Exemplar for Internal Achievement Standard Science Level 1 This exemplar supports assessment against: Achievement Standard 90950 Investigate biological ideas relating to interactions between humans and micro-organisms An annotated exemplar is an extract of student evidence, with a commentary, to explain key aspects of the standard. It assists teachers to make assessment judgements at the grade boundaries. New Zealand Qualifications Authority To support internal assessment
Grade Boundary: Low Excellence 1. For Excellence, the student needs to investigate, comprehensively, biological ideas relating to interactions between humans and micro-organisms. This involves using findings and biological ideas to make significant links regarding the interactions between humans and micro-organisms, including the impacts of this knowledge on humans personal actions or everyday life. The student has provided a comprehensive explanation of the key biological ideas (1) for interactions between humans and one micro-organism (2). The personal action provided is explained in depth for bacteria (3). For a more secure Excellence, the student could provide more evidence about how the biological ideas about humans and bacteria have influenced people s personal or societal actions. For example, the student could explain that vaccinations affect bacterial diseases by disrupting life processes within the bacteria, and that this is useful for vaccination programmes because it can stop people catching a disease.
Pathogens and their effect on humans. Student 1: Low Excellence Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication rather than carrying out the processes they were designed to do. An example of this is the flu. The true flu, of which H1N1 is an example, is breathed into the lungs and throat of a person. If the immune system does not instantly destroy it then the flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the H1N1 virus. When the copying is complete the cells burst and induce an attack of coughing in the person so as the viral components are expelled at about 100kmhr -1. (2) The virus stops the cells taking oxygen to the blood as they now are manufacturing viral cells. If too many cells are compromised then the lungs break down and death can result. This is why flu viral diseases are dangerous. Antibiotics do not work on viruses. Doctors try to keep you alive until your immune system forms a antibody and then can destroy the flu virus. (1) Countries combat flu attacks by producing vaccination programmes and make these vaccinations available to people at risk including those with asthma and other lung diseases. The flu vaccination is passive vaccination so needs to be produced yearly. (3) OR Bacterial pathogens. Bacterial pathogens are microscopic single celled prokaryote organisms that can cause disease in humans. Not all bacteria cause disease and most bacteria are useful to humans. The harmful one can kill us. Salmonella is a bacterium that can cause food poisoning in humans. It comes from contaminated food, (2) especially chicken. When the bacterium is eaten it travels through the stomach and lodges in the intestine. Here it attaches to the intestine wall and uses our wastes as its food supply. In carrying out its living processes it excretes wastes into our intestine. These wastes are a neurotoxin to humans and stop our intestine functioning correctly. The large intestine cannot absorb water correctly and so we suffer diarrhoea This then causes us to lose fluids and for some people the fluid loss can lead to thickening of the blood and death. Bacteria can be treated with antibiotics. (1) One of the simplest ways to treat salmonella is to stop contamination of the bacteria. This can be done by covering food and storing in the fridge and especially by washing hands before a meal and after using the toilet. (3)
Grade Boundary: High Merit 2. For Merit, the student needs to investigate, in depth, biological ideas relating to interactions between humans and micro-organisms. This involves using findings and biological ideas to explain how, or why humans use, or are affected by microorganisms. The student has given an in-depth explanation of the key biological idea (1) and linked it to how humans and micro-organisms interact (2). To reach Excellence, the student could comprehensively explain the links between micro-organisms and humans, and give a personal or societal response showing how the key biological ideas surrounding pathogens can be controlled or minimised.
Pathogens and their effect on humans. Student 2: High Merit Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication rather than carrying out the processes they were designed to do. An example of this is the flu. The true flu, of which H1N1 is an example, is breathed into the lungs and throat of a person. If the immune system does not instantly destroy it then the flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the H1N1 virus. When the copying is complete the cells burst and induce an attack of coughing in the person so as the viral components are expelled at about 100kmhr -1. (2) The virus stops the cells taking oxygen to the blood as they now are manufacturing viral cells. If too many cells are compromised then the lungs break down and death can result. (1) OR Bacterial pathogens. Bacterial pathogens are microscopic single celled prokaryote organisms that can cause disease in humans. Not all bacteria cause disease and most bacteria are useful to humans. The harmful one can kill us. Salmonella is a bacterium that can cause food poisoning in humans. It comes from contaminated food, (2) especially chicken. When the bacterium is eaten it travels through the stomach and lodges in the intestine. Here it attaches to the intestine wall and uses our wastes as its food supply. In carrying out its living processes it excretes wastes into our intestine. These wastes are a neurotoxin to humans and stop our intestine functioning correctly. The large intestine cannot absorb water correctly and so we suffer diarrhoea. This then causes us to lose fluids and for some people the fluid loss can lead to thickening of the blood and death. Bacteria can be treated with antibiotics. (1)
Grade Boundary: Low Merit 3. For Merit, the student needs to investigate, in depth, biological ideas relating to interactions between humans and micro-organisms. This involves using findings and biological ideas to explain how or why humans use, or are affected by, microorganisms. The student has explained in depth the biological ideas (1). The effect of bacteria such as salmonella on humans is explained (2). For a more secure Merit, a more in-depth description of the way in which humans and micro-organisms interact could be provided. For example, the student could fully explain how the intestine functions and the way in which salmonella changes the intestine.
Pathogens and their effect on humans. Student 3: Low Merit Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication rather than carrying out the processes they were designed to do. An example of this is the flu. The true flu, of which H1N1 is an example, is breathed into the lungs and throat of a person. (2) If the immune system does not instantly destroy it then the flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the H1N1 virus. When the copying is complete the cells burst and induce an attack of coughing in the person so as the viral components are expelled at about 100kmhr -1. They can suspend in the air for up to 10 hours so infect long after you have gone. (1) OR Bacterial pathogens. Bacterial pathogens are microscopic single celled prokaryote organisms that can cause disease in humans. Not all bacteria cause disease and most bacteria are useful to humans. The harmful one can kill us. Salmonella is a bacterium that can cause food poisoning in humans. It comes from contaminated food, especially chicken. (2) When the bacterium is eaten it travels through the stomach and lodges in the intestine. Here it attaches to the intestine wall and uses our wastes as its food supply. In carrying out its living processes it excretes wastes into our intestine. The large intestine cannot absorb water correctly and so we suffer diarrhoea. (1)
Grade Boundary: High Achieved 4. For Achieved, the student needs to investigate biological ideas relating to interactions between humans and micro-organisms, by describing the biological ideas and describing the interactions between humans and two micro-organisms. The student has described the key biological ideas of excretion (1), and described interactions between humans and micro-organisms, viruses and bacteria (2). To reach Merit, the student could explain in depth how the biological ideas relate to an interaction between humans and micro-organisms, especially viruses. For example, the way viruses take over a cell and cause illness could be explained.
Pathogens and their effect on humans. Student 4: High Achieved Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication (2) rather than carrying out the processes they were designed to do. An example of this is the flu. The flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the flu virus. We cough the virus out when they are ripe. (1) AND Bacterial pathogens. Bacterial pathogens are microscopic single celled organisms that can cause disease in humans. Not all bacteria cause disease and most bacteria are useful to humans. (2) The harmful one can kill us. Salmonella is a bacterium that can cause food poisoning in humans. It comes from contaminated food, especially chicken. When the bacterium is eaten it travels through the stomach and lodges in the intestine. Here it attaches to the intestine wall and uses our wastes as its food supply. In carrying out its living processes it excretes wastes into our intestine. The large intestine cannot absorb water correctly and so we suffer runny poohs. [1]
Grade Boundary: Low Achieved 5. For Achieved, the student needs to investigate biological ideas relating to interactions between humans and micro-organisms, by describing the biological ideas and describing the interactions between humans and two micro-organisms. The student has described a biological idea (1) and described an interaction between humans and two micro-organisms: viruses and bacteria (2). For a more secure Achieved, the student could more clearly describe a key biological idea and relate it to human and micro-organism interactions. For example, the student could explain how pathogenic bacteria excrete wastes which are a poison to humans and this makes us sick: some poisons, like neurotoxins, can kill us.
Pathogens and their effect on humans. Student 5: Low Achieved Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication rather than carrying out the processes they were designed to do. An example of this is the flu. The flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the flu virus. (1) This can stop us breathing. (2) AND Bacterial pathogens. Bacterial pathogens are microscopic single celled organisms that can cause disease in humans. Not all bacteria cause disease and most bacteria are useful to humans. The harmful one can kill us. We can eat the good ones in yoghurt. Salmonella is a bacterium that can cause food poisoning in humans. Food poisoning makes you vomit. (2) Salmonella comes from contaminated food, especially chicken. When the bacterium is eaten it travels through the stomach and lodges in the intestine. Here it attaches to the intestine wall and uses our wastes as its food supply. (1)
Grade Boundary: High Not Achieved 6. For Achieved, the student needs to investigate biological ideas relating to interactions between humans and micro-organisms, by describing the biological ideas and describing the interactions between humans and two micro-organisms. The student has described an interaction between humans and one micro-organism (1). To reach Achieved, the student could clearly describe a biological idea, and relate it to interactions between humans and two micro-organisms. For example, the link between salmonella and toxins excreted and disease in humans could be described.
Pathogens and their effect on humans. Student 6: High Not Achieved Humans have suffered the effects of pathogens as long as there have been humans. Pathogens are micro-organisms that cause diseases in humans. Viral pathogens. Viral pathogens work by taking over cells and getting them to carry out viral cell replication rather than carrying out the processes they were designed to do. An example of this is the flu. The flu can enter the cell of the linings of the lungs and throat and take over the lung lining cells and force them to make multiple copies of the flu virus. This makes people sick. If you come into contact with someone who has the flu you can catch the virus by direct contact with their skin. (1) Bacteria: These also cause disease in humans and make us very sick. They do this by attacking us.