life science final

A scientist publishes a paper in a peer-reviewed journal; this paper is later retracted. Which of the following (if found to be true) is NOT a legitimate reason for the retraction?

Although the findings were not replicated by other researchers, some studies indicated that the original paper might suggest a valid line of reasoning and warrants further investigation.

Consider a gene with two alleles that shows complete dominance. When two heterozygotes for this gene breed, they have a 25 percent chance of producing a homozygous recessive offspring. The next time these two individuals breed, what are the chances they will once again have a homozygous recessive progeny?

25 percent

An mRNA molecule that is 99 bases long will create a protein composed of:

33 amino acids.

Sickle-cell disease is an inherited chronic blood disease caused by an autosomal recessive allele. Suppose a man with sickle-cell disease fathers a child by a woman who is a carrier for sickle-cell disease. What are the chances their children will exhibit the disease?

50 percent

Which of the following examples indicates a situation where the researcher is MOST likely to have a possible bias regarding his or her work?

A privately funded researcher is working on developing a genetically engineered and patented microbe to quickly digest oil spills. If successful, the microbe would be marketed worldwide.

When determining whether a claim about a new cleansing juice diet is scientific or pseudo science, which of the following is NOT a helpful question to ask yourself?

Are there a lot of people, including celebrities, endorsing the product as a healthy weight-loss method?

Which of the following would be a fact?

Bats with white noses have been observed in the wild.

A rapidly dividing cell is exposed to a chemical that converts the bond that forms between adenine and thymine to a stronger covalent bond. Which of the following is MOST likely to occur?

DNA replication would not occur because the two nucleotide strands that make up the DNA molecule would not be able to separate.

Which of the following is a part of accepted cell theory?

Every living organism is composed of one or more cells, and all living cells arise from preexisting cells.

A carwash attendant offers to treat Martin's windshield with a protective agent. This substance coats the glass, causing beads of water to easily roll off during a rain shower. Which of the following must be correct about the protective agent?

It must be hydrophobic.

The key enzyme used during transcription is:

RNA polymerase.

What are the stages of interphase?

S, G1, and G2

Scientific understanding can always be challenged, and even changed, with new ways of observing and with different interpretations. For example, new tools and techniques have resulted in new observations and the discovery of additional information. This has resulted in revised ways of understanding how molecules are moved across the plasma membrane of cells. Hence, there is no certainty in science, only degrees of probability (likelihood) and potential for change. In light of this understanding, which of the following statements is MOST meaningful?

Scientific knowledge is based on current knowledge.

Which of the following would be a theory?

Specific pathogens are directly responsible for specific diseases and conditions.

Which of the following is true of transcription?

The DNA molecule must unwind.

Why did Mendel analyze thousands of plants while conducting his research?

The likelihood of seeing a clear pattern is higher with a larger data set.

The polymerase chain reaction (PCR) technique could be developed only after the discovery of bacterial enzymes that were able to withstand high temperatures. Why was it necessary to use such enzymes?

The temperature required to separate DNA strands during PCR degrades other enzymes.

Which of the following is NOT a reason to scientifically evaluate the plausibility of claims made by a psychic who states that a missing child is alive and located in a particular area of the countryside months after the child went missing?

There is anecdotal evidence suggesting that psychics can predict the location of missing children.

Which of the following statements is true of chloroplasts?

They capture energy from sunlight.

Your own scientific literacy would NOT be helpful in answering which of the following questions?

Which movie should I watch this weekend?

The first human trial using CRISPR and approved by NIH used the system to edit:

a cancer patient's own immune system cells.

Which of the following genetic changes would NOT be passed from parent to child?

a mutation in a skin cell

Which term is best associated with a synapsed pair of homologous chromosomes?

a tetrad

A karyotype from an adult male indicates a chromosomal abnormality, which does not affect his health. Which of the following abnormalities is MOST likely seen?

a translocation between chromosome 14 and chromosome 15

An allele is:

a version of a gene.

Mismatch errors are:

almost always corrected by specialized proteins.

