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Review for Populations and Ecosystems:
Inv. 1: Milkweed Bugs
1.
What are 2 ways you can tell the difference between a male and female milkweed bug?
1. Size – Female is larger than the male.
2. There is a different pattern on belly.
2.
A proboscis distinguishes a true bug from other insects.
3.
What are the main characteristics of all insects?
Have 3 body parts, 6 legs, reproduce with male
and female
4.
What is molting and why do insects molt?
Molting is when an insect sheds its exoskeleton in
order to grow.
Inv. 2: Sorting Out Life
1.
What is a population? Give an example of a population.
A population is more than one individual. A
population example is milkweed bugs.
2.
Trees, moss, and birds are an example of a
community.
3.
What is the difference between Abiotic and Biotic?

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Abiotic means non- living like rocks, sand, temperature, water. (never living)
Biotic means living like animals, plants (or things
that are dead).
4.
Abiotic factors + Biotic factors = An Ecosystem
5. Jane Goodall studied which animals? Chimpanzees
Inv. 3: Miniecosystems
1.
What type of environment does a terrestrial organism live in?
A land environment
2.
What type of environment does an aquatic organism live in?
A water environment
3.
List the planetary spheres from the Biosphere II article:
Hydrosphere, Lithosphere, Biosphere, Atmosphere
4.
Where is phytoplankton found? (It is a single-celled algae)
OCEANS
5.
In a food web the arrow points to the animal that eats the other
animal. We say this the direction of ENERGY flow.

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Inv. 4: Mono Lake
1.
What is a carnivore? Is an alligator an example of one?
A carnivore is an organism that eats other
animals. Yes, an alligator is a carnivore.
2.
What is another name for a plant in the food chain?
Producer
3.
What is a food chain? A sequence of organisms
that eat one another in an ecosystem.
4.
If a producer dies (algae), what would happen to the primary consumers in an ecosystem?
The primary consumers would also die because
they depend of the producers.
5.
If the number of producers were reduced, what would happen to the primary consumers, secondary consumers, third-level consumers?
Each level would be affected and the numbers at
each level would be reduced.
6.
What would happen to a body of water (pond) over
2,000 years?
The pond would become a field.
Inv. 5: Finding the Energy

1.
The important product of photosynthesis is
OXYGEN.
2.
What is a heterotroph and how does photosynthesis help it?
A heterotroph is an organism that cannot make its own food and must eat other organisms –
plants or animals.
3.
What process allows plants to get the energy they need?
PHOTOSYNTHESIS
4.
Plants use the energy from the SUN to make food.
5.
How does an animal get energy? An animal gets
energy by eating plants and animals.
6.
How is a heterotroph different from an autotroph?
A heterotroph cannot produce its own food. An
autotroph produces its own food.
7.
What 3 things are needed for photosynthesis?
SUNLIGHT, CARBON DIOXIDE AND WATER
Inv. 6: Population Size
1.
List 4 examples of limiting factors for a population.
Examples include:
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5 weather, disease, starvation, space (limited), old
age
Inv. 8: Adaptations
1.
What does an adaptation allow an organism to do?
An adaptation allows an organism to survive and
reproduce.
Inv. 9: Genetic Variation
1.
Explain the difference between a recessive trait and a dominant trait.
A dominant trait is a stronger trait. – Will always
“trump” a recessive trait
A recessive trait is a weaker trait. – Must have a combination of TWO recessive traits to get the
outcome of a recessive trait.
2.
Phenotype refers to the physical characteristics of
an organism.
3.
Genotype refers the combination of paired alleles.
4.
What makes up a gene?
Two alleles on a pair of chromosomes make up a
gene.
5.
What is a heterozygous gene and is it always recessive?

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A gene composed of two different alleles (a dominant and recessive). No, it is never recessive. The dominant allele will over power the recessive allele. Dd would show the dominant
trait.
6.
Which is a stronger trait? Dominant or Recessive
(circle one)
7.
What is heredity?
The passing of traits from one generation to the
next.
8.
Which scientist (biologist) is associated with genetics research?
Gregor Mendel
9.
How can you explain people having different traits and features?
(like red hair, blonde hair, brown hair)
Different genes are expressed in an organism
which give it characteristic traits.
10.
What structure contains genes?
Chromosomes contain genes.
11.
How is genetic information supplied by each parent?

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The alleles from each parent carries ½ of the
offspring’s genetic information in
12.
Draw an example of a Punnett Square. What would the parent Punnett Square look like and then the F1 offspring?
Male: Aa
Female: aa
A a
a a
13.
Being good at sports could be an INHERITED trait. (If you got it from your parents.)
Inv. 10: Natural Selection
1.
What is natural selection? How can it affect the population?
The process by which the individuals best adapted to their environment tend to survive and pass
their traits to the next generations.
2.
What is an example of a variation? Think finches from Galapagos Islands.
The finches developed a variation in beak
structure to obtain food.

3. How has selective breeding been used?
To create different breeds of dogs and vary the
change and taste of apples.
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