Life Science (G)

4th Quarter Exam Study Guide ANSWER KEY

1. Define the following terms:bacteria, gene therapy, antibiotic, bioremediation, pathogens, immune system, antigens, antibody

bacteria – one-celled organisms without membrane-bound organelles

gene therapy – uses viruses to replace defective hereditary material in cells

antibiotic – a drug used to kill bacteria

bioremediation – uses bacteria to break down wastes and pollutants into simple harmless compounds

pathogens –organisms that produce disease

immune system – group of defenses that your body has to fight disease

antigens – proteins and chemicals foreign to your body

antibody – substances made in response to a specific antigen

2. Describe some ways in which bacteria is used for beneficial purposes.

Farming – use nitrogen-fixing bacteria, also use bacteria for bio-remediation

Medical Industry – used to make antibiotics

Food Industry – used to make dairy products, sauerkraut, vinegar, pickles, olives, and soy sauce

3. Draw and name the different shapes of bacteria.

Coccus – sphere shaped

Bacillus – rod shaped

Spirillum – spiral shaped

4. Give some examples of diseases for which there is a vaccine available.

Polio, rabies, measles, mumps, chicken pox, polio, smallpox. Etc.

5. Give some examples of diseases for which there is NO vaccine available.

Common cold, HIV

6. What types of organisms cause infectious diseases?

Viruses, fungi, bacteria

7. How are infectious diseases spread?

Can be spread through water, air, or in food

8. Describe how viruses reproduce.

- a virus attaches to the surface of a cell

- the hereditary material of the virus is injected into the cell

- the hereditary material directs the cell to make new virus particles

- new viruses form inside the host cell

- the host cell bursts open and releases the new viruses

9. What are some of your body’s first-lines of defense against infectious diseases?

Your skin and sweat; cilia and mucus in your respiratory system; enzymes in mucus, stomach, pancreas, and liver; acid in your stomach

10. Louis Pasture, Joseph Lister, and Robert Koch are all known for their work in the field infectious disease. Describe an important discovery of each scientist.

Louis Pasture – first to discover that bacteria can cause disease

Joseph Lister – discovered the relationship between cleanliness and infection rate

Robert Koch – developed a series of methods for identifying which organism was the cause of a particular disease

11. How do antibodies work?

Antibodies attach to an antigen and make them useless

12. What is the difference between active and passive immunity?

Active immunity – your own body produces antibodies in response to a specific antigen; develops when a pathogen (germ) invades your body or when you receive a vaccine; active immunity lasts a long time

Passive immunity – antibodies produced by another animal are introduced into your body; example: when a baby receives antibodies from its mother’s milk; passive immunity only lasts a short time

13. Define: vascular plants, nonvascular plants, rhizoids, liverworts, cuticle, phloem, xylem, cambium

vascular plants – plants that have tubelike structures for transporting substances

nonvascular plants – plant that absorbs water and other substances directly through its cell walls instead of through tubelike structures

rhizoids – rootlike filaments made up of a few long cells

liverworts – non-vascular plant whose name means “herb for the liver”

cuticle – a waxy, protective layer on leaves of plants

phloem – vessels that move food from leaves to other plant parts

xylem – vessels that transport substances from the roots to other parts of the plant

cambium –tissue that produces new xylem and phloem cells

14. Give some examples of vascular plants. Give some examples of non-vascular.

Vascular – ferns, trees, horsetails,

Non Vascular – moss, liverworts

15. List some characteristics of plants.

Have cell walls, have roots, range in height

16. What are some adaptations that help plants live on land?

Cell walls, a cuticle, more complex methods of reproduction

17. Describe how the coal used today was formed.

Ancient seedless plants died and compacted,turning into peat. Compression over a long time changed peat into coal.

18. List the major functions of a plant’s roots.

Anchor the plant, absorb water and soil nutrients, store food

19. List the major functions a of plant’s stem.

Stores food and water, structural support for the plant, moves material between the leaves and the roots

20. What is the major function of a plant’s leaves?

To make food through photosynthesis

21. Define: invertebrates, vertebrates, herbivores, carnivores, omnivores, detritivores

invertebrates – animals without a backbone

vertebrates – animals with a backbone

herbivores – animals that eat only plants

carnivores – animals that eat only animals

omnivores – animals that eat both plants and animals

detritivores – animals that feed on small bits of decaying organisms

22. What are some characteristics that all animals share?

Made of many cells, digest their food, have cells with a nucleus and organelles

23. About 97% of all animal species are (invertebrates or vertebrates).

invertebrates

24. Define: community, population, habitat, niche, and ecosystem

Community – all the populations in an ecosystem

Population – organisms in an ecosystem that belongs to one species

Habitat – the place in which an organism lives

Niche – how an organism survives in its environment

Ecosystem – all the organisms living in an area and the nonliving features of their environment

25. Define: food chain, producers, consumers, biosphere, and ecology

Food chain –the feeding relationships among the organisms in an ecosystem

Producers – organisms that use an outside energy source to make energy-rich molecules

Consumers – organisms that cannot make their own energy-rich particles

Biosphere – the part of Earth that supports life

Ecology – the study of interactions among organisms and their environment

26. Define: symbiosis, mutualism, commensalism, parasitism

Symbiosis – a close relationship between species

Mutualism – a symbiotic relationship in which both species benefit

Commensalism – a symbiotic relationship in which one partner benefits but the other is not affected

Parasitism – a symbiotic relationship in which one organism benefits but the other is harmed

27. The ____ biomes are found at the same latitudes as deciduous forests, but receive less precipitation.

Grassland

28. Give some examples of freshwater ecosystems.

Rivers, Lakes, ponds, swamps

29. Describe each of the following of rainforest zones: forest floor, understory, canopy, and emergents.

Forest floor – ground level; many insects and the largest mammals in the rain forest live here

Understory – dark, cool environment under the canopy of leaves but above the ground; insects, reptiles, and amphibians live here

Canopy – includes the upper parts of trees; insects, birds, reptiles, and mammals live here

Emergents –giant trees that are much higher than the average canopy tree; birds and insects are found here

Match each biome with the correct description. Each biome may be used more than once.

Desert

Tropical Rain Forest

Taiga

Grassland

Temperate Deciduous Forest

Tundra

Temperate Rain Forest

______30. consists of forest floor, understory, canopy, and emergents tropical rain forest

______31. dominate plants lose their leaves every autumn temperate deciduous forest

______32. populated by caribou, reindeer, snowy owls, and geese tundra

______33. has greatest variety of organisms on Earth tropical rain forest

______34. dominate plants are cone-bearing evergreen trees taiga

______35. dominate plants are grasses grassland

______36. cold, dry, tressless biomes in far north tundra

______37. populated by cacti and kangaroo rats desert

______38. usually have four distinct seasons temperate deciduous forest

______39. populated by moose, bears, lynx, shrews, and foxes taiga

______40. perfect for growing crops and raising cattle and sheep grassland

______41. dominate plants are firs, spruces, and cedars that grow very high temperate rain forest