Medical biology
Medical biology
Питань: 53
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Питання 1 з 53
Питання 1
A man was brought to the hospital in a severe condition: facial edemas, myalgia, high temperature, and respiratory distress. History-taking revealed that the patient’s family regularly consumes untested pork. What helminth can be the cause of such symptoms?
Питання 2
The cell was exposed to mutagenic factor which resulted in DNA molecule losing 2 nucleotide pairs. What type of mutation occurred in the DNA?
Питання 3
An experiment has demonstrated that after exposure to ultrav radiation the dermal cells of the patients with xeroderma pigmentosum are slower to restore the native DNA structure than they are in the healthy individuals due to deficiency of the DNA repair enzyme. What enzyme takes part in the repair process?
Питання 4
After dehelmintization, a 35-year-old man passed a 3.5 m tapeworm during a bowel movement. A stool examination reveals scolex with four suckers and hooks. Mature proglottids are static with up to 12 primary uterine branches. Which of the following is the most likely diagnosis?
Питання 5
Medical examination in an army recruitment center detected a 15-year-old boy with tall stature, eunuchoid body proportions, gynecomastia, and female pattern of pubic hair growth. The boy has fat deposits on the thighs, no facial fair growth, high-pitched voice, and below average IQ. He was diagnosed with Klinefelter syndrome. What karyotype corresponds with this disease?
Питання 6
A molecular biologist studies various molecules. One of them is a polymeric molecule essential in various biological roles in coding, decoding, regulation, and expression of genes. It is a helical single-stranded molecule folded onto itself. Which of the following molecules is being studied?
Питання 7
During cell division, DNA replication occurs by a signal from the cytoplasm, and a certain portion of the DNA helix unwinds and splits into two individual strains. What enzyme facilitates this process?
Питання 8
A patient consulted a physician about chest pain, cough, fever. Roentgenography of lungs revealed eosinophilic infiltrates that were found to contain larvae. What kind of helminthiasis are these presentations typical of?
Питання 9
A person with the fourth blood group (genotype IAIB) has in erythrocytes both antigen A controlled by allele IA and antigen В controlled by allele IB. This phenomenon is an example of the following gene interation:
Питання 10
When examining a female patient a doctor observed the following: misshapen auricles, elevated palate, teeth growth disorder; mental retardation; no disruption of reproductive function. Provisional diagnosis is the "super woman"syndrome. Point out the karyotype of this disease.
Питання 11
In some areas of South Africa many people have sickle cell disease characterized by red blood cells that assume an abnormal sickle shape due to the substitution of glutamic acid for valine in the hemoglobin molecule. What is the cause of this disease?
Питання 12
In the perianal folds of a 5-year-old girl mother found white worms causing itch and anxiety, and took them to the laboratory. The study revealed white filament-like helminths 0,5-1 cm long, with pointed, sometimes twisted, ends. What diagnosis can be made?
Питання 13
A girl provisionally diagnosed with Turner syndrome made an appointment with a genetic consultancy. What genetic method of diagnostics can confirm this diagnosis?
Питання 14
Ribosomes are the organelles that bind amino acid residues into a polypeptide chain. The number of ribosomes in the cells of different organs varies and depends on the function of the organ. What organ has the highest ribosome count in its cells?
Питання 15
Replication is one of the reactions of matrix synthesis. What new molecule is formed from a DNA molecule in the process of replication?
Питання 16
During histologic examination of the skeletal muscle specimen, the investigator discovers an organelle that has 2 membranes: smooth outer membrane and internal, that forms multiple ridges of visible folds (crysts). Which of the following is the most likely function of this structure?
Питання 17
A 34-year-old woman goes into labor at 38 weeks. After several hours of labor a male infant is born with fever, hydrocephalus, hepatosplenomegaly, jaundice, bilateral chorioretinitis and cerebral calcifications. Which of the following protozoan infections is the most likely cause of the infant's condition?
Питання 18
A molecular-level-process of spontaneous passive transport of water- soluble molecules across a cell membrane is modeled. The molecules move across cell membranes from an area of higher concentration toward an area of lower concentration via specific transmembrane integral proteins. This transport does not directly require chemical energy from ATP hydrolysis. Which of the following transport mechanisms is most likely mentioned?
Питання 19
A 36-year-old male comes to the dental office for extraction of the tooth. Two weeks after the procedure is performed, the stratified squamous epithelium regenerates at the site of extraction. Which of the following organelles is most likely involved in the mucosa regeneration?
Питання 20
Healthy parents with unremarkable family history have the child with multiple developmental defects. Cytogenetic analysis revealed the trisomy 13 in the somatic cells (Patau syndrome). What phenomenon has caused the defects?
Питання 21
Examination of an 18-year-old girl revealed the following features: hypoplasia of the ovaries, broad shoulders, narrow pelvis, shortening of the lower extremities, «sphinx neck». Mental development is normal. The girl was diagnosed with Turner’s syndrome. What kind of chromosome abnormality is it?
Питання 22
Cells of healthy liver actively synthesize glycogen and proteins. What organelles are the most developed in them?
Питання 23
The parents with normal hearing have two daughters and a son, who are congenitally deaf. Their other 5 children are healthy. What is the pattern of deafness inheritance in this case?
Питання 24
Infectious diseases are treated with antibiotics (streptomycin, erythromycin, chloramphenicol). They inhibit the following stage of protein synthesis:
Питання 25
An 18-year-old girl comes to her physician with concern about her health because she has not achieved menarche. She denies any significant weight loss, changes in mood, or changes in her appetite. She mentions that her mother told her about mild birth defects, but she cannot recall the specifics. Past medical history and family history are benign. On physical examination, the patient is short in stature, has a short and webbed neck and wide chest. Staining of buccal smear reveals absence of Barr bodies in the nucleus of epithelial cells. A urine pregnancy test is negative. Which of the following genetic disorders is the most likely cause of this patient's condition?
Питання 26
A 39-year-old man comes to the doctor with complaints of chest pain and cough with occasionally blood-streaked sputum. He does not have increased temperature or night sweating and his history is insignificant for smoking or alcohol abuse. However, he mentions visiting a few weeks ago a relative who
owns a sheep farm. Radiographic examination shows a cyst in the left lower lobe with calcification. Casoni test is positive. Which of the following
organisms is the most likely cause of this patient's condition?
Питання 27
A 2-year-old boy is diagnosed with Down syndrome. What chromosomal changes may be the cause of this disease?
Питання 28
A team of medical students is performing research on phases of cell cycle. During one of the mitotic phases the cell is nearly done dividing, the chromosomes decondense and two nuclei begin to form around them. Which of the following phases most likely takes place in the cell?
Питання 29
Diphtheria toxin is a potent inhibitor of protein synthesis in eukaryotes. What is its molecular mechanism of action?
Питання 30
A person with suspected liver abscess has been admitted into the surgical department of a hospital. This person was on a business trip in one of the African countries for a long time and repeatedly had been suffering from acute gastrointestinal disease. What protozoan disease is likely in this patient?
Питання 31
Genealogical analysis of a family with a hereditary pathology of optic nerve atrophy has determined that this medical condition is passed on only by the mothers, both girls and boys can be affected, and the sick father does not pass on the disease to his daughters or sons. What type of hereditary disease is it?
Питання 32
In an experiment, despiralization of the DNA molecule was disrupted in an animal cell. What processes will primarily stop occurring in this cell?
Питання 33
Histones are small basic proteins, bound to DNA in chromatin. They contain numerous positively charged amino acid residues, which ensures their strong bond with the acidic groups of DNA. Name the most common amino acids in histones.
Питання 34
The molecule of immature mRNA (pro-mRNA) contains more triplets than there are amino acids in the synthesized protein, because translation is normally preceded by:
Питання 35
Transcription is the reaction of mRNA matrix synthesis on DNA matrix. Name the stages of transcription.
Питання 36
In some diseases of the nervous system, damage with chromatolysis phenomena can be observed in the neurocytes. What intracellular metabolic processes become disturbed in the neurons?
Питання 37
Examination of a patient detected accumulation of sphingomyelins in the cell lysosomes of the patient's liver, spleen, lungs, bone marrow, and brain, caused by the lack of sphingomyelinase enzyme. What pathology is most likely in this patient?
Питання 38
Amniocentesis revealed that the karyotype of the fetus was 45, X0. What syndrome is it?
Питання 39
In an experiment, despiralization of the DNA molecule was disrupted in a mammalian cell. What process will become primarily disrupted in this cell as a result?
Питання 40
What group of organisms has nucleoids circular DNA molecules that form chromosomes with a simple structure (no histones)?
Питання 41
What process allows producing different mRNAs from a single primary transcript?
Питання 42
Karyotyping detected 47 chromosomes (3 copies of chromosome 13) in a newborn child with multiple defects of the skull, limbs, and internal organs. What syndrome can be characterized by such pathological changes?
Питання 43
In a certain section of a chromosome, the genes were arranged in the following sequence: abcdef Due to a mutagenic factor, a rearrangement occurred in this section, causing the following sequence of the chromosomes: abedcf. What type of mutation has occurred in this case?
Питання 44
A man has been diagnosed with a hereditary disease that manifests as extreme flexibility of the joints in the arms and scoliosis. The patient presents with an aortic aneurysm and mitral valve insufficiency. The generesponsible for the development of this disease causes disorders of the connective tissue development and anomalies of the cardiovascular system. What type of gene interaction manifests in this case?
Питання 45
Name the change in the nucleotide sequence of a gene that is associated with the rotation of a certain DNA segment by 180°.
Питання 46
The parents of a newborn came for medical and genetic counseling. Their baby is suspected to have Edwards syndrome that manifests as micrognathia, microstomia, and a short upper lip. What testing methods are necessary to clarify the diagnosis?
Питання 47
Name the sequence of special functional DNA segments and structural genes that encode synthesis of a certain group of proteins that belong to one metabolic series.
Питання 48
No nitrogenous base that is a component of one DNA codon can be at the same time a component of another codon. What characteristic of the genetic code is it?
Питання 49
During meiosis, various combinations of genes form in the gametes, which ensures the appearance of new traits in the istspring. What type of variability is it?
Питання 50
During amniocentesis, fetal cells contained two sex chromatin bodies (Barr bodies). What disease can be characterized by this finding?
Питання 51
What hereditary disorders cause sickle cell anemia?
Питання 52
Aminoglycoside antibacterial drugs prevent the attachment of formylmethionyl-tRNA by binding themselves to the 30S subunit of ribosomes. What process becomes disrupted as a result?
Питання 53
What enzyme allows for synthesis of various genes from template-RNA to DNA in genetic engineering (this enzyme catalyzes the process detected in RNAviruses)?