• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Introduction to bacteria

Extracts from this document...


Introduction to bacteria: Bacteria, one-celled organisms visible only through a microscope. Bacteria live all around us and within us. The air is filled with bacteria, and they have even entered outer space in spacecraft. Bacteria live in the deepest parts of the ocean and deep within the earth. They are in the soil, in our food, and on plants and animals. Even our bodies are home to many different kinds of bacteria. Our lives are closely intertwined with theirs, and the health of our planet depends very much on their activities. Bacteria cells are so small that scientists measure them in units called micrometers. One micrometer equals a millionth of a meter, and an average bacterium is about one micrometer long. Hundreds of thousands of bacteria would fit on a rounded dot made by a pencil. Bacteria lack a true nucleus, a feature that distinguishes them from plant and animal cells. In plants and animals the saclike nucleus carries genetic material in the form of D.N.A . bacteria also have D.N.A but it floats within the cell, usually in a loop or a coil. A tough but resilient protective shell surrounds the bacterial cell. Bacteria inhabited the Earth long before human beings or other living things appeared. ...read more.


NITROGEN FIXATION: Bacteria play a key role in making soil fertile. They convert nitrogen in Earth's atmosphere into the nitrogen compound ammonia, which plants need to grow. Bacteria are the only organisms able to carry out this biochemical process known as Nitrogen Fixation. The bacteria able to fix atmospheric nitrogen usually live in association with plants, often integrated into the plant tissue. These are friendly bacteria BACTERIA IN FOOD: Most people would think bacteria in or on food can only be harmful. True, food poisoning caused by bacteria and their products is a serious problem, however, certain bacteria are safe in food, and are required for the desired taste and texture. Bacteria are commonly used in dairy products. The good bacteria in dairy products are introduced at a very simple level here. Sour cream and cr�me fresh are both the products of cream after bacteria were allowed to grow in it. The difference in flavour, texture and behaviour all result from the differences in bacteria required to produce the two products. Buttermilk is low in fat, cheese comes in many variations. Yogurt is probably one of the oldest forms of fermented milk. It is not dangerous to eat food containing bacteria. ...read more.


Chemosynthesis occurs in vents at the bottom of the ocean, where light is unavailable for photosynthesis but hydrogen sulphide gas bubbles up from below Earth's crust. Life can develop around these vents because bacteria use the hydrogen sulphide gas in changing carbon dioxide into organic nutrients. The hydrogen sulphide gas coming up from Earth's mantle is extremely hot, but bacteria in these vent communities are adapted to the high temperatures. MY CONCLUSION: When all facts are considered, bacteria are more helpful than harmful. Humans have wide variety of users, such as ; making cheese and butter, decomposing waste in sewage plants, antibiotics. Bacteria is also a best friend to our ocean, plants, animals, and air, it loves all the elements of our environment and is good to them! Bacteria have been able to survive without us, but we could never live without them! Therefore I would consider bacteria to be a friend! Reference: http:/Encarta.msn.com/encyclopedia/bateria.html Reference: http:/www.ncbi.nlm.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uid Reference: New York Times Science Q & A Reference: Cow & gate Premium baby formula (Probiotic) Reference: Biochemistry, Martin Carr and Bob Cordell, 1992, London Reference: Understanding Biology for advanced level, fourth edition, Glenn and Susan Toole, 1987, 1991, 1995, 1999, Stanley Thornes (publishers) London Reference: A-level Biology, W D Phillips and T J Chilton, 1989-2001, Oxford University Print, Oxford. ?? ?? ?? ?? 02/05/2007 BIOLOGY ESSAY JANE DONNELLY BACTERIA FRIEND OR FOE? I ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Living Things in their Environment section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Living Things in their Environment essays

  1. Marked by a teacher

    The effects of disinfectants and antibacterial soap on bacterial growth

    5 star(s)

    On the second control plate, there was one white circular colony on the peripheral area of the agar, but otherwise, no bacterial growth was present. Contamination can be explained by the various sources of error mentioned in the following discussion.

  2. Marked by a teacher

    A2 Biology Coursework -Investigation into the effect of different concentrations of antibiotics on the ...

    4 star(s)

    Difference2 (D2) 100.00% 0.01 11 1.5 9.5 90.25 90.00% 0.01 10 1.5 8.5 72.25 80.00% 0.02 9 3 6 36 70.00% 0.06 8 6.5 1.5 2.25 60.00% 0.06 7 6.5 0.5 0.25 50.00% 0.05 6 4 2 4 40.00% 0.06 5 6.5 -1.5 2.25 30.00% 0.06 4 6.5 -2.5 6.25

  1. Marked by a teacher

    Biology Recycling

    4 star(s)

    The Con's of not Recycling The drawbacks of not recycling are:- * Resources will once run out if tipped. * CO2 levels will increase (a Bigger 'Carbon Footprint') * Landfill space will run out which will lead to trash being tipped outside of landfill space.

  2. Investigation - Examination of bacterial sensitivity on antibiotics.

    T 1.2 0 0 0 0.3 TM 0 0 0 0 0 E 0 0 0 0 0 FC 0 0 0 0 0 SMX 0 0 0 0 0 (iii) Micrococcus luteus. Antibiotic 1st diameter (mm)

  1. Investigating the effect of four antibiotic agents on gram positive and gram negative bacteria.

    The two natural penicillin's, Penicillin G and Penicillin V, were extremely useful in treating the wounded during the Second World War. It was also discovered that removing the acyl group and then adding new acyl groups to give new properties to the antibiotic could modify penicillins.

  2. Extended Experimental Investigation - Natural Antibiotics

    Albus Lime/Garlic [1:1] 11 S. Albus Lemon/Lime/Garlic [1:1:1] (again) 12 *The radius of sterilization refers to the average radius from the confetti stop that the antiseptic has effectively sterilized the agar so that it is impossible for the bacteria to survive. This graph documents the measures of effectiveness for each antibiotic tested.

  1. Culturing Bacteria.

    wishes to separate out the individual colonies of different species of bacteria. Liquid cultures can also be grown using essentially the same method, but instead of the inoculating loop being run over agar, it is swirled in a nutrient broth solution.

  2. The comparison of bacterial content in a range of milks.

    I would also predict that the Whole pasteurized, and the semi-skimmed pasteurized will have similar amounts of bacteria to start with, because both have undergone the pasteurization process, but the amount of bacteria in the whole milk will be increasing at a faster rate due to the fact that there are more fat globules present.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work