Science Quiz Review (Bacteria, Viruses, Protists)

Vocabulary

1. virus - a tiny, non living particle that enters and then reproduces inside a living cell
2. host - an organism that a parasite lives with, in, or on, and provides a source of energy or a suitable environment for the parasite to live
3. parasite - an organism that benefits by living with, on, or in a host in a paratism interaction
4. vaccine - a substance used in a vaccination that consists of pathogens that have been weakened or killed but can still trigger the body to produce chemicals that destroy the pathogens
5. bacteria - single-celled organisms that lack a nucleus; prokaryotes, it has circular shaped DNA
6. cytoplasm - the thick fluid region located inside the cell membrane (in prokaryotes) or between the cell membrane and nucleus (in eukaryotes)
7. ribosome - a small grain-shaped organelle in the cytoplasm of a cell that produces proteins
8. flagellum - a long, whiplike structure that helps a cell move
9. celular respirsration - the process that releases energy by breaking down glucose and other food molecules in the presence of oxygen (krebs cycle)
   
10. binary fission - a form of asexual reproduction in which one cell divides, forming two identical cells
11. conjugation - a form of sexual reproduction in which a unicellular organism transfers some of its genetic material to another unicellular organism
12. endospore - a structure produced by prokaryotes, such as bacteria, in unfavorable conditions; a thick wall encloses the DNA and some of the cytoplasm
13. pasteurization - a process of heating food to a temperature that is high enough to kill most harmful bacteria without changing the taste of the food
14. decomposer - an organism that gets energy by breaking down wastes and dead organisms, and returns raw materials to the soil and water
15. protist - a eukaryotic organism that cannot be classified as an animal, plant, or fungus
16. protozoan - a unicellular, animal-like protist
17. pseudopod - a "false foot" or temporary bulge of cytoplasm used for feeding and movement in some protozoans
18. contractile vacuole - the cell structure that collects extra water from the cytoplasm and expels it from the cell
19. cilia - tiny, hairlike projections on the outside of cells that move in a wavelike manner
20. algae - plantlike protists
21. pigment - a colored chemical compound that absorbs light
22. spore - in bacteria, protists and fungi, a thick-walled, tiny cell capable of surviving unfavorable conditions and then growing into a new organism
23. fungus - a eukaryotic organism that has cell walls, uses spores to reproduce, and is a heterotroph that feeds by absorbing its food
24. hyphae - the branching, threadlike tubes that make up the bodies of multicellular fungi
25. fruiting body - the reproductive structure of a fungus that contains many hyphae and produces spores
26. budding - a form of asexual reproduction in which a new organism grows out of the body of a parent
27. lichen - the combination of a fungus and either an alga or an autotrophic bacterium that live together in a relationship that benefits both organisms

Bacteria

• Bacteria are organisms that have:
  • no nucleus (prokaryotes).
  • DNA (circular in shape).
• Not all bacteria cause disease, some are necessary for our own well-being. Some foods are prepared using bacteria:
  • yogurt
  • some cheeses
  • sausages
  • pickles
• Bacteria may live in many types of environments, even extreme ones.
• They are classified by their shape into categories:
  • coccus - round
  • bacilli - oval
  • spirilla - spiral
• Some examples of diseases caused by bacteria are:
  • dental cavities
  • tetanus (lockjaw)
  • botulism
  • strep throat
  • Tuberculosis
• Bacteria may reproduce every 20 minutes if they have the right conditions (temperature, moisture and food).
• Infections caused by bacteria are treated with antibiotics.
• Bacteria are also classified by the conditions or places where they may live:
  • Archaebacteria (Extreme Conditions)
  • Eubacteria
• Binary fission is the process used by them to reproduce.
• When bacteria are in danger, they develop an outer protective covering called endospore.

Viruses

• All viruses cause disease.
• They are not classified as organisms.
• The only life activity performed by them is reproduction.
• They are made of DNA or RNA (core) and an outer coat of protection.
• Some diseases caused by viruses are:
  • common cold
  • chicken pox
  • smallpox
  • Polio
  • cervical cancer
  • viral meningitis
  • Flu
• Viruses reproduce inside a host: living cell or organism. (Acts like a parasite)
• Viral diseases are prevented by inoculating people and animals with vaccines.
• When viruses reproduce they inject their genetic material into a cell. The genetic material makes copies of itself, is released and invades other cells to continue this process. Almost all viruses destroy the cells in which they multiply.
• The human body produces a substance called interferon to combat viral infections.
• Vaccines have weakened viruses to provoke the formation of antibodies.

Protists

• Organisms with characteristics of plants and animals are called protists. Animal like protists are called Protozoa.
• Protozoa, like Amoeba, move by pseudopods (extension of the cytoplasm) whilst Paramecium with cilia
• .
• Some examples of protists are:
• • Amoeba
  • Paramecia
  • Euglenoids
  • Diatoms
• Amoeba surround food and enclose it in a vacuole.

REMEMBER THIS IS ONLY A REVIEW, YOU MUST ALSO STUDY FROM YOUR TEXTBOOK AND NOTES.