Biology Notes
HSC Biology
9.4 The Search for Better Health
9.4-6
You have been looking at the different types of diseases that affect the human body and the natural defence mechanisms that maintain health. In this last part of the module you will look at how increased understanding has led to the development of a wide range of strategies to prevent and control disease. In this part you will have the opportunity to: • discuss the role of quarantine in preventing the spread of disease and plants and animals into Australia and across regions of Australia. • explain how one of the following strategies has controlled and/or prevented disease: - public health programs - pesticides - genetic engineering to produce disease resistant plants and animals • perform an investigation to examine plant shoots and leaves and gather first-hand information of evidence of pathogens and insect pests • process and analyse information from secondary sources to evaluate the effectiveness of quarantine in preventing the spread of plant and animal disease into Australia and across regions of Australia. • gather and process information and use available evidence to discuss the changing methods of dealing with plant and animal diseases, including the shift in emphasis from treatment and control to management or prevention of disease.
HSC Biology 9.4-6 Page 1
Investigating plant diseases As you learned in an earlier Study Guide, many different organisms can cause disease in plants, including bacteria, viruses, fungi, nematodes and insects. All parts of a plant may be attacked, including roots, stems, leaves and flowers. It is sometimes difficult to identify the causes of plant diseases but black spots caused by fungi are usually easier to identify and viruses may cause leaf deformities or patchy discolouration on leaves or flowers. It is usually easy to identify damage to plants caused by insect attack, too. The edges of leaves may be chewed by caterpillars, there may be white tracks caused
9.4 The Search for Better Health
9.4-6
You have been looking at the different types of diseases that affect the human body and the natural defence mechanisms that maintain health. In this last part of the module you will look at how increased understanding has led to the development of a wide range of strategies to prevent and control disease. In this part you will have the opportunity to: • discuss the role of quarantine in preventing the spread of disease and plants and animals into Australia and across regions of Australia. • explain how one of the following strategies has controlled and/or prevented disease: - public health programs - pesticides - genetic engineering to produce disease resistant plants and animals • perform an investigation to examine plant shoots and leaves and gather first-hand information of evidence of pathogens and insect pests • process and analyse information from secondary sources to evaluate the effectiveness of quarantine in preventing the spread of plant and animal disease into Australia and across regions of Australia. • gather and process information and use available evidence to discuss the changing methods of dealing with plant and animal diseases, including the shift in emphasis from treatment and control to management or prevention of disease.
HSC Biology 9.4-6 Page 1
Investigating plant diseases As you learned in an earlier Study Guide, many different organisms can cause disease in plants, including bacteria, viruses, fungi, nematodes and insects. All parts of a plant may be attacked, including roots, stems, leaves and flowers. It is sometimes difficult to identify the causes of plant diseases but black spots caused by fungi are usually easier to identify and viruses may cause leaf deformities or patchy discolouration on leaves or flowers. It is usually easy to identify damage to plants caused by insect attack, too. The edges of leaves may be chewed by caterpillars, there may be white tracks caused