Biology Exam

__________ has the ability to target cells of the body that are infected with pathogens, while also responding to any pathogens that are free in the blood or interstitial fluid of the body.

Adaptive immunity

Which fo the following is only true of RNA, but not DNA?

Adenine pairs with uracil

Which of the following ways is how the flu virus may impact body systems?

All of the above

Which fo the following statements about B cells is true?

All of the answer choices are correct

During previous flu season, small variations in the influenza virus resulted in the immune system's inability to full recognize and respond to flu exposure. As a result, the vaccine was less than 30% effective. This is an example of _____.

Antigenic Drift

When two different forms of a virus infect the same cell, the host cell may manufacture viral particles from both viruses to reassemble them into a new form of virus. This process is called ____.

Antigenic shift.

The DNA of cats and dogs is much more similar than the DNA of cats and hamsters. Why is that?

Cats and dogs have a common ancestor that is more recent than the common ancestor of cats and humans.

Select all of the following statements Do not describe the structure of of a molecule of DNA

Contains Ribose sugar

In most organisms the flow of information is from

DNA RNA then protein

Which of the following unzips the double helix of DNA during DNA replication?

DNA helicase

Which process best describes how viruses may originate in animals and eventually be transmitted to humans, causing outbreaks?

Evolution

Sex-linked conditions are more common in men than in women because men acquire two copies..

False

Sickle cell disease is a recessive disease. This means that two individuals without the disease cannot have a child with the disease.....

False

To transcribe something is to make an identical copy, i.e., if the original is DNA, the transcribed copy is also DNA.

False

DNA microarrays use enzymes to convert mRNA obtained from the cell into cDNA. This cDNA is hybridized with known DNA from specific genes isolated from the organism. If hybridization occurs, what does this mean?

It means the cDNA has bound to complementary DNA on the microarray, indicating that the corresponding gene is being expressed in the cell.

Images of unreplicated chromosomes that allow researchers to organize and identify each chromosome, as well as missing or extra chromosomes is called a(n) _____.

Karyotype

The cycle of viral infection that will rapidly result in the death of a bacterial cell is called the _____ cycle.

Lytic

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best explains what happened?

Only triazine-resistant weeds survived and reproduced, so each year more pigweed was triazine-resistant.

In addition to excessive bleeding, persons with hemophilia may have excessive bruising, pain and swelling in the joints, vision loss, anemia, or neurological problems. This is a result of the effects of a single gene loss and is called

Pleiotropy

Meiosis is different from mitosis in that meiosis.

Results in four haploid daughter cells that are genetically diverse, whereas mitosis results in two diploid daughter cells that are genetically identical.

Meiosis proceeds different in males compared to females. Which of the following best describes one of those differences?

Spermatogenesis results in the production of four haploid sperm cells and oogenesis results in the production of a single haploid egg cell.

CRISPR may work to treat sickle-cell disease by

Targeting faulty portions of the hemoglobin gene within the genome of cells and removing and replacing those portions with normal sequences of nucleotides.

Which of the following best describes how the flu virus may impact the respiratory system?

The proteins produced by the virus interfere with ability of epithelial cells to move materials in and out of lung tissue, resulting in fluid buildup in the lungs.

which of the following statements DOES NOT relate to natural selection

The variations in a population make no difference in terms of reproductive success.

Which of the following is true of chromosomes in a cell undergoing cell division?

They have histones bound to them.

During Gamete formation, genes segregate from each other so that each sperm and egg only receive one allele for a specific gene.

True

two parents with type A and type B blood have a child with type AB

Type A is codominant with type B so both alleles are expressed equally

During gene therapy, bone marrow stem cells are removed from the individual. What must happen to those cells before they are injected back into the individual?

Viruses act as vectors to carry the normal gene into the genome of the stem cells.

