7th
grade Science Mock CRCT Test
1.
Competition occurs when two or more organisms within an ecosystem seek the
same resource. Which of the following are examples of resources that organisms
may compete for?
I. habitat
II. water
III. sunlight
IV. food
A. I, II, III, and IV
B. IV only
C. II and IV only
D. I, II, and IV only
2.
A mite is a tiny organism that may "ride" on top of an insect such as a beetle in
order to move quickly from place to place.
This relationship between the mite and the beetle would be an example of
commensalism if...
A. The beetle is neither harmed nor helped by the mite.
B. The beetle is unable to catch prey because it is slowed down by the mite.
C. The mite protects the beetle from predators.
D. The beetle eats the mite.
3.
Examine the drawing of the environment below:
Which of the following organisms could most likely live in this type of
environment?
A. toucan
B. scorpion
C. beaver
D. grizzly bear
4.
All ecosystems contain at least one population of organisms. Which of the
following could be considered a population?
A. a grove of apple trees
B. a pile of clamshells
C. a group of deer and mice
D. a mockingbird and its nest
5.
Which of the following is a primary consumer in the food web shown above?
A. algae
B. grasshopper
C. earthworm
D. bacteria
6.
Which relationship below is an example of competition in an ecosystem?
A. Squirrels nest in an oak tree and insects live under the ground near the tree.
B. Rabbits eat the grasses and shrubs in a meadow and wolves eat the rabbits.
C. Bald eagles and black bears fish from the same mountain lake.
D. Birds eat insects that cattle disturb in their grazing and occasionally ride on the
cows' backs
7.
The following diagram represents how energy flows through ecosystems:
sunlight
plants
herbivores
carnivores
What would most likely occur in an ecosystem if a nearby volcano erupted and
filled the sky with dust particles, which caused significantly less sunlight to reach
the ecosystem over the course of a year?
A. Many plants would die, but the animals would survive.
B. The plants would begin using nutrients in the soil for energy.
C. Many plants and animals would die off.
D. The lack of sunlight would not significantly impact the ecosystem
8.
The trees in a tropical rainforest are often over 100 feet tall. Together, the upper
portions of the trees form a canopy of leaves and branches that block sunlight
from reaching the ground.
The strangler fig has adapted a method of depositing its seeds on the branches
of other trees. When one of these seeds sprouts, its stem and branches grow
upward, eventually forming a new canopy that blocks sunlight from the host
tree. The roots of the strangler fig wrap around the host tree and may eventually
strangle the host tree.
This example demonstrates ______ and ______.
A. competition, parasitism
B. predation, competition
C. parasitism, predation
D. cooperation, mutualism
9.
Look at the diagram above of a food web. What would happen to the food chain
if a drought occurred, and the vegetation did not grow?
A. The fox would only be able to live off of energy from the sun.
B. The fox would not survive.
C. The caterpillar, partridge, and rabbit would not survive.
D. All of the animals in this web would starve.
10.
Which of the following statements is true?
A. A producer must be a plant.
B. A producer usually obtains food by hunting other organisms.
C. Consumers depend upon producers for food.
D. A human that prepares his/her own meals is a producer.
11.
A bird builds its nest on the branch of a tree. This relationship between the bird
and the tree is an example of ________.
A. mutualism
B. parasitism
C. competition
D. commensalism
12
Which relationship below is an example of a predator-prey relationship?
A. a rabbit eats grasses
B. a pet fish eats fish food
C. a giraffe eats the leaves from tall trees
D. a coyote eats a hen
13.
If a new organism is found that has a white coat in winter and a light brown coat
in summer, in which biome is it most likely to belong?
A. tropical rainforest
B. coniferous forest
C. tundra
D. desert
14.
Which of the following features would help a plant adapt to a tropical forest
biome?
A. deep, branching roots
B. waxy leaves with drip tips
C. thick, rough bark
D. wide leaves with fine
15.
Which of the following biomes is most likely to have cold, windy weather and a
relatively low amount of available oxygen?
A. coniferous forest
B. mountain
C. grassland
D. desert
16.
An estuary
A. filters dirt and pollution out of the water.
B. is only found inland.
C. is a small watershed.
D. is a deposit formed where a fast flowing stream flattens
17.
A biome that experiences the seasons of winter, spring, summer, and fall, and
non-extreme temperatures is likely to be a(n) _______ biome.
A. tropical
B. tundra
C. arctic
D. temperate
18.
Which biome is found near the polar ice caps?
A. taiga
B. tropical rainforest
C. coniferous forest
D. tundra
19.
Which of the following bodies of water are included in the freshwater biome?
I. rivers
II. oceans
III. lakes
IV. streams
A. I, II, III, and IV
B. II only
C. I, III, and IV only
D. II and III only
20.
Which of the following is true about the marine biome?
A. Organisms with a low tolerance for salt thrive in the marine biome.
B. The marine biome experiences a smaller degree of temperature change than
the terrestrial biome.
