W1 Questions

(Inheritance W1) You have received chromosome results back on the products of conception from your patient who has had a miscarriage. The karyotype is designated 92,XXXY. Which term below describes the karyotype?

(Inheritance W1) Polycystic kidney disease is a significant cause of renal failure that presents from early infancy to adulthood. Early-onset cases tend to affect one family member or siblings, whereas adult-onset cases often show a vertical pattern in the pedigree with affected family members in each generation. Which of the following provides the BEST explanation of these observations?

(Cytogenetics W1) A standard chromosome analysis is ordered for a child with heart defects, developmental delay, and an unusual facial appearance. The results are normal. A clinical geneticist colleague with whom you consult suspects Williams syndrome and recommends that fluorescent in situ hybridization (FISH) be performed on the patient's chromosomes using a probe for chromosome 7. Only one signal is seen for the chromosome 7 probe in each chromosome spread examined. Which of the following statements best summarizes the analyses?

(Cytogeneics W1) Which of the following features distinguishes meiosis from mitosis?

(DNA Replication W1) A one-year old child was treated in the emergency department for severe sunburn. According to the parents, the child had minimal sun exposure. No other abnormalities were noted in the physical exam except for freckling. You suspect:

(DNA Replication W1) A patient with Xeroderma pigmentosum has a defect in the XPA gene leading to a defect in nucleotide excision repair (NER). Cell extracts are prepared from this patient's cells and tested for the ability to perform nucleotide excision repair on DNA damage resulting from exposure to UV light. What outcome would you predict?

(DNA Replicatoin W1) The replication of genomic DNA is a tightly-controlled fundamental process. The beginning or initiation of chromosomal replication is initiated where?

(DNA Replication) Many drugs target the DNA replication process by altering the DNA template, inhibiting crucial enzyme activity, or blocking replication elongation. Drugs that inhibit bacterial Type II Topoisomerases (quinolone related) are very effective in antibacterial chemotherapy. What function of topoisomerase during replication are quinolones targeting?

(CSL) In systole, which valves are open and which valves are closed?

(Anatomy) Which type of imaging uses no radiation?

(Anatomy) Which one of the following types of anatomical planes would divide the body into a left half and a right half?

(Anatomy) A 15-year-old girl is suspected of having meningitis. To obtain a sample of cerebrospinal fluid by lumbar puncture, the tip of the needle must be placed in which of the following locations?

(Anatomy) The ventral (anterior) roots of the spinal nerves contain axons of somatic___________?

(Cell Bio) Small unrestrained particles such as proteins in an aqueous solution are in constant riotous motion due to thermal energy. Which of the following is a defining property of thermally-driven Brownian motion in the cell?

(Metabolism) During an enzymatically catalyzed reaction, what do the enzymes stabilize?

(Early Embryology) The amniotic cavity first forms by cavitation within which layer of cells?

(Embryology) Certain factors delay the transport of the cleavage stage embryo through the uterine tube (oviduct). This delay may cause which of the following?

(Embryology) Which of the following types of cells will specifically form the embryo?

(Genome organization) What functionally separates neighbouring Topologically Associated Domains (TADs) from each other?

(CSL) A heart murmur is caused by:

(Biochem) Please use the attached image to answer the following: Some amino acids have ionizable side chains. Which amino acid would have the titration curve shown in the attached figure?

(Biochem) The concentration of H+ ions in a solution at pH 6 compared to pH 7 is:

(Biochem) Although all protein structures are unique, there are common structural building blocks that are referred to as regular secondary structures. Some proteins have a helices, some have B sheets, and still others have a combination of both. Which of the features below is most responsible for enabling proteins to have these common structural elements?

(Genome Organization) The Philadelphia chromosome was a landmark because it was the first consistent chromosome abnormality found in any kind of malignancy. What kind of chromosomal rearrangement creates the Philadelphia chromosome?

In judging the quality of a physician, which of the following factors is noted as being most important to patients?

A physician's active listening is a key part of communication between physician and patient. Active listening includes accurately summarizing the patient's story and responding empathetically. Another indicator of active listening is:

(Genetic Variation) In reference to genetic variation, a mutation is best characterized as:

(Genetic Variation) Your 8 y.o. patient and his parents undergo genome sequencing. The report shows that your patient has a variant, c.100delAG in a gene associated with his phenotype. This variant is not found in either of his parents nor in any population database or the literature. What is your best interpretation?

(Inheritance and pedigree) Use the attached image to answer the following: The attached pedigree shows segregation of a rare genetic disease through a family. Filled in symbols represent family members with the disease phenotype. What is the MOST LIKELY mode of inheritance?

(Metabolism) Please use the attached image to answer the following: In the attached graph of an enzyme-catalyzed reaction, what is indicated by the letter "X"?

(Protein Structure) Of the following amino acids, which one can be phosphorylated on its side chain?

(Proteins) Studies conducted with a lysozyme mutant that contains an Asp->Asn change at position 52 and a Glu->Gln change at position 35 exhibited almost a complete loss in enzymatic activity. What is the most likely explanation for the decrease in enzyme activity in the mutant?

(Proteins) Polypeptides are synthesized from amino acid building blocks. The condensation reaction between the growing polypeptide chain and the next amino acid to be added involves the combined loss of ________________ from the newly formed peptide.

(Pedigree) Use the attached image to answer the following: Attached is the pedigree of a family in which a genetic disease is segregating. Affected family members are in black. The MOST LIKELY mode of inheritance is: