Gen and Med Quiz Review

Over the past 10 years we have learned a great deal about cancer through genomics projects such as The Cancer Genome Atlas (TCGA) Project. Which one of the following is FALSE? a. Chromothripsis can occur in >50% of soft-tissue cancer types. b. Most cancers are caused by 2-8 sequential alterations over 20-30 years. c. All breast cancers show the same oncogenic signature. d. ~140 genes are known whose mutations drive cancer. e. Every individual tumor is distinct with regard to genetic alterations, but pathways affected in different tumors may be similar.

c. All breast cancers show the same oncogenic signature.

Hemophilia is an X-linked recessive condition characterized by excessive bleeding with injury. A woman who carries the gene but is not affected marries a normal man. What proportion of the couple's sons is expected to have hemophilia? a. 50% b. 75% c. 0% d. 100% e. 25%

a. 50%

During DNA replication, one DNA strand is copied to make a new DNA molecule composed of two DNA strands. This new DNA molecule contains a. 50% of the parent DNA. b. none of the parent DNA. c. 25% of the parent DNA. d. 75% of the parent DNA. e. 100% of the parent DNA.

a. 50% of the parent DNA.

What process is illustrated below? a. The formation of gametes via meiosis. b. Fertilization c. The formation of gametes via mitosis d. The formation of single stranded RNA. e. The replacement of damaged cells

a. The formation of gametes via meiosis.

A carrier of a genetic disorder who does not show symptoms is most likely____________ to transmit it to offspring. a. heterozygous for the trait and able b. None of these answers are correct. c. homozygous for the trait and unable d. homozygous for the trait and able e. heterozygous for the trait and unable

a. heterozygous for the trait and able

The 3-D structure of RNA is very different from DNA. Why? Choose the one FALSE statement. a. phosphodiester linkages between the nucleotides. b. the 2'-hydroxyl (-OH) makes RNA more chemically reactive. c. RNA has the nitrogenous base uracil. d. the base pairing prevents formation of an anti-parallel double helix. e. a series of ribonucleotides connected by covalent bonds

a. phosphodiester linkages between the nucleotides.

Why is the inheritance of so many traits difficult to explain using only Mendel's view of genetics? a. Failures in the predictive power of Mendel's ideas about inheritance are artifacts that reflect our incomplete understanding of the organisms under study. b. Mendel was correct for the traits he investigated, but his principles must be extended (not discarded) to explain more complex patterns of inheritance. c. Mendel did not know about chromosomes, so he could not have been expected to describe the laws of inheritance. d. Mendel's laws of segregation and independent assortment apply only in a limited set of cases in sexually reproducing organisms. e. Mendel worked with peas, not humans, and the genetic principles that operate in a simple organism like a pea plant cannot be applied to an organism as complex as a human.

b. Mendel was correct for the traits he investigated, but his principles must be extended (not discarded) to explain more complex patterns of inheritance.

Which of the following was a novel deduction that Watson and Crick were able to make about DNA based on Rosalind Franklin's X-ray diffraction data, i.e., Photo 51? a. DNA was composed of nucleotides. b. The consistent width of DNA meant that purines must base-pair with pyrimidines. c. The amounts of A = T and C = G is the same in all DNA molecules. d. Chromosomes are the locations of our genes encoded by sequences of nucleotides. e. None of the choices stated

b. The consistent width of DNA meant that purines must base-pair with pyrimidines.

The goals of the Vertebrate Genome Project 2021 include the following except one. Identify the one FALSE choice. a. To develop new algorithms for near complete genome assemblies. b. To understand cancer and rare genetic diseases in animals. c. To reconstruct common ancestor genomes. d. To define the genomics of vocal learning, flight, loss of limb, and aquatic/terrestrial adaptations. e. To generate near error-free reference genome assemblies of 70,000 extant vertebrate species.

b. To understand cancer and rare genetic diseases in animals.

Which of the following statements about genetic diversity over two generations is FALSE? a. Genetic diversity is enhanced by homologous chromosomes in meiosis that carry different versions of genes. b. Genetic diversity is enhanced by crossing over during prophase I of meiosis. c. Genetic diversity is enhanced by random fertilization. d. Genetic diversity is enhanced by mutations. e. Genetic diversity is enhanced by independent orientation of chromosomes at metaphase I during meiosis.

d. Genetic diversity is enhanced by mutations.

Which of the following is true about double-stranded DNA? a. Adenine and uracil are present in equal amounts. b. It is shaped like a triple helix. c. The two strands are identical. d. Its 3-D conformation is quite different from RNA's 3D conformation. e. Adenine and cytosine are present in equal amounts.

d. Its 3-D conformation is quite different from RNA's 3D conformation.

