than the surface area. Since a cell depends
on the surface for obtaining food and oxygen, the smaller the surface area to cell volume ratio becomes, the harder
it is for a cell to survive. Eventually the cell will be unable to obtain enough food and oxygen to support the
interior. In order to overcome this problem, the cell will divide into two, thus increasing the surface area/volume
ratio for each of the two daughter cells. There are two types of cell division in eukaryotes, MITOSIS and MEIOSIS,
and they have very different functions.
Ensuring that each daughter gets all the necessary genetic information that is contained within the nucleus is
very important. If either cell lacks essential information it will die;therefore it is vital that the distribution be exact.
This is achieved by a process known as mitosis. In this daughter cells will have the same number of chromosomes as
the parent.
Mitosis is divided up into five phases: interphase, prophase, metaphase, anaphase and telophase.

In sexual reproduction, two individuals each donate a specialized cell (gamete); the gametes fuse to form
a new single cell, the zygote. At this time in the life cycle of the adult organism, during the production of gametes
(egg and sperm), the number of chromosomes must be halved. Later on fusion, the number gets restored.
Mitosis, is intended to keep the number of chromosomes constant, and therefore cannot be used to reduce ...

Solution Summary

More than 900 words explanation of the asked concepts and questions. A good reference and guide.

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