Biology Unit 2: How does Inheritance Impact Diversity?

Prerequisites

Students are advised to complete Biology Unit 1 before undertaking Biology Unit 2.

Course Description

This unit focusses on cell reproduction and the transmission of biological information from generation to generation. Students learn that all cells are derived from pre-existing cells through the cell cycle. They examine the process of DNA replication and compare cell division in both prokaryotic and eukaryotic organisms. Students explore the mechanisms of asexual and sexual reproductive strategies, and consider the advantages and disadvantages of these two types of reproduction. The role of stem cells in the differentiation, growth, repair and replacement of cells in humans is examined, and their potential use in medical therapies is considered.

Students use chromosome theory and terminology from classical genetics to explain the inheritance of characteristics, analyse patterns of inheritance, interpret pedigree charts and predict outcomes of genetic crosses. They explore the relationship between genes, the environment and the regulation of genes in giving rise to phenotypes. They consider the role of genetic knowledge in decision-making about the inheritance of autosomal dominant, autosomal recessive and sex-linked genetic conditions. In this context the uses of genetic screening and its social and ethical issues are examined.

Students also undertake a student-directed research investigation into, and communication of, an issue related to genetics and/or reproductive science.

Areas of Study

How does inheritance impact on diversity?

Students consider the need for the cells of multicellular organisms to multiply for growth, repair and replacement. They examine the main events of the cell cycle in prokaryotic and eukaryotic cells. Students become familiar with the key events in the phases of the cell cycle, and focus on the importance of the processes involved in a cell’s preparation for cell division. Students investigate and use visualisations and modelling to describe the characteristics of each of the phases in mitosis. Cytokinesis is explained for both plant and animal cells. Students describe the production of gametes in sexual reproduction through the key events in meiosis and explain the differences between asexual and sexual reproduction in terms of the genetic makeup of daughter cells. Students consider the role and nature of stem cells, their differentiation and the consequences for human prenatal development and their potential use to treat injury and disease.

How is inheritance explained?

Students build on their understanding of the nature of genes and the use of genetic language to read and interpret patterns of inheritance and predict outcomes of genetic crosses. They gain an understanding that a characteristic or trait can be due solely to one gene and its alleles, or due to many genes acting together, or is the outcome of genes interacting with external environmental or epigenetic factors. Students apply their genetic knowledge to consider the social and ethical implications of genetic applications in society including genetic screening and decision-making regarding the inheritance of autosomal and sex-linked conditions.

How do inherited adaptations impact on diversity?

Students analyse the advantages and disadvantages of sexual and asexual reproduction and investigate the use and application of reproductive technologies. They also explore the biological importance of diversity. Students explore the interdependancies between species. They consider the contributions of Aboriginal and Torres Strait Islander peoples in understanding adapations and interdependancies between species.

How do Humans use science to explore and communicate contemporary bioethical issues?

In this area of study students explore a contemporary bioethical issue relating to the application of genetic knowledge, reporductive science, inheritance or adaptataions beneficial for survivial.

Assessment

Outcomes	Assessment Tasks
Outcomes	(school-assessed coursework)
Compare the advantages and disadvantages of asexual and sexual reproduction, explain how changes within the cell cycle may have an impact on cellular or tissue system function and identify the role of stem cells in cell growth and cell differentiation and in medical therapies.	Tasks are selected by the teacher from the following: A report of a fieldwork activity. Annotations of a practical work folio of activities or investigations. A bioinformatics exercise. Media response. Data analysis. Problem solving involving biological concepts, skills and/or issues. A reflective learning journal/blog related to selected activities or in response to an issue. A test comprising multiple choice and/or short answer and/or extended response.
Apply an understanding of genetics to describe patterns of inheritance, analyse pedigree charts, predict outcomes of genetic crosses and identify the implications of the uses of genetic screening and decision making related to inheritance.
A response to an investigation into a bioethical issue relating to genetics or reproductive science or adaptations beneficial for survival.	The assessment task includes a report on an investigation an appropriate format, for example, digital presentation, oral communication or written report.

Overall Final Assessment

End of Semester Examination – 1.5 hours.