What is the correct order of the stages of Mitosis? a. Prophase, Metaphase, Telophase, Anaphase, Cytokinesis b. Telophase, Prophase, Metaphas, Cytokinesis, Anaphase c. Cytokinesis, Prophase, Metaphase, Telophase, G1. d. Prophase, Metaphase, Anaphase, Telophase, Cytokinesis e. Metaphase, Prophase, Anaphase, Telophase, Cytokinesis

d. Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

During which stage of meiosis does crossing over and formation of tetrads occur? a. metaphase I b. interphase II c. interphase I d. prophase I e. prophase II

d. prophase I

The results of the Human Genome Project have changed how we view our DNA/genome. What were the major surprises? Identify the one FALSE statement. a. There is repetitive DNA sequences between the genes. b. Protein-encoding genes make up ~1.5% of our genome. 98.5% is noncoding DNA. c. Gene control sequences (promoters, enhancers, microRNA) make up 24% of the human genome. d. There are millions of transposable elements that are repeated throughout the genome. e. A single individual's DNA was sequenced; therefore little was initially learned from it.

e. A single individual's DNA was sequenced; therefore little was initially learned from it.

The Hershey-Chase experiments in 1952 were important because they showed that a. the X-ray diffraction data showed a double helix. b. proteins were the hereditary molecules. c. the concentrations of [A] = [T] and [C] = [G]. d. DNA was the hereditary material. e. a nuclear extract was made up of H, O, N, and P with a unique ratio of N to P.

d. DNA was the hereditary material.

Scientists commonly choose white blood cells that are going through mitosis to prepare karyotypes. Why? a. More cells are in mitosis than any other stage of the cell cycle, making it easier to obtain mitotic cells for study. b. Cells in mitosis contain the greatest number of chromosomes, thus providing more material for study. c. Cells in mitosis have the fewest chromosomes, thus simplifying karyotype analysis. d. Karyotypes are based on chromatin and not chromosomes. e. Chromosomes are more condensed during mitosis than interphase.

e. Chromosomes are more condensed during mitosis than interphase.

A researcher treats cells with an inhibitor that prevents DNA synthesis from starting. This treatment would trap the cells in which stage of the cell cycle? a. cytokinesis b. G2 c. mitosis d. G0 e. G1

e. G1

Transfer RNA molecules a. add a cap and tail to the mRNA molecules. b. mediate the conversion of genetic information into protein sequences. c. carry mRNA molecules from the nucleus to the cytoplasm. d. enable Okazaki fragments to be joined. e. None of these answers are correct.

b. mediate the conversion of genetic information into protein sequences.

A mouse that has the genotype AANnPpzz will have the same phenotype as a mouse with which genotype below. Note that the uppercase alleles A, N, P, and Z are dominant. a. AaNNPPzz b. AANNPPZZ c. AaNNPpZz d. AANnppZz e. AAnnPPZz

a. AaNNPPzz

The Central Dogma in molecular biology refers to a. DNA to RNA to Protein. b. RNA to DNA to RNA. c. RNA to Protein to mRNA. d. Protein to RNA to DNA. e. None of these choices.

a. DNA to RNA to Protein.

"Count Me In" was established in 2018 as a nonprofit organization committed to advancing patient-partnered research with support from the Broad Institute, Emerson Collective, Dana-Faber Cancer Institute, and the Biden Cancer Initiative. Choose the one FALSE statement. a. Only through very large data sets can identification of mutations common to a particular cancer group be correlated with a specific treatment approach. b. Count Me In is a government supported initiative. c. Patient data included genomic data, saliva, blood, and stored tumor samples, and clinical histories. d. In this initiative, there is an increased focus of including men and women, people of all ethnicities, and people of color. e. Each cancer has a specific oncogenic signature, and therefore the medical treatment must be tailored for the patient.

b. Count Me In is a government supported initiative.

In 1990, Mary Claire King identified the gene associated with increased risk of breast cancer. Based on her initial work, we now know the following except one FALSE statement. a. Dr. King developed the BROCA diagnostic test in 2015, which can screen for 50-60 genes in patients suspected of a predisposition to hereditary cancers. b. Dr. King argued before the Supreme Court that naturally occurring DNA should be patent eligible. c. BRCA1 and/or BRCA2 mutations increase the risk for breast cancer. d. BRCA1 is localized to chromosome 17. e. BRCA1 and BRCA2 encode for proteins involved in DNA repair.

b. Dr. King argued before the Supreme Court that naturally occurring DNA should be patent eligible.

James Allison and Tasuku Honjo were awarded the 2018 Nobel Prize in Physiology or Medicine because of which one of the following? a. They identified key proteins that are normally responsible for turning off sickle cell anemia. b. They identified key proteins on T cells, called immune checkpoint proteins, that were normally responsible for turning off activated T cells. c. They developed a new CRISPR strategy to fight cancer. d. They were responsible for the shotgun method of sequencing. e. They patented the BRCA1 and BRCA2 genes and developed a diagnostic test for breast cancer.

b. They identified key proteins on T cells, called immune checkpoint proteins, that were normally responsible for turning off activated T cells.

Cells with two of each kind of chromosome are described by the term a. triploid b. diploid c. haploid d. tetraploid e. polyploid

b. diploid

Most genetic disorders of humans are caused by a. multiple alleles. b. drinking during pregnancy. c. a mutation that occurs in the egg, sperm, or zygote. d. dominant alleles. e. recessive alleles.

e. recessive alleles.