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35 questions
A sequence of three bases in a messenger-RNA molecule is known as a
codon
nucleotide
polypeptide
gene
If a portion of a messenger RNA (mRNA) molecule contains the base sequence A-A-U, the corresponding transfer RNA (tRNA) base sequence is
A-A-U
T-T-A
G-G-T
U-U-A
The process shown in the diagram is known as
photosynthesis
DNA replication
protein deconstruction
protein synthesis
What do the letters A, G, C, and T represent in DNA nucleotides?
phosphate groups
deoxyribose sugars
nitrogenous bases
ribose sugars
In a portion of a gene, the nitrogenous base sequence is T-C-G-A-A-T. Which nitrogenous base sequence would normally be found bonded to this section of the gene?
U-G-C-U-U-A
A-C-G-U-U-A
A-G-C-T-T-A
U-G-C-A-A-U
A strand of DNA in a skin cell contains the bases:
A-T-G-C-C-A-T-C-G-G-T-A
After the cell is exposed to ultraviolet light, the strand contains the bases:
A-T-G-G-C-C-A-T-C-G-G-T-A
Which statement describes the result of this exposure?
A new base has been inserted (added).
A base has been deleted.
One base has been substituted for another.
There have been no changes in the bases.
The order of the DNA bases in a gene determines the order of the amino acids that are strung together in a chain at the ribosome. When the chain is complete and folded in a certain way, it makes a ...
carbohydrate
carbohydrate or protein depending on the gene instructions
protein
lipid or a carbohydrate depending on the gene instructions
Selective breeding occurs when ___________ decide(s) which organisms should be bred together.
nature
humans
the most powerful organism (such as when the most powerful wolf prevents other males from mating)
female organisms (such as when female birds select their mate based on his bright colors)
Sickle cell trait occurs when a person has one normal gene for hemoglobin (S) and one abnormal gene (s). From the choices select the one that is FALSE about sickle cell TRAIT:
A person with sickle cell trait gets tired more easily because their red blood cells can't carry as much oxygen as they would if all the red blood cell were normal.
can be an advantage if a person lives in an area where the disease called malaria is present
has no advantage if a person lives in an area where the disease called malaria is not present.
causes greater health problems than sickle cell anemia.
To be passed to the next generation a mutation must be present in
skin cells
sex cells (gametes, aka sperm and eggs)
the zygote
somatic cells
Who is given credit for developing the theory of evolution?
Charles Darwin
Christopher Darwood
Charles Darwood
Christopher Darwin
Natural selection produces changes most quickly in
species with short reproductive cycles
individual pathogens killed by antibiotics
complex multicellular organisms
individuals that produce a small number of offspring
Which factor would be LEAST likely to contribute to the development of a new species?
plentiful resources within the environment occupied by the species
increased genetic variation within the species
changes in the environment of the species
the ability of the species to increase its numbers by sexual reproduction
What is the term that describes traits that increase an individual's chance to survive and reproduce?
Maladaptations
Adoptions
Variations
Adaptations
Do individual organisms adapt to an environment because they need to survive?
Yes. If they don't adapt they will die.
No. Individuals can't adapt. They either are born with adaptations or they aren't.
Yes. They adapt by random mutations during their lifetime.
Yes. The environment can force an individual organism to mutate during its lifetime.
What is a keystone species?
A species that helps to hold an ecosystem together
A species that lives in or around rocks
Keys and stones have nothing to do with ecology
A species found only in Pennsylvania, which is nicknamed "The Keystone State."
What is a trophic cascade in an ecological system?
a process triggered by the removal or addition of a top predator that causes changes throughout the food pyramid.
a process triggered by the removal or addition of a top predator that causes no changes throughout the food chain.
a process triggered by the removal or addition of certain producers that causes no changes throughout the food chain.
a process triggered by the removal or addition of a primary consumer that causes changes throughout the food pyramid.
Which two of the following is (are) abiotic factors that are parts of ecosystems?
rabbit
temperature
wind
grass
According to the graph, what is causing the deer population to decrease?
They got sick
The wolf population is decreasing
The wolf population increased
They ran out of food
The exact same trait can be an advantage OR a disadvantage - it all depends on the environment that the organism is in.
Yes - that's true. The traits that deer in New York State have are good for survival in New York, but would be a disadvantage if the deer were transferred to Florida swampland.
No - that's false. Humans have pretty much the same traits as a species and we can live in any environment.
You are studying a population of rock pocket mice with dark-colored fur that lives on volcanic rock. You take a DNA sample from a member of this population and find the DNA sequence of a gene known to play a role in fur color. The gene sequence you identified is exactly the same as the gene in another rock pocket mouse population with dark-colored fur that lives on a different patch of volcanic rock far away. Which of the following could explain this observation?
The mice in the two populations evolved from a common ancestor..
The volcanic rock caused the same mutation in each rock pocket mouse population, resulting in dark fur.
The exact same random mutation happened by chance in the two different populations
For the rock pocket mouse, which of the following contribute to selective pressure from the environment that favor dark-colored fur? (Choose all that apply)
Predators
Genetic mutations
Rock color
The phenomenon that refers to a higher occurrence of dark body colors in animal species that live in habitats darkened by soot or other pollutants caused by humans is known as
industrial revolution
industrial melanism
pollution selection
Kettlewellanism
All the possible gene combinations in a population.
allele
gene pool
genome
mitosis
Evolution can occur at different rates; however, for evolution to occur, there must be
genetic variations within a species
extinction of the species
asexual reproduction
no change in the genes of an organism
In natural conditions where natural selection is at work, the life of organisms is all about...
adapting.
surviving.
moving to a new ecosystem.
In the human-influenced world where artificial selection is at work, the life of organisms is all about...
surviving.
producing traits desired by humans.
playing the role of nature.
In which biome is New York located?
tropical rainforest
temperate rainforest
temperate deciduous forest
alpine forest
In an mRNA vaccine, mRNA from the virus that causes Covid-19 goes to a ribosome in human cells, where it it is translated by the tRNA. The tRNA brings the right amino acids in the right order and a part of the virus protein is synthesized.
True
False
Which one is correct?
Antigens are the foreign molecules that don't belong in your body, and antibodies are the molecules that your body makes to fight the antigens.
Antibodies are the foreign molecules that don't belong in your body and antigens are the molecules that your body makes to fight the antibodies.
The six points of Darwin's Theory of Evolution are
Variation
Adaption
Compensation
Nature
Overpresentation
Similarities
Variation
Adaptation
Competition
Natural Selection
Overproduction
Speciation
Variation
Mutations
Environmental Pressure
Adaptation
Sexual Reproduction
Recombination
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