The major hazard of a rubella infection affecting a young woman is:
congenital malformations in the fetus if a susceptible pregnant woman acquires the infection in the first trimester.
Which of the following statements regarding Down syndrome is INCORRECT?
Cells from an affected child reveal an extra sex chromatin body (Barr body) attached to the nuclear membrane of the cells.
What is the main application of amniocentesis?
Prenatal detection of chromosome abnormalities in a fetus carried by a woman over age 35
Which of the following is most likely to lead to congenital malformation or developmental disturbances in the developing fetus?
Heavy alcohol consumption during pregnancy
A mother has given birth to an infant with cytomegalic inclusion disease; what does this indicate?
The mother has been previously infected with the cytomegalovirus (CMV), and the infection became activated during the pregnancy, or the mother acquired a CMV infection during her pregnancy.
What usually causes Down syndrome?
Fertilization of an ovum containing an abnormal number of chromosomes
Which of the following statements about the fragile X syndrome is INCORRECT?
There is no relationship between the number of triplet repeats and the severity of the mental deficiency.
Which of the following conditions is NOT an indication for amniocentesis?
Maternal age younger than 35 years
All of the following statements about chromosomal mosaicism are correct EXCEPT:
Mosaicism results from chromosome nondisjunction occurring in the ovum before fertilization.
Chromosome deletion occurs when:
a chromosome breaks during meiosis and the broken piece is lost from the cell.
A misplaced chromosome or part of a chromosome attached to another chromosome is called a __________.
Reciprocal translocation occurs when:
a chromosome breaks during meiosis and the broken piece is lost from the cell.
A common abnormality in females, __________ syndrome results from an absence of one X chromosome.
__________ is caused by a deficiency of protein called antihemophilic globulin, which is required for normal blood coagulation.
__________ is characterized by excessive absorption of iron, which accumulates within the body and disrupts organ functions.
A pregnant woman with phenylketonuria does not need to adhere to a phenylalanine-restricted diet because the high concentration of phenylalanine in the woman's blood does not harm the fetus.
An increased concentration of alpha fetoprotein in maternal blood or amnionic fluid suggests that the fetus has Down syndrome.
Most infants with Down syndrome are born to mothers who are carriers of a chromosome 21, which is attached to another chromosome (translocation carrier).
A neural tube defect (anencephaly or spina bifida) can usually be identified in an affected fetus by mean of an ultrasound examination performed at about 16 weeks gestation.
The sex chromatin body (Barr body) represents an inactivated X chromosome and is only encountered in persons having two X chromosomes and lacking a Y chromosome.
Consumption of alcoholic beverages in pregnancy does not harm the fetus if the amount of alcohol consumed does not exceed 1 pint of liquor per day.
Nondisjunction occurs when homologous chromosomes in germ cells separate from one another in either the first or the second meiotic division.
The most common autosomal trisomy seen in newborn infants is that of chromosome 13, which causes Down syndrome.
A malignant tumor arising from glands within the lining of the uterus is a/an __________.
Which of the following statements is INCORRECT?
The genome of the cells of many tumors is unstable, and the tumor cells may undergo additional mutations; however, such mutations do not affect the growth rate or other biologic properties of the tumor.
How does our immune system protect us from cancer?
It recognizes and destroys abnormal cells, which differ from normal cells.
Which of the following statements is correct?
Adjuvant chemotherapy attempts to destroy subclinical micrometastases that have already spread from the primary tumor.
A 25-year-old woman has an abnormal pap smear. What does this mean?
The genital tract is shedding abnormal cells and requires further investigation.
Which of the following statements regarding a dermoid cyst (benign cystic teratoma) of the ovary is INCORRECT?
Sometimes metastasizes to lungs and brain
Which of the following is a malignant tumor arising from pigment-producing cells of the skin?
Which of the following statements about tumors is true?
Tumors are the product of a mutation in a normal cell that causes that cell to grow and reproduce itself abnormally.
Choose the word or phrase below that best completes the following statement: Malignant tumor cells do not wear out and die as normal cells do, but instead they __________.
become immortal and proliferate indefinitely
Choose the answer below that best describes the difference between a carcinoma and a sarcoma.
A carcinoma arises from surface, glandular, or parenchymal epithelial tissues; a sarcoma arises from other primary tissues.
Which of the following is true?
Some lymphomas may start out indolent and transform suddenly into a more aggressive tumor.
Conditions such as leukoplakia or lentigo maligna should be regarded as:
an indication that changes have occurred in tissue that could become cancerous if the site is left untreated.
Multiple myeloma differs from leukemia in the following EXCEPT:
Large number of neoplastic cells typically spill into the peripheral blood.
Blood tests to detect most tumor-associated antigens such as carcinoembryonic antigen (CEA) are used primarily as screening tests to detect malignant tumors in asymptomatic patients while the tumors are still small and easily curable by surgical treatment.
Classification of a lymphoma is based in part on its histologic structure and growth pattern, which provides prognostic information and serves as a guide to treatment.
In acute leukemia, the leukemic cells are mostly primitive cells, whereas in chronic leukemia, the leukemic cells are mostly mature cells.
Some chemotherapy drugs impede tumor cell growth by blocking growth factor receptors on the tumor cells so that the tumor cells are unable to respond to the growth factors that stimulate cells to divide.
Philadelphia chromosome-positive chronic granulocytic leukemia can often be treated effectively by a drug that inhibits the hyperactive tyrosine kinase produced by the abnormal gene (bcr/abl) responsible for the granulocyte proliferation.
Cancer is generally the result of a collection of genetic mutations or changes, not simply a mutation in one gene.
Graft versus host reaction represents a response of transplanted cells against the patient receiving the transplant.
papilloma virus infection
oral cavity squamous cell carcinoma
Examination of tissue under a microscope to identify the presence and type of cancerous cells
The process by which malignant cells travel from their site of origin to establish tumors elsewhere in the body
A 5-year-old male child has a bleeding disease that is characterized by areas of hemorrhage in the joints and muscles after minor injuries. Laboratory tests reveal a deficiency of a coagulation factor active in the early phase of blood coagulation (formation of intrinsic thromboplastin). What is the most likely diagnosis?
Which of the following statements regarding disseminated intravascular coagulation syndrome is NOT true?
It is a frequent complication of pulmonary embolism.
are small pinpoint areas of bleeding in the skin and deeper tissues resulting from leakage of blood through minute defects in the capillary endothelium.
Blood plasma contains several different proteins, called __________, which, when activated, interact to produce a blood clot.
In phase 2 of the blood coagulation process, __________ is converted into __________.
In phase 3 of the blood coagulation process, __________ is converted into __________.
Deficiencies of plasma coagulation factors often lead to large areas of hemorrhage called __________.
time measures the time it takes for blood plasma to clot after adding a lipid substance and calcium to start the clotting process.
time measures the time it takes for blood plasma to clot after adding a preparation of thromboplastin with calcium to start the coagulation.
test bypasses the first two phases of blood coagulation and primarily measures the level of fibrinogen.
Which of the following statements about von Willebrand disease is NOT true?
It is characterized by episodes of hemorrhage in joints and internal organs after minor injury.
Many blood coagulation factors are produced in the liver, and their concentrations in the blood are reduced in patients with liver disease.
Thromboplastic material liberated from a dead fetus retained with the uterus may induce a hemorrhage state (disseminated intravascular coagulation syndrome) in the mother.
Normally, small blood vessels expand after injury, helping to seal the defect by a blood clot.
Partial thromboplastin time measures the time it takes for blood plasma to clot after adding a lipid substance and calcium.
The constriction of small blood vessels following injury serves as the first line of defense against bleeding.