C. The marine biome includes the freshwater and saltwater biomes.
D. The terrestrial biome has a major effect on the weather patterns of the marine
biome.
21.
A particular species of lizard lives underground for much of the day, escaping the
heat. This species of lizard probably lives in a _____.
A. ocean
B. tundra
C. desert
D. deciduous forest
22.
Where is the tropical rainforest biome found?
A. in northern coniferous forests
B. in mild temperature climates
C. near the polar ice caps
D. near the equator
23.
If a new organism is found that has a white coat in winter and a light brown coat
in summer, in which biome is it most likely to belong?
A. tundra
B. coniferous forest
C. tropical rainforest
D. desert
24.
Spider monkeys live in a biome with many trees. They move around by swinging
from tree to tree. Spider monkeys do not build a nest or take shelter in a cave.
Instead, they sleep high up in a tree on a wide branch. Spider monkeys mostly
eat fruits and nuts. What type of biome do spider monkeys most likely live in?
A. coniferous forest
B. temperature deciduous forest
C. tropical rain forest
D. savanna
25.
The _______ biome is the largest on Earth.
A. terrestrial
B. freshwater
C. polar
D. marine
26.
In pea plants, the allele for tallness (T) is dominant to the allele for shortness (t).
In the cross between a tall pea plant and a short pea plant shown below, what is
the probability that the resulting offspring will be tall?
T t
t
? ?
t
? ?
A. 75%
B. 100%
C. 25%
D. 50
27.
Select the choice below that best shows various types of genetic material in
order from simplest to most complex.
A. chromosome
B. genome
C. genome
D. gene
genome
gene
chromosome
gene
gene
chromosome
chromosome
genome
28
The instructions, or code, that is responsible for all the inherited traits of an
organism...
A. is formed after an organism is fully-grown.
B. is stored within the mitochondria of cells.
C. is held in genetic material called DNA.
D. is passed from the offspring to the parent.
29.
Many human diseases follow the dominant/recessive pattern of inheritance. If an
individual possesses an allele for a disease, but does not have the disease, this
person is known as a ___________.
A. carrier
B. mutant
C. genotype
D. messenger
30.
In humans, the allele for attached ear lobes (e) is recessive to the allele for free
ear lobes (E).
If both of Lisa's parents have attached ear lobes, then...
A. Lisa may have either attached ear lobes or free ear lobes.
B. Lisa must have her ears pierced.
C. Lisa must have free ear lobes.
D. Lisa must have attached ear lobes.
31.
_________ can be described as alternate forms of a particular gene.
A. Chromosomes
B. DNA molecules
C. Chromatids
D. Alleles
32.
Huntington's disease is a genetic disorder that can result in memory loss and
abnormal body movements. Huntington's disease results from a defective gene
(H) that is dominant to the allele that produces normal function (h). This means
that...
I. If someone is heterozygous for Huntington's disease, then
he/she will be a carrier but will not have the disease.
II. If a child has Huntington's disease, then at least one of his/her
parents has the disease.
III. If two parents do not have Huntington's disease, then their
children will not have the disease.
A. III only
B. II and III only
C. I and II only
D. II only
33.
Select the choice that best completes the following sentence:
A normal human body cell has a total of ___ chromosomes: ___ chromosomes
come from the mother and ___ chromosomes come from the father.
A. 92, 46, 46
B. 23, 11, 12
C. 46, 23, 23
D. 23, 12, 11
34.
B b
B ? ?
b ? ?
Which of the following correctly completes the Punnett Square above?
A. BB Bb
Bb bb
B. bb Bb
Bb BB
C. BB bb
Bb Bb
D. Bb Bb
BB bb
35.
In fruit flies, the allele for white eyes (W) is dominant to the allele for red eyes
(w). Two heterozygous fruit flies are crossed, resulting in many offspring.
Which of the following would best describe the population of offspring?
A. All of the offspring population is white-eyed.
B. The majority of the offspring population is red-eyed.
C. The majority of the offspring population is white-eyed.
D. About half of the offspring population is red-eyed, and the other half of the
population is white-eyed.
36.
In humans, the ability to roll one's tongue follows the dominant/recessive pattern
of inheritance. The allele for tongue-rolling is dominant to the allele for nontongue-rolling. If two homozygous parents can roll their tongues, what is the
probability that their child will also be able to?
Hint: Use the Punnett Square below to help you.
R R
R ? ?
R ? ?
A. 0%
B. 50%
C. 100%
D. 75%
37.
Sickle-cell anemia is a genetic disorder of the blood in which the shape of red
blood cells is distorted, resulting in a variety of health problems. The allele for
normal blood cell production (H) is dominant to the allele for sickle cell
production (h).
If one parent has sickle-cell anemia and the other parent is a carrier, what is the
probability that their child will have sickle-cell anemia?
Hint: Use the Punnett Square below to help you.
H h
h ?
?
h ?
?
A. 50%
B. 75%
C. 100%
D. 25%
38.
