WGU D115 UNIT 2 exam questions and answers

Which type of genetic disease affects males more frequently than females? Sex-linked recessive Autosomal recessive Autosomal dominant Sex-linked dominant Sex-Linked recessive. Since males only have one X and one Y, if the affected chromosome has the illness, it will be expressed. In which two conditions are chromosomal abnormalities the leading known cause? Intellectual disability Respiratory disorders Fetal miscarriage Cardiovascular disease Mental illness Check My Answer Intellectual disability and fetal miscarriage. Chromosome abnormalities are the leading known cause of intellectual disability and fetal miscarriage. What are three examples of prenatal diagnostic studies? Drug-sensitivity testing