A chemical reaction that uses ATP to build cellular components is:

anabolic.

Cells that demonstrate anchorage independence:

are primed to become metastatic.

All of the following contribute to genetic uniqueness EXCEPT:

binary fission

The expression of most genes is regulated by:

both internal and external signals.

Carbon's prominence in living systems can be explained by the fact that:

carbon-based molecules can form long chains and rings.

The chromosomes in a homologous pair:

carry the same genes.

Scientific studies that compare patients with a disease to those without the disease are referred to as:

case-control studies

Which of the following pairs of processes encompasses the entire cell cycle?

cell division and interphase

The reaction sugar + oxygen = carbon dioxide + water + ATP is part of:

cellular respiration

Observational studies that follow a particular group of individuals over a certain time period are __________ studies.

cohort

Homologous chromosomes:

consist of a maternal and paternal copy of each chromosome.

The group of 18 bats that were "sham injected" represents a ________ group that experienced ________.

control; no change in the independent variable.

When a cell divides, it:

copies its own genetic information

Which of the following represents conducting an experiment?

dialing a telephone number

Two copies of the same gene on a single chromosome would indicate a(n) _________ had occurred.

duplication

Carbon is an example of an:

element.

Mendel's laws:

explain how genes are inherited.

Liver cells are different from heart cells of the same organism because these cell types:

express different genes.

The X chromosome in humans is:

found as a pair in females.

Although it seems contradictory, real science does not intend to "prove" a hypothesis to be true. This is because:

future experiments or discoveries may provide data that refutes the hypothesis.

Mendel used _______ as his research organism to study patterns of genetic inheritance.

garden peas

Mutations will affect the:

genotype, which may affect the phenotype.

When a germ cell has completed both rounds of meiosis, cells are created which are:

haploid, and each sister chromatid is in one of four different daughter cells.

Gene expression is:

highly variable; it changes for many different reasons throughout the life of a cell.

Individual water molecules orient toward each other because of the _______ bonds that form between them.

hydrogen

The two strands of a DNA molecule are held together by _________ bonds between their base pairs.

hydrogen

In making her morning tea, Dorothy drops a sugar cube into some hot water. She stirs the mixture but no longer sees the sugar cube at the bottom of her mug. Based on her observation of sugar dissolving in hot water, she can properly conclude that the sugar is:

hydrophilic.

When scientists generate a single informed, logical, and plausible explanation for a question and observations of the natural world, they are proposing a scientific:

hypothesis.

The endoplasmic reticulum (ER) is a single membrane continuous with the nuclear envelope and a series of interconnected sacs throughout the cell. Why might it be beneficial to the cell for the ER to be continuous with the nuclear envelope? It might be beneficial for the ER and nuclear envelope to be connected because it:

is easier for messages to get from the nucleus to the ER where proteins and lipids are made for the cell; this would require the use of less energy.

The smooth endoplasmic reticulum:

is the site where lipids destined for other cellular compartments are manufactured.

The significance of specific base pairing in DNA is that:

it provides a method for making exact copies of DNA.

Which of the following events in a cell would require ATP?

linking together amino acids to form a protein

Which of the following is associated with mitosis?

maintenance of chromosome number

DNA polymerase is used by the cell to:

make copies of a DNA sequence.

Gametes are produced by meiosis rather than mitosis because:

meiosis reduces the chromosome number so that zygotes produced will have one full genome.

Mendel's laws of segregation and independent assortment both have their biological basis in events that take place during:

meiosis.

Prokaryotes and eukaryotes are primarily distinguished by the absence or presence of internal:

membrane-enclosed organelles

Scientists repeat their experiments over and over again because they:

must make sure the results were not accidents and that they are repeatable.

A female carrier of the X-linked recessive gene for red-green color blindness will display a phenotype of:

normal color vision.

The boundary that surrounds the contents of the nucleus is the:

nuclear envelope.

DNA replication:

occurs before mitosis in the cell cycle.

During translation:

one mRNA molecule works with several rRNA molecules and many tRNA molecules to produce a protein.

