Post by Admin on Oct 6, 2016 9:36:47 GMT
Micro-organisms are small living things. There are three types of micro-organisms: viruses, bacteria and fungi.
Viruses are: the smallest micro-organisms, unable to reproduce by themselves (they use other cells to produce new viruses), parasites and the causes of diseases such as colds, flu, measles, mumps and AIDS. A parasite is a living thing that gets its food from another living thing.
Bacteria: are larger than viruses, are visible only under a microscope, need food, water, a suitable temperature and pH to grow, reproduce asexually, causes diseases such as TB, pneumonia, sore throats, tetanus and food poisoning and can be parasites or saprophytes. A saprophyte is a living thing that gets its food from dead sources. Advantages of bacteria is that they make foods such as cheese, butter and yoghurt and decay dead plants and animals (releasing minerals into the soil to be re-used by plants.) Disadvantages of bacteria are that they cause disease and destroy foods.
Antibiotics are chemicals made by micro-organisms that kill or prevent the growth of bacteria.
Fungi are: simple plants that do not contain chlorophyll, not green, not able to make their own food, single celled or made of underground threads. Advantages of fungi are that it can be eaten and used to make alcohol. Disadvantages of fungi are the it causes diseases such as athlete's foot and ringworm and causes food to rot.
Biotechnology is the use of living things or parts of living things to make useful products. Biotechnology used plants, animals, bacteria, yeasts and enzymes to produce useful products. Industrial uses of biotechnology include yeast, making alcohol in breweries and bacteria, making stain-removing enzymes for use in washing powders. Medical uses of biotechnology include bacteria and fungi, making antibiotics and bacteria and yeast being treated so that they can produce products such as human hormones, antibodies or drugs.
To investigate the presence of micro-organisms in air and soil:
- Obtain 3 sterile petri dishes, A B C, containing nutrient agar.
- Remove the lid from Dish A to allow micro-organisms from the air to land on the agar.
- Sprinkle a small sample of soil over the agar in Dish B.
- Do not open Dish C as this dish acts as a control.
- Close all the dishes, seal them with tape and label them on the undersides.
- Place the 3 dishes in a warm room or incubator for a few days.
- Dish A may have round, shiny patches of bacteria growing on the agar or there may be patches of fluffy growth which is caused by fungi.
- Dish B may be similar to Dish A.
- Dish C should have no growth on the surface of the agar.
Viruses are: the smallest micro-organisms, unable to reproduce by themselves (they use other cells to produce new viruses), parasites and the causes of diseases such as colds, flu, measles, mumps and AIDS. A parasite is a living thing that gets its food from another living thing.
Bacteria: are larger than viruses, are visible only under a microscope, need food, water, a suitable temperature and pH to grow, reproduce asexually, causes diseases such as TB, pneumonia, sore throats, tetanus and food poisoning and can be parasites or saprophytes. A saprophyte is a living thing that gets its food from dead sources. Advantages of bacteria is that they make foods such as cheese, butter and yoghurt and decay dead plants and animals (releasing minerals into the soil to be re-used by plants.) Disadvantages of bacteria are that they cause disease and destroy foods.
Antibiotics are chemicals made by micro-organisms that kill or prevent the growth of bacteria.
Fungi are: simple plants that do not contain chlorophyll, not green, not able to make their own food, single celled or made of underground threads. Advantages of fungi are that it can be eaten and used to make alcohol. Disadvantages of fungi are the it causes diseases such as athlete's foot and ringworm and causes food to rot.
Biotechnology is the use of living things or parts of living things to make useful products. Biotechnology used plants, animals, bacteria, yeasts and enzymes to produce useful products. Industrial uses of biotechnology include yeast, making alcohol in breweries and bacteria, making stain-removing enzymes for use in washing powders. Medical uses of biotechnology include bacteria and fungi, making antibiotics and bacteria and yeast being treated so that they can produce products such as human hormones, antibodies or drugs.
To investigate the presence of micro-organisms in air and soil:
- Obtain 3 sterile petri dishes, A B C, containing nutrient agar.
- Remove the lid from Dish A to allow micro-organisms from the air to land on the agar.
- Sprinkle a small sample of soil over the agar in Dish B.
- Do not open Dish C as this dish acts as a control.
- Close all the dishes, seal them with tape and label them on the undersides.
- Place the 3 dishes in a warm room or incubator for a few days.
- Dish A may have round, shiny patches of bacteria growing on the agar or there may be patches of fluffy growth which is caused by fungi.
- Dish B may be similar to Dish A.
- Dish C should have no growth on the surface of the agar.