A population of birch trees is present on the side of a mountain and is preyed upon by beetles that burrow into bark. Which of the following trees would be the most fit?

a tree that has thicker bark

In land mammals, the pelvic girdle is the point where the leg bones attach to the rest of the skeleton. Whales also have a small pelvic girdle. This would be an example of what type of evidence for common descent?

a vestigial structure

Antiviral medications target specific stages of the viral life cycle. Which of the following is not a stage of the life cycle that is targeted?

maturation

Which of the following is the correct sequence of how an animal is built?

meiosis-fetilization-zygote-embryo

Y-linked genes include a gene that produces hairy ears. A male with hairy ears should pass this trait

only to his sons

When he influenza virus enters into an epithelial cell within the respiratory tract, the infected cell responds by

posting antigens on its cell surface, acting as a flag for the cytotoxic T cells to destroy it.

Familial Hypercholesterolemia is a disease that is incompletely dominant. This means that

the dominant allele does not fully mask the recessive allele, so an intermediate phenotype is displayed.

What is the role of the enzyme ligase in DNA replication?

to join together fragments of newly synthesized DNA to form a seamless strand

How does the body recognize "self" cells compared to "nonself" cells?

"Self" cells are marked by glycoproteins called major-histocompatibility complexes (MHCs).

Two genes are responsible for coloration of the amphibian

1 Black and spotted : 1 Black and unspotted : 1 blue and spotted : 1 blue and unspotted

cystic fibrosis is caused by aellele F which is reccessive. Whats the % their 2nd is will develop cycstic

25

cystic fibrosis is caused by aellele F which is reccessive. Whats the % their first child is will develop cycstic

25

During the human life cycle, the fertilization of an egg by a sperm results in.

A diploid zygote

Which of these is an example of diversifying selection?

A population of moths with white and grey forms lives in a forest containing trees with light and dark bark.

All viruses are made up of two components. What are they?

A protein capsid and genetic material, in the form of either RNA or DNA.

CRISPR was discovered.

Accidentally, by scientists working with bacteria in the food industry. They were looking for ways to make cheese and yogurt production more effective.

Which of the following statements is true about the production of the influenza vaccine?

All three methods describe different approaches used to make flu vaccines.

Which of the following is an example of non-evolutionary change in population?

An increase in the number of people diagnosed with lung cancer

Why do chromosomes resemble the letter X when viewed during metaphase?

Because there are two sister chromatids joined at a point in the middle (the centromere).

A method of genome editing that uses the Cas9 enzyme to identify...

CRISPR

A method of genome editing that uses the Cas9 enzyme to identify and cut specific nucleotides from the genome is called _____.

CRISPR (clustered regularly interspaced short palindromic repeats).

A certain species of butterfly varies in color from white to dark blue. The birds found in the same area feed on the white or lightly colored butterflies, leaving butterflies that are darkly colored. This is an example of what type of selection?

Directional Selection

what is the name of the enzyme that fits new complementary DNA Nucleotides into the new strand

Dna POlymerase

the method of determining the exact nucleotide order of sequence of DNA is called____

Dna sequencing

Which of the following types of cells would a flu virus most likely target as the means of entry into the body?

Epithelial cells lining the respiratory system.

which of the following is considered to be the unifying theory of BIO

Evolution

which of the following traits are considered to be inheritable

Eye color

Viruses only infect humans

False

Which of the following statements about components of the flu vaccine and their intended function is true?

Formaldehyde is used to inactivate toxins from the virus or bacteria that may have been present during production.

Which of the following is the most effective means of treating or even curing sickle-cell disease?

Gene Therapy

Which of the following best describes the definition of a gene?

Genetic information that produces a product, either proteins or RNA.

Which of the following is an example of microevolution?

HIV evolved resistance to antiviral medications.

According to the theory of common Descent each species on earth today should?

Have a single common ancestor

Which the following is an example of gene therapy?

Infecting a cystic fibrosis patient with a virus carrying a working copy of the healthy gene.

There are three major parts within DNA nucleotide. Of these three, which is responsible for the storage of genetic information?

