Module 5 Cell Division
Lesson 3.5.1
Lesson 1—Cell Division and Chromosomes
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Get Focused
Life is about cycles. At the cellular level, the cell cycle involves reproducing identical cells through mitosis. At the organism level, mitosis can once again produce identical cells—this time their offspring. Organisms with variations are produced through meiosis, another type of cell cycle. The similarities and differences in the offspring can be explained by examining chromosomes.
As far as the human race is concerned, genetic material from both the male and female are necessary to create a new human being. How the child ends up with the characteristics of either parent continues the cycle of cellular division and reproduction. Our reproductive cycle is a strictly sexual affair.
Sometimes in nature, reproduction can be rather diversified and unique. Aphids, for example, all hatch out of their eggs female. Perhaps more alarming is the fact that they already have live nymph aphids developing inside them. These too will be born female and pregnant. In little time, aphids can dominate a crop and cause serious economic damage. This sounds like a winning reproductive strategy. Why have males anyway? However, the aphid’s tale is not over. In the fall, males will suddenly be born. They will mate with females and produce eggs that will hatch over winter. Why the change? Why would aphids go through all the trouble of changing strategies just when conditions are getting tougher?
In this lesson you will identify the types of cellular division and reproduction, and understand their functions and purpose. You will be able to recognize the structures within the cell that carry genetic information. You will learn about the significance of chromosome number in cells, and learn how to read a picture of human chromosomes.
In this lesson the following focusing questions will be examined
- 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?
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This lesson will take approximately 60 minutes to complete.
Module 5: Lesson 1 Assignment
Once you have complete all learning activities for this lesson, you can complete the online assignment.
The other questions and activities in this lesson are not marked by the teacher; however, you should still attempt all of the work offered here. They are designed to help you review important information and build key concepts that may be applied in future lessons.
Here is a tutorial video for this lesson that you can watch if it suits your learning style. Bio30 tut#3.5.1 Cell Division