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Mitosis, Meiosis, Chromosome Abnormalities and Genetic Tests

1. How does mitosis differ from meiosis? When do they occur in the body and what is their purpose?
2. Name and briefly describe 4 different chromosome abnormalities that can occur. (Use actual conditions and describe how they affect the carriers).
3. A child is born with attached ear lobes. His parents have free ear lobes. What is the genotype of all persons mentioned?
4. In your own words, describe the process of protein synthesis, starting with the DNA, stored in the nulceus, and ending with the completed protein. Be sure to mention the terms code, codon, anticodon, mRNA, tRNA, amino acids and ribosomes in your answer.
5. Briefly compare and contrast the three methods of obtaining fetal cells for testing.
6. You and your partner have decided to have kids. What type of testing, if any, would you have done on the fetus? Describe three tests, how they are performed, their pros and cons, and whether you would have them done and why.

Solution Preview

Mitosis and meiosis describe two processes that certain cells go through. Both processes can be said to increase the total number of cells - mitosis creates a replicate of the original cell. Meiosis creates two cells from one cell as well, but splits the genetic material from the original cell into those two new cells. Cells undergo mitosis to proliferate - that is, to grow or repair. Cells undergo meiosis to develop what are known as germ cells, which are used as counterparts to another sex's germ cells for the purpose of reproduction. The haploid state of germ cells, containing half the genetic material of normal cells, allows the mixing of genetic material when two germ cells from a male and a female meet (sperm and egg). Mitosis occurs in most but not all tissues of the body whereas meiosis is specific to germ cells; therefore meiosis only occurs in the reproductive organs.

Chromosome abnormalities are many and numerous. The more common would include Down's syndrome (trisomy 23), which is the existence of part of or the entire extra chromosome 21. Issues with expression from this extra copy results in impaired cognitive abilities, among other issues. Another is polycystic kidney disease (PKD), which is usually ...

Solution Summary

Brief discussion on the following topics: differences between mitosis and meiosis, examples of chromosomal abnormalities (Down's, PKD, Tay-Sach's, melanoma), transcription and translation, autosomal dominant and autosomal recessive, fetal testing (amniocentesis and chorion villi sampling).