LET
REVIEWER: GENED : SCIENCE
1. In Chemistry, the Periodic Table of the elements
is an organized array of all the chemical elements in order of _______.
A. increasing number of protons in the atomic
nucleus
B. date of discovery
C. decreasing atomic number
D. increasing
number of neutrons in the atomic nucleus
2. It is the
most abundant gas in the atmosphere?
A. Oxygen
B. Nitrogen
C. Helium
D. Argon
3. The earth’s crust is composed mainly of this
element.
A. Silicon
B. Aluminum
C. Oxygen
D. Iron
4. A scientist studied a species of fish. She found
that when a certain nutrient was added to the diet of the fish just after
hatching, the fish gained an average of 3
kilograms in the first year. What additional
information is needed to determine whether the nutrient is affecting the growth
of the fish?
A. how much adult fish gained on average when the
same nutrient was added to their diet
B. how much of the nutrient is available for the
fish species in their natural surroundings
C. how much other species of fish gain in the first
year when the nutrient is added to their diet
D. how much newly hatched fish in this species gain
in the first year without the nutrient in their diet
5. A scientist studied the number of eggs a species
of bird lays each year. He found that the most common number of eggs laid in a
year is three. Which statistical measurement did the scientist find?
A. the mode of the number of eggs laid in a year
B. the mean number of eggs laid in a year
C. the median number of eggs laid in a year
D. the range of the number of eggs laid in a year
6. Louis Pasteur discovered that the bacteria in a substance can be
killed by heating the substance for a short period of time. Which of these
practices benefited most from Pasteur’s discovery?
A. building ovens and other heating devices
B. storing foods for longer periods of time
C. creating medicines that cure infections
D. transporting living organisms without injuring them
7. In which situation would osmosis most likely
occur in cells?
A. across a permeable membrane that separates
solutions of the same concentration
B. across a non-permeable membrane that separates
solutions of the same concentration
C. across a permeable membrane that separates
solutions of different concentrations
D. across a non-permeable membrane that separates
solutions of different concentrations
8. Which statement best describes the process of
respiration?
A. Water and sugar are used to in the process that
provides energy to cells; oxygen and carbon dioxide are its waste products.
B. Oxygen and carbon dioxide are used in the
process that provides energy to cells; sugar and water are its waste products.
C. Carbon dioxide and sugar are used in the process
that provides energy to cells; water and oxygen are its waste products.
D. Oxygen and sugar are used in the process that
provides energy to cells; water and carbon dioxide are its waste products.
9. What is a difference between mitosis and
meiosis?
A. In mitosis, the products are identical to the
parent cell, while in meiosis the products are different from the parent
cell.
B. Mitosis occurs in all the cells in animals and plants,
while meiosis occurs only in bacteria.
C. In mitosis, one cell divides into two cells,
while in meiosis two cells combine to make one cell.
D. Mitosis involves separating the chromosomes,
while meiosis involves only the cytoplasm of the cell.
10. In humans, B is the allele
for brown eyes and b is the allele for blue eyes. Two brothers both have brown
eyes, but one of them has both the B and b alleles while the other only has B
alleles. Which statement is true about the brothers?
A. They have the same genotype and phenotype.
B. They have the same phenotype but different genotypes.
C. They have different phenotypes and genotypes.
D. They have the same genotype but different phenotypes.
11. Use this Punnett square to
answer the question.
In horses, the gene for white
hair (W) is dominant to the gene for non‐white hair (ω). A horse with
genotype (WW) was crossed with a horse with genotype (ωω), as shown in the
Punnett square.
What fraction of the offspring
should be expected to have white hair?
A. none
B. one‐half
C. three‐quarters
D. all
12. What do scientists mean when they refer to a population?
A. all the organisms in an ecosystem
B. all the species that share similar anatomical features
C. all the animals that acquire resources through similar methods
D. all the interbreeding members of a certain species in an
ecosystem***
13. Which relationship is mutualistic?
A. an insect that lives and feeds on the body of an alligator
B. an ant that lives on a plant and defends the plant from other
insects
C. a bird that migrates to follow the movements of the butterflies that
it eats
D. a deer that eats one kind of plant, which allows another kind of
plant to grow in its place
14. Which example describes a
behavioral adaptation?
A. A bird builds its nest in the ash near a volcano.
B. A whale has the ability to hold its breath for 20 minutes.
C. A fox’s hair is white in the winter and brown in the summer.
D. A monkey has long arms that allow it to swing from one branch to
another.
15. In a large forest with many
animals, there are only a small number of bears. Which of these most likely
limits the population of bears in the forest?
A. supply of food
B. type of tree
C. predation by carnivores
D. amount of suitable shelter
16. What is the main reason
humans need nitrogen to survive?
A. Nitrogen is used in respiration to generate energy.
B. Nitrogen is used in making the proteins in the body.
C. Nitrogen is used to help the body eliminate wastes.
D. Nitrogen is used by nerve cells to conduct impulses.
17. Which statement best
describes the roles of photosynthesis and respiration in the carbon cycle?
A. Respiration and photosynthesis both add carbon to the atmosphere.
B. Respiration and photosynthesis both remove carbon from the
atmosphere.
C. Respiration adds carbon to the atmosphere, while photosynthesis
removes carbon from the atmosphere.
D. Photosynthesis adds carbon to the atmosphere, while respiration
removes carbon from the atmosphere.
18. Scientists have observed an
increase in global temperatures over the past 100 years. Which phenomena do
scientists believe contributes to the increase in temperatures?
A. an increase in undersea volcanic activity
B. a decrease in the distance between Earth and the Sun
C. an increase in certain gases released during the use of fossil
fuels
D. a decrease in the amount of water on Earth due to overconsumption
19. Which flowchart shows a
likely path of a waste molecule through the body?
A. skin cell → blood → kidney → large intestine → rectum → out of body
B. muscle cell → blood → liver → blood → lung → out of body
C. bone cell → blood → liver → gallbladder → rectum → out of body
D. brain cell → blood → kidney → urine → bladder → out of body
20. A scientist plans to investigate the nervous system of sea slugs.
What should the scientist do first?
A. Develop a theory about sea slugs that can be tested.
B. Go to the ocean to observe the behavior of sea slugs.
C. Obtain several sea slugs and conduct experiments with them.
D. Review the research other scientists have done on sea slugs.
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Answers:
