Module 5 Lesson 1 - 5
Lesson 1 — Cell Division and Chromosomes
Lesson Summary
You have been introduced to the main types of cell reproduction: mitosis and meiosis. More details on each process are in future lessons. Each type is important and has a natural role in the cycle of life. Perhaps you are gaining an understanding of which areas scientists may concentrate on if they are to learn how to extend life. Certainly, at the heart of any new technology or procedure is the need to ensure that the proper number of chromosomes is maintained from one generation of cells to the next and that they contain all the correct genetic information.
During this lesson, you explored the following focusing questions:
- What kinds of cell division exist and when are they used?
- What are the structures that pass genetic information to the next generation and how are they observed?
Mitosis and meiosis are the main types of cellular division. In either type, DNA organized into chromosomes is the centre of proper cell replication. Humans have 22 pairs of autosomal chromosomes and a pair of sex chromosomes that determine sex. Together, all 46
chromosomes must be duplicated and then passed to each new daughter cell to enable those cells to perform their roles. Chromosomes can be stained and arranged in a karyotype from which scientists can determine the health and sex of a young
developing fetus.