During the process of ________, water diffuses across a semipermeable membrane from an area where water is more concentrated to an area where water is less concentrated (it moves along the water concentration gradient).

osmosis

Neighboring water molecules are held together with hydrogen bonds because:

partially negatively charged oxygen atoms and partially positively charged hydrogen atoms on separate water molecules are attracted to one another.

The reliability of primary scientific literature is strengthened by the ________ process, in which the work is examined by other leaders in the same field. For instance, a scientific paper examining the evolution of tetrapods would be reviewed by other evolutionary biologists and paleontologists.

peer review

Which of the following is LEAST likely to include unchecked bias when making scientific statements?

peer reviewed scientific journals

Living cells have an intact phospholipid bilayer that separates the cell from its external environment; this structure is commonly referred to as the:

plasma membrane.

A detective finds a miniscule spot of blood on a murder suspect's shirt. What method would the police lab be expected to use to get enough DNA from the blood droplet to perform DNA fingerprinting?

polymerase chain reaction (PCR)

A Punnett square is used to:

predict the genotypes and phenotypes of a genetic cross.

Experimentation is the primary, but not only, means use to verify or refute the ________ made by a hypothesis.

predictions

The sex of a human child is determined by the:

presence or absence of the Y chromosome.

The polymerase chain reaction (PCR) is used to:

produce many copies of a selected DNA sequence.

A human gene put into a plant cell will:

produce the same protein produced in a human cell.

The outcome of meiosis is the:

production of eggs and sperm

In photosynthesis, the carbon used to make sugars is:

provided by carbon dioxide.

Most inherited human genetic disorders are inherited as _________ alleles.

recessive

Glycolysis is an anaerobic process, indicating that the glycolytic reactions:

require no oxygen.

If DNA polymerase did not have the ability to proofread, then DNA replication would:

result in more mutations.

DNA fingerprinting is based on regions of DNA that are variable between individuals. Many of these differences between individuals produce no change in phenotype. This type of mutation is a(n):

silent mutation.

If a bottle of perfume was spilled in the corner of a large lecture hall, the students sitting near that corner of the room would very quickly smell the perfume. Over time, the students sitting in the far corner of the room would smell the perfume. What phenomenon has occurred to the perfume molecules that have entered the air?

simple diffusion

The Golgi apparatus:

sorts proteins and lipids and sends them to their final destination.

Which of the following cell types is produced by meiosis?

sperm

Once supported by a predictable experiment outcome, a scientific hypothesis:

still cannot be considered to have been proven true.

Following transcription, the:

strands of DNA bond back to each other.

A disaccharide consists of two:

sugars.

In Mendel's controlled mating experiments, the individuals produced by crossing two true-breeding parents are referred to as:

the F1 generation.

Which of the following does NOT represent a phenotype?

the alleles in a mouse that control hair color

Ice floats on water because:

the distance between water molecules in ice is greater than in liquid water.

In a genetic code, a codon is _______ bases long for ________.

three; all cell types

Which of the following does NOT take place in the nucleus?

translation

Whenever we _________, we are proceeding scientifically.

try to solve a problem by systematically evaluating the plausibility of various solutions

A replicated chromosome consists of _______ sister chromatids.

two

Which of the following is NOT a base found in DNA?

uracil

Oil and water do not mix well because:

water is polar and oil is nonpolar.

If a recessive allele causes a fatal disease that kills the affected individual before he or she can reproduce, why doesn't that allele quickly become extinct in the population?

The recessive allele is carried in the genome of the heterozygotes, who do not suffer from the disease.

If a genetic disorder is caused by a dominant allele, individuals with which of the following genotypes would be affected by the disorder?

AA and Aa

Which of the following statements describes the function of the light reaction in photosynthesis?

As electrons move through the light reaction, they release energy that is used to concentrate protons in the thykaloid.

Which of the following statements MOST accurately describes a selectively permeable membrane?

Certain solutes move freely across the membrane by simple diffusion, while others must be helped across by active or passive transport proteins; some substances are completely excluded from crossing the membrane.

