3. Single-Celled Organisms
Single-Celled organisms are simple life-forms
They move, find food, grow, and reproduce
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4. One-Celled Organisms Amoebas – a kind of animal
One-celled organism with a nucleus
Live everywhere
Pond water, saltwater, animals, and humans!
Six kinds of amoebas are found in the human body
Amoebas have a cell membrane, cytoplasm, and a nucleus
They move by changing their shape
© LoveLearning 2014

5. One-Celled Organisms Algae – plant-like organisms
Live in water, moist places, under rocks
Among the oldest things on earth
Algae have a cell membrane, cytoplasm, nucleus, and chloroplasts
Algae produce most of the oxygen you breathe! More oxygen then all other plants combined
© LoveLearning 2014

6. One-celled organisms Bacteria – one celled organisms with no nucleus
The material that is usually in a nucleus can be found all over the cytoplasm instead
More bacteria on earth than any other kind of living thing
Some bacteria is helpful, and some is harmful
One handful of soil can contain billions of bacteria.
© LoveLearning 2014

7. How do single-celled organisms move?
Tail-like parts called flagella
Hairlike structures called cilia
Paramecium also use their cilia to get food
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8. Single-Celled Organisms
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10. A living thing that is too small to see without a microscope
Microorganism
A living thing that is too small to see without a microscope

11. Microorganisms Microorganisms live everywhere on Earth
Soil, air, water, humans
Bacteria make up the largest group of microorganisms
Other microorganisms:
Fungi, algae, protozoa (amoebas and paramecium)
© LoveLearning 2014

12. Harmful Microorganisms
Some harmful bacteria such as Salmonella and E. coli can make you sick
Found in raw chicken and meat, raw eggs, and other foods
If these foods touch other foods, the bacteria can spread
Cooking food kills this bacteria, but the bacteria will begin to grow again if the food is left out of the refrigerator for more than two hours
Strep throat is caused by harmful bacteria

13. Harmful Microorganisms
A virus is another microorganism that causes diseases
Smaller than bacteria
Viruses cause colds and diseases, and they change as they reproduce
Medicine that kills one virus cannot kill another virus
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14. Harmful Microorganisms
Fungus is another type of microorganism
Mold, yeast, mushrooms
Harmful mold and fungi can spread through crops and kill them
Also rot food and wood
Causes different types of skin diseases (athlete’s foot and ringworm)
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15. Helpful Microorganisms
We could not live without microorganisms!
Algae and plankton (microscopic plants and animals) float on the surface of the ocean
They feed tiny fish, bigger fish eat the tiny fish, etc.
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16. Helpful Microorganisms
1. Help provide us with other kinds of food
Bacteria turns milk into yogurt
1 gram of yogurt can contain 1 billion bacteria!
Bacteria produces cheese
Yeast makes bread, rolls, and cakes rise
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17. Helpful Microorganisms
2. Microorganisms help us digest our food
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18. Helpful Microorganisms
3. Microorganisms produce medicine
Penicillin is made from mold
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19. Helpful Microorganisms
4. Make dead things decay
Earth would otherwise be covered with a thick layer of dead plants and animals
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20. Living with Microorganisms
Wash hands often and cook food carefully
Antibiotics cure diseases caused by bacteria
Cannot cure diseases caused by fungi or viruses
Can kill both good and bad bacteria
Eating yogurt puts back good bacteria in your body
© LoveLearning 2014

21. Protect! Don’t Infect! http://safeshare.tv/w/bBRlgcprwH
© LoveLearning 2014

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