Bio yr8 1st exam 2013 notes

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Simple, single celled. No true nucleus, just coils of DNA. Cell wall (not made of cellulose) and cell membrane. Small, approx 1/1,000mm (=1μm)

Multiply quickly and release poison (toxins) which attack cells. These toxins reach dangerous levels when there are a lot of bacteria present.

Used

Used to make yoghurt, cheese soap powder. Aids digestion.

Causes food poisoning, tetanus, tuberculosis, tonsilitis.

CAN be treated by antibiotics

Bacteria

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Virus

A strand of genetic info (DNA/RNA) surrounded by a protein coat. No Nucleus. Non living, can only reproduce by invading other cells (Parasitic). Very small, approx 1/1000000mm (=1nm)

Viruses inject there DNA into cells to make more viruses. Eventually cells become so full of viruses they burst.

Used in genetic engineering. Some kill bacteria.

Chickenpox, aids, common cold, influenza

CAN NOT be treated by aintibiotics

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Have Nuclei, and lack chlorophyll. Multi-cellular fungi are made up of tubular threads called hyphae. A dense mat of hyphae, called a mycelium, make up the body of the fungus. Aerial hyphae support the spores; feeding hyphae secrete digestive enzymes and then absorb soluble molecules.

Grow longer and release poisons which attack cells.

Used as a source of antibiotics . Used in the production of beer/bread.

Athletes foot, ringworm.

CAN NOT be treated by antibiotics.

Microbes type