NOW I KNOW THAT… Ecology and Selective Breeding CRCT Review
p.107 Food Webs • 1) A carnivore (frog) obtains matter (food) directly from a herbivore (grasshopper). • 2) A first-level consumer (herbivore) would consume plants (corn). • 3) A decomposer breaks now dead plants and animals which releases gases back into the atmosphere. • 4) Plants take in carbon dioxide through photosynthesis.
p. 113 Sunlight • 1) Plants use the sun’s energy to make sugars (their food) • 2) Ten percent of the energy in an energy pyramid is passed from each level (trophic levels). • 3) Sunlight is the ultimate source of energy for all living things because all food chains, webs, and energy pyramids begin with producers which get their energy from the sun. • 4) The first (bottom) level of an energy pyramid always has the most available energy.
p. 117 Environmental Conditions • 1) Any restrictions, including natural disasters, that limit resources for organism in an ecosystem is a limiting factor. • 2) If a population graph of animals peaks at one year then begins to decline, usually that means that an event has occurred that began to limit resources for those animals. • 3) If a graph line moves down from left to right then there is a decline. If the graph line moves up from left to right there is an increase.
p. 118,119 Check Your Progress • 1) Producers are usually the first organisms in a food chain, web, or energy pyramid. • 2) Scientist keep accurate records in order to validate their results. • 3) Even if your hypothesis is wrong, you still learn from the research.
pp. 118, 119 continued • 4) When an organism dies, the carbon in the body goes back into the air through decomposers. • 5) Producers = 1,000 kilocalories 100 kilocalories; simply move the decimal one place left for each level as it moves up. • 6) In a graph, carrying capacity will be shown as a horizontal line because it represents when the ecosystem has reached a balance.
p. 123 Relationships Between Organisms • 1) Competition occurs when two populations have limited resources. • 2) A parasite is like a predator. A host is like a prey because a parasite feeds from a host. • 3) Even organisms ( as small as bacteria) compete for food.
p. 129 Terrestrial Biomes • 1) Scientist use climate as a factor to classify a biome. • 2) A tundra is often called a dry desert because it, like a desert, receives 24cm or less of rainfall per year. • 3) Tropical rainforest are found at the same line of latitude as the equator, so as you move north you would encounter the savanna biomes. • 4) A tropical rainforest is characterized by boa constrictors, sloths, monkeys, vines, and ferns.
p. 135 Aquatic Communities • 1) Only about 3% of the earth’s water is fresh (drinkable) water. • 2) An estuary contains a mixture of salt and fresh water. • 3) Marine is a synonym for salt-water so an ocean or sea would be a good example of a marine ecosystem. • 4) The ocean is divided into zones according to depth. If sunlight can penetrate the surface then animal-like protists or aquatic plants can use photosynthesis.
p. 91 Selective Breeding • 1) Hybridization is a type of selective breeding where organisms with different traits are combined. • 2) Selective breeding is controlling traits which is done by people. • 3) A wolf is wild and dangerous, so if people wanted an animal like the wolf but more tame they would find the animals with the mildest temperaments to breed. • 4) If one species is bred only within its population then there will be few to no variations.