In a particular type of cat, coat color follows the dominant/recessive pattern of
inheritance. The allele for a brown coat (B) is dominant to the allele for a white
coat (b).
A cross between two white-coated cats would result in...
A. white-coated kittens or brown-coated kittens.
B. white-coated kittens only.
C. white-coated kittens with brown spots.
D. brown-coated kittens only.
39.
Which of the following is true about genes?
A. In humans, genes are passed to an offspring from two parents.
B. Genes are made up of smaller molecules known as chromosomes.
C. The genes of a particular organism can never change throughout its lifetime.
D. Genes are responsible for all the traits of an organism.
40.
Nutrients enter cells through the _____.
A. endoplasmic reticulum
B. plasma membrane
C. nucleus
D. ribosomes
41.
A ________ is a rigid layer that surrounds a plant cell, providing structural
support.
A. cell wall
B. nucleus
C. vacuole
D. lysosome
42.
In a cell, what is the function of the cell membrane?
A. It only maintains the cell shape.
B. It controls the entry and exit of substances.
C. It generates energy for the cell.
D. It removes waste and stores ingested food.
43.
Which of the following is a substance that is found between the cell membrane
and the nucleus, which primarily consists of water and holds organelles?
A. cell membrane
B. mitochondria
C. chloroplast
D. cytoplasm
44.
In which cell organelle does photosynthesis take place?
A. cell wall
B. mitochondrion
C. vacuole
D. chloroplasts
45.
Some unicellular organisms are similar to _____________ because they have
the ability to ____________.
A. plants, produce sound
B. birds, fly
C. animals, move
D. reptiles, lay eggs
46.
In a living organism, what is an organ?
A. the shell or skin of an organism
B. functional unit, or building block, of all organisms; smallest unit that can carry
on the activities of life
C. a group of similar cells that perform a common function
D. a structure composed of a number of tissues that work together to perform a
specific task
47.
What are the most basic building blocks of all organisms?
A. tissue
B. organs
C. blood
D. cells
48
What type of organism is a one-celled organism that functions as a single unit?
A. bicellular
B. multicellular
C. unicellular
D. precellular
49..
Once it has passed through the plasma membrane, this simple sugar is broken
down to make a form of energy needed by the cell. What is the name of the
simple sugar?
A. fat
B. water
C. glucose
D. protein
50.
In which cell organelle does photosynthesis take place?
A. chloroplasts
B. cell wall
C. vacuole
D. ribosomes
51.
Which cell organelle is where proteins are made?
A. mitochondrion
B. ribosomes
C. nucleus
D. vacuole
52.
Which of the following is an example of natural selection?
A. Cricket Frogs prefer to sleep during the day, while Red-eyed Tree Frogs prefer
to sleep during the night.
B. Rabbits with a mutation for longer, thicker fur survive an unusually cold
winter, while many normal rabbits do not survive.
C. Pesticides are sprayed in a field, resulting in an increase in crop growth and a
decrease in insect population.
D. To produce a more desirable fruit, a farmer crosses a tree that produces sweet
oranges with a tree that produces large oranges.
53.
Which of the following is true about natural selection?
A. Natural selection usually causes a species to change suddenly.
B. Natural selection usually causes a species to change gradually.
C. Natural selection is the only cause of changes in a species.
D. Natural selection does not cause a species to change.
54.
Why is the fossil record unable to provide a full portrait of the times in which the
fossilized animals and plants lived?
A. The fossil record does not include nests.
B. The fossil record does not include plants.
C. The fossil record is made of stone.
D. The fossil record is incomplete
55.
Consider the following situation:
A species of birds lives in a particular niche. As their population increases, many
of these birds migrate to new niches with different food sources.
In niches where hard seeds and nuts are the main food sources, the birds with
stronger beaks succeed and grow in population. In niches where small insects
and larvae are the main food sources, the birds with longer, narrow beaks
succeed and grow in population.
This is an example of how
A. genetic engineering leads to more diversity.
B. natural selection leads to more diversity.
C. genetic engineering leads to less diversity.
D. natural selection leads to less diversity.
56.
Fossils are most commonly found in which type of rock?
A. Paleolithic
B. metamorphic
C. igneous
D. sedimentary
57.
The main purpose of the endocrine system is to produce:
A. hormones.
B. neurons.
C. hemoglobin.
D. white blood cells
58
The purpose of the digestive system is to break down food into simple molecules
that the _______ of the body can use.
A. chemicals
B. microorganisms
C. enzymes
D. cells
59
The skeletal part of the musculoskeletal system:
A. protects the organs of the body.
B. eliminates wastes from the body.
C. helps the body to create heat.
D. produces facial expressions
60.
The major function of the respiratory system is to:
A. maintain the digestive system of the body so that it can continue to operate.
B. cleanse the body of toxins, poisons, and harmful chemicals.
C. give the heart the energy it needs to circulate blood.
D. provide oxygen to the body and eliminate carbon dioxide from the body.