It's four nitrogen bases.

Which of the following does not enhance genetic diversity?

Mitosis

Which of the following is/are true about natural selection?

On average, it favors the survival of individuals that have adaptive characteristics.

RNA polymerase has several jobs during the transcription process. Which of the following is not a job that it performs?

RNA polymerase edits the mRNA strand by removing some sections and splicing together remaining sections.

Sickle-cell disease results in malformed hemoglobin molecules. Which cell type contains millions of hemoglobin molecules per cell?

Red Blood cells

Sickle cell disease causes hemoglobin proteins to become altered. What direct effect does this have on red blood cells?

Red blood cells become sickle-shaped, clumping up and blocking blood flow in capillaries.

Which of the following statements accurately describes the impacts of sickle-cell disease on the body?

Red blood cells clump up, blocking capillaries within the alveoli, resulting in acute chest syndrome, marked by pain, fever, and shortness of breath.

The "highly specific molecular scissors" that cut DNA are called?

Restriction enzymes.

Duplicated chromosomes result in two sister chromatids that are held together by a centromere. Which of the following statements best describes the location of genes along these sister chromatids?

Sister chromatids have identical alleles that are located in the same place along each sister chromatid.

In rabbits the color of the fur and length of the legs...

So the fraction of the offspring of the cross BbLl X BbLl that will be expected to have white fur and long legs is 3/16.

If the DNA contained in the chromosomes of an organism is similar to an instruction manual, then what are the genes "instructing" the cell to do?

Synthesize specific proteins from amino acids

Bat wings are homologous to the front legs of cats. What does the term "homologous" mean in this context?

The common ancestor of bats and cats had a limb with a bone structure similar to that found in cat and bat wings.

How do fossils support the theory of common descent?

They are a record of at least some intermediate types of organisms and thus document the process of evolution.

Viruses highjack the metabolic machinery of a host cell.

True

Viruses vary in their shapes and the types of cells they infect

True

Sickle-cell disease is a recessive genetic disease. This means.

Two copies of the recessive allele must be present in order for the disease to be expressed.

Monozygotic twins are a result of

a single fertilized egg that splits in two.

Sickle cell disease is a disorder that is caused by

a single mutation on a single gene.

Variations in genes are called _____. Examples of these variations include eye color. There are blue eyes, green eyes, brown eyes, and several combinations of these

alleles

Where within the lungs does gas exchange occur?

alveoli

The activities of macrophages

are part of the nonspecific response against disease and stimulate phagocytic neutrophils.

What is the correct sequence of events in viral reproduction?

attachment, penetration, biosynthesis, maturation and release

What is the correct sequence of events in viral reproduction?

attachment, penetration, biosynthesis, maturation, and release.

Which of these is the best description of a virus?

chemical complexes of RNA or DNA protected by protein shell

Segments of DNA that contain instructions for making either proteins or RNA molecules that regulate proteins are called ____.

genes

In order to infect a cell, a virus must

have a special protein on its surface that can interact with a protein on the surface of the host cell.

Down syndrome is a conditon caused by ____ of chromosome 21 during meiosis

i think Nondisjunction

If a dark blue-colored flower crossed with a white-colored flower produced light blue-colored flower offspring, then it's most likely a case of

incomplete dominance

When a population of organisms is evolving, what can you be sure is happening?

its changing

Mendels experiments led him to the conclusion that individuals have two factors for each trait that separate during gamete formation...

law of segregation

The cycle of viral infection in which the viral DNA is integrated into the host's DNA is called ___ cycle.

lysogenic.

Antigens are

molecules produced by white blood cells that stimulate other white blood cells, namely T cells.

If one person in a population has two different alleles of a particular gene and it's known that other people in the population have yet another different allele of this gene, then this is an example of

multiple alleles

Polygenic traits display phenotypes that

represent a continuous range within the population.

Dna replication is considered to be....

semi-conservative

In humans, the sex of the offspring is ordinarily determined by the

sex chromosomes carried by the sperm cell.

Mendel crossed pea plants

the law of independent assortment

Imagine that a mutation in a DNA molecule results in the codon CCU being changed to CCC. Both of these codons code for proline. This is an example of

the redundancy of the genetic code.

Birds and insects both have wings, but we do not consider this similarity as evidence of relatedness because

the wings are not homologous structures with a common ancestral origin.

Evolution is referred to as a theory because

there is overwhelming evidence to support it from many areas of biology.

Giant viruses are challenging the historical notion that viruses are nonliving things. What characteristic do giant viruses possess that make scientists think twice about their classification?

they have the ability to manufacture their own proteins without the help of a host cell

Evolution is a very controversial idea among scientists.

False

Which of the following structures are associated with the immune system?

Thymus, spleen, red bone marrow, lymph nodes

Which of the following is a characteristic of all living things?

All living things maintain a constant internal environment.

Research for the universal flu vaccine tends to focus on

Core proteins, as they do not muytate as rapidly as H and N spikes.

Any individual organism has the potential to evolve if its given enough time and possesses a mechanism to generate variation

False

During a gamete formation genes segregate from each other so that each sperm and egg only receive one allele for a specific gene

False

About 12,000 years ago, a mass extinction event occurred and 75% of the world's large mammal species were eliminated. While a small number of cheetahs managed to survive and restore the world's population of cheetahs, this event caused an extreme reduction of the cheetah's genetic diversity. Based on the principles of natural selection, which of the following is a consequence of their reduced genetic diversity?

Cheetahs have very little heritable variation, which will make it difficult for them to adapt as the environment changes.

Susie is pregnant with her first child. Because of her advanced maternal age and a family history of various genetic disorders, her doctor has recommended genetic testing to ensure her offspring is healthy. Her doctor places a long thin suction tube through her vagina into the uterus, where it obtains fetal cells from the chorion of the developing embryo. These cells are then sent off for testing. What is this type of procedure called?

Chorionic Villus Sampling (CVS).

homologous chromosomes

Chromosomes found only in diploid cells, that are the same size, the same shape, have the same instructions or genes, but not necessarily the same information or alleles.

During prophase I of meiosis, genetic information is exchanged between two homologous chromosomes, resulting in new combinations of alleles. This process is called _____.

Crossing - Over.

Which kind of T cell is most important in the removal of virally-infected cells from the body?

Cytotoxic T Cells

Mendel's experiments led him to the conclusion that individuals have two factors for each trait that separate during gamete formation, resulting in gametes with one factor for each trait. In addition, fertilization results in a new individual with two factors for each trait again. He referred to this as the _____.

Law of segregation.

CRISPR may work to treat sickle-cell disease by.

Targeting faulty portions of the hemoglobin gene within the genome of cells and removing and replacing those portions with normal sequences of nucleotides.

A city was intensively sprayed with DDT to control houseflies. The number of houseflies was immediately greatly reduced. Each year thereafter, the city was sprayed again, but the flies gradually increased in numbers until 10 years later, when they were almost as abundant as they were when the control program began. Which of the following most likely explains this?

The DDT killed most flies the few that were already naturally resistant surived and passsed the resistance on to their off spring

Once in the respiratory tract, the flu virus targets cells based on specific glycoproteins on their surfaces. How does the virus gain entry into the target cell?

The N spikes of the influenza virus help break down the plasma membrane of a cell, allowing entry of the virus into the cell.

Once in the respiratory tract, the flu virus targets cells based on specific glycoproteins on their surfaces. How does the virus gain entry into the target cells?

The N spikes of the influenza virus help break down the plasma membrane of a cell, allowing entry of the virus into the cell.

Why are new flu vaccinations required for each new flu season?

The flu virus mutates frequently enough that last year's vaccination will no longer target currently circulating flu strains.

A trait that confers fitness in one environment might make an organism less able to to survive and reproduce in another.

True