A popular post on the Internet states that hugs "transfer energy" between participants, giving them an "emotional lift." Which of the following is a scientific approach to evaluating the claim of "energy transfer" during hugs? The hypothesis for the experiment would be as follows: if one person hugs another, the person receiving the hug will have more measurable energy after the hug.

First, develop a method of physically measuring the amount of energy available in a human being. Divide hundreds of subjects randomly into two groups, huggers and nonhuggers. The available energy in the individuals of each group would be measured, the individuals would then hug (or not), and then the energy levels are measured again. The experimenter should not know which group is the hugging or nonhugging group to avoid expectation bias. The experiment should be repeated numerous times before analyzing the data.

A scientist notices that a population of birds has decreased dramatically within one year and suspects that a newly introduced snail population may be affecting the bird population. Some individuals within the bird population eat snails, primarily, while other individuals avoid eating snails. Which of the following statements represents a prediction based on a well-constructed hypothesis for this observation?

If birds are affected by eating snails, then there will be a difference in the survival rate of birds that eat snails and those that avoid snails.

An individual claims to be able to detect the presence of graves in an old cemetery by using a "dowsing" or "divining" rod. The rod is a forked twig held in front of the individual as he walks across the cemetery. The "dowser" (person who is using the dowsing rod) claims that depending on which way the twig moves (up and down or side to side) he can determine if there is a grave there and the gender and age of the individual buried at that spot. Which of the following would NOT help evaluate if the dowser is a fraud?

It would help to know the dowser's age and affiliation with other dowsers.

The Krebs cycle produces:

NADH, ATP, and FADH2

What information in a pedigree would indicate a condition is likely dominant?

None of the affected individuals have unaffected parents.

What is the significance of crossing over?

The resulting gametes will have novel gene combinations compared to their parent cells' gene combinations.

Which of the following statements is true?

The scientific method or process can help people make informed medical and environmental decisions.

Autosomal dominant diseases are exhibited by anyone who carries at least one dominant allele for that gene. How is it that dominant lethal genes, such as the one that causes Huntington disease, can persist in a population?

These diseases usually take effect later in life after people have had children.

Which of the following is a similarity between photosynthesis and respiration?

They are both metabolic processes.

Is it important for scientists to communicate their results to follow scientists?

Yes. The quality and accuracy of the scientific work can be enhanced by input, further review, and possibly even repetition by other scientists working in the same field.

The solution with a pH of 3 is:

acidic.

A research team funded by a pharmaceutical company is studying the adaptation of grasshopper mice to the neurotoxic venom of scorpions in an attempt to determine how the mice's adaptation could be used as a possible solution to pain management in humans. This is an example of ________ research.

applied

Carbon atoms are bound to each other by __________ bonds.

covalent

Most inherited human disorders are the result of:

recessive mutations of genes located on autosomes.

A scientist is observing a membrane through which water and some small hydrophobic molecules can freely pass along a concentration gradient from high to low. However, some sugar molecules are too large to pass through the membrane either way without the assistance of passive transport proteins. Additionally, small Na + ions and some proteins can pass through the membrane against the concentration gradient, but both require the assistance of active transport proteins. What general type of membrane are they observing?

semipermeable

The pleiotropy that occurs when a single gene controls multiple skeletal traits in dogs, such as leg bone length and skull size, may be explained because:

the skeletal traits are related in the overall function of the dog.

Which of the following statements about cell division is correct?

It is the process by which organisms grow and maintain their tissues.

Plants and animals use different energy storage molecules, yet they both use the same mechanism to "burn" their stored energy. How can plants and animals both be successful, even though they "burn" different energy storage molecules?

The breaking of the chemical bonds of a storage molecule transfers energy, no matter what molecule is stored.

A scientist wishing to generate cancerous cells in vitro could subject the cells to which of the following procedures?

expose cells to chemicals that disrupt mitosis

Which of the following would be likely to move through a plasma membrane by simple diffusion?

water (H2O), carbon dioxide (CO2), and oxygen (O2)