Ecology Review June 2009 Answers

Science 10 - Ecosystems Ecology Review

Amphibians are exposed to more environmental hazards than other forms of life because: they spend part of their life in an aquatic environment and part in a terrestrial environment.

Frogs are particularly good indicators of ecological damage to the environment because: • All of the above. In other words … (a) pollutants can enter their bodies directly through their skins. (b) they are susceptible to ultraviolet radiation. (c) their ability to reproduce is affected by acid rain.

Which one of the following statements is true? (b) Tadpoles are herbivores and mature frogs are carnivores. Why? Tadpoles consume aquatic plants and algae, while mature frog eat insects.

The term “consumer” is used to define an organism that: (c) may eat plants or animals;

Populations of native species in the Great Lakes have suffered from the introduction of exotic species that cause difficulties most often because they: (c) interfere with the food chain by competing for sources of food;

Biodiversity is, a term that is used to describe, the differences that exist in the:

(b) variety of organisms

A group of organisms of the same species living together is referred to as a(n):

(c) population

A group of organisms of different species that live and interact together is referred to as a(n):

(b) community

An organism that makes its own food from basic nutrients is called a(n):

(a) autotroph

An organism that consumes other living things is called a(n):

(b) heterotroph

An example of an autotroph is a:

(c) maple tree

An example of a heterotroph is a:

(b) deer

For the food chain shown below, construct a simple table in which you identify the stage of the food chain that each organism occupies.

Algae …… Producer Crustacean ….. Primary Consumer Fish ….. Secordary Consumer Bald eagle ….. Top carnivore

Populations of native species in the Great Lakes have suffered from the introduction of exotic species that cause difficulties most often because they:

(c) interfere with the food chain by competing for sources of food

Biodiversity is a term that is used to describe differences that exist in the:

(b) variety of organisms

The role that an organism plays in the ecosystem is called a:

(c) niche

A non-native species that is introduced into an ecosystem is said to be:

(b) exotic

After DDT had been used for a period of time: (b) it began to accumulate in the bodies of top carnivores.

Modern water-soluble pesticides have less effect on top predators because: (d) they do not accumulate in the bodies of the top predators.

Which of the following is not considered to be a reservoir for inorganic carbon?

(a) trees

A sustainable ecosystem is one that: • meets the needs of present generations without compromising the needs of future generations

The biome with the greatest biodiversity in Canada is the:

•temperate deciduous forest

The most fragile biome in Canada is the:

•tundra

The biome that covers the greatest amount of area in Canada is the:

•boreal forest

The biome with the least amount of naturally-occurring ecosystems remaining in Canada is the:

•grasslands

Complete the following chemical equation to show the number of molecules of reactants and products required for the reaction to occur. 6 CO

2

+

6H O 2

+ light energy

C6H12O6

+

6O

2

Frogs occupy different positions on the food chain depending on whether they are in the tadpole or mature stage.

Construct a food chain of at least four steps for: Algae Cattails

tadpole

water boatman

grasshopper

mature frog

perch heron

Define:

Extinct: a species that has disappeared everywhere Threatened: a species that is likely to become endangered if factors affecting it are not reversed Extirpated: a species that no longer exists in part of Canada but can be found elsewhere Endangered: wildlife species facing imminent extirpation or extinction Special concern: A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats

Students on a field trip are asked to describe some of the communities they observe. Make a list of at least four biotic factors and four abiotic factors they would probably experience in examining a pond.

Biotic: water lilies, cattails, frogs, dragonflies, minnows, etc. Abiotic: water, rocks, clay, wind, sunlight, etc.

How many trophic levels are represented in the longest food chain in this food web? Six (6) Name the species in that chain in order from the first trophic level. Aquatic plants, tadpoles, dragonflies nymphs, frogs, raccoons, hawk

If butterflies were removed from this ecosystem what organisms would be affected and how would this affect them? • Frog/Dragonflies feed on them, their populations would likely decline. • Hawk & raccoons populations would be reduced as they have less food.

Wild Rose -> aphid -> ladybug ->insect-eating bird

Ecological pyramid Pyramid of numbers

Pyramid of biomass

Pyramid of energy

Canadian Biomes – abiotic factors •

Grassland

•

Temperate deciduous forest

•

Tundra

•

Boreal forest

• rich fertile soil with 25 to 75 cm of precipitation per year • higher temperatures with up to 100 cm of precipitation per year • permafrost and very low precipitation each year • acidic soil containing some water and 40 cm of precipitation or more per year

Canadian Biomes – biotic factors •

Temperate deciduous forest

•

Tundra

•

Grassland

•

Boreal forest

• Rich layer of undergrowth, as well as upper storey; deer, black bears, wolves and woodpeckers. • rapid-flowering plants, mosses, and lichens; caribou, ptarmagin, and lemmings • fescue grasses with trees only along rivers; grasshoppers, bison, wolves, and hawks • evergreen trees; squirrels, deer, pine martens, and seed-eating birds