Unit C Cell Division, Genetics, and Molecular Biology

Introduction

From one generation to the next, from a single cell bacteria to people, we are all part of a competition to produce more of our own species. How can one generation ensure its best is passed to the next generation? Should we have the power to decide exactly what the next generation will look like? This unit is about the cycle of life. From the secrets of cellular reproduction to the story of why you may have your grandmother's nose, this unit explores how our biology is caught in an increasingly complex drive to survive.

In Unit A, you examined how the human body used the nervous and endocrine systems to maintain homeostasis. In Unit B, you examined the human reproductive systems.


Unit C has three modules:

Module 5 examines reproduction at the cellular level. Individual cells, similar to humans and all other multi-cellular organisms, must ensure the next generation has all it needs to survive and excel. You will learn how the cell life cycle progresses naturally. You will examine how cells copy their instructions for the next generation. You will discover how somatic cells divide to form new, complete cells and how gametes are formed from germ cells. Each gamete must find another gamete with which to join to become a new, whole organism. You will compare these methods of reproduction, examining their advantages and limitations.

Module 6 is intended to help you understand that the instructions copied by cells during the cell cycle are the codes for traits observed in organisms. You will look more closely at how an organism passes its traits to the next generation. As you consider these patterns of inheritance, you will learn about the work of Gregor Mendel and his contribution to the understanding of genetics today. You will practise using predictive tools to allow you to understand and explain the movement of a disease or condition through a family pedigree.

 
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Module 7 examines the molecular basis for these traits in the cell, and you will gain an understanding of how cells express these traits through protein synthesis. As you examine the molecules present in cells, you will reflect on how mutation can change the intended expression of  genetically inherited traits. Genetic change can result in disease. It can also result in enhanced abilities, and it can be the basis of evolution as explored in Unit D.

The major concepts you will explore and the skills you will develop in this unit are the following:

  • Explain the rules and steps involved in mitosis and meiosis that regulate the transmission of genetic information from one generation to the next.

  • Describe the similarities and differences that exist in mitosis and meiosis that allow for growth, healing, and reproduction of organisms.

  • Hypothesize how the understanding of the molecular nature of genes and DNA can help explain the transmission of traits as well as how mutation at the molecular level results in changed proteins.

  • Analyze how the knowledge of the molecular nature of genes and DNA has led to new biotechnology and treatment of genetic disorders.


Think about the following questions as you complete this unit:

  • What are the cellular processes that an organism uses for growth, healing, and reproduction to ensure the survival of its species?

  • What regulates the transmission of genetic information from one generation to the next?

  • How is DNA responsible for the production of proteins?

  • How has the molecular knowledge of genes and DNA led to new biotechnology and the treatment of genetic disorders?