Q2 Exam Envi. Sci. SG

Give three examples of abiotic factors that impact ecosystems

temperature, light, and water

organism

an individual animal, plant, or single celled life form

population

a group of individuals of the same species living within a given area

community

a group of interacting species living in the same location

ecosystem

a geographic area where plants, animals, and other organisms work together to form a livable area

biome

an area that is classified by the species that live in that location

biosphere

made up of the parts of Earth where life exists

explain how natural selection causes animals to evolve

less favorable-traited wildlife is killed off, which leads to the more favorable-traited wildlife to reproduce, and pass on their better traits

food chain group names

1. Producers 2. Primary Consumers 3. Secondary Consumers 4. Tertiary Consumers

give an example of a food chain from producer to tertiary consumer with real animals

flowers (producer) → bees (primary) → frogs (secondary) → snakes (tertiary)

____ is an anatomical, physiological, or behavioral change that improves a population’s ability to survive

adaptation

describe how a chemical like mercury or DDT gets biomagnified in a food chain

by consuming other animals ; predators eat other organisms and absorb the contaminants that their food sourced contained

artificial selection

the identification by humans of desirable traits in plants and animals, and the steps taken to enhance and perpetuate those traits in future generations

explain how selective breeding was being studied with foxes

the breeders were specifically breeding calm foxes, with other calm foxes and meaner foxes, with other mean foxes. this resulted in the babies having the same characteristics as their parents

explain how we genetically engineered corn to be pest resistant in the gizmo

by taking the best traits and adding in a pesticide

name the 6 kingdoms of organisms

a. archaebacteria b. eubacteria c. protist d. fungi e. plantae f. animalia

compare invertebrate and vertebrates

invertebrates = without a spine

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worm digestive tract

mouth → pharynx → esophagus → crop → gizzard → intestine → anus

explain three ways the nitrogen-fixing can occur (getting N2 out of the atmosphere and into a usable form)

a. assimilation (fertilizer → live plants

b. ammonification (animal → animal waste)

c. denitrification (ocean → atmosphere)

where can most nitrogen fixing bacteria be found

root nodules of legumes (beans, peas, clover)

explain the role of decomposers in both the nitrogen and phosphorus cycle

breaks down substances (dead plants/animals)

describe what happens when runoff with fertilizer (N and P in it) enters an aquatic ecosystem

causes rapid growth of algae, algal blooms

algae depletes nutrients that are important for aquatic life

describe the difference between a primary and secondary succession

Primary: ecological succession that begins in an area where no biotic community previously existed

Secondary: following a disturbance that destroys a community without destroying the soil

what is a pioneer species

first species to populate an area during a succession

what is an example of a pioneer species

bacteria, lichen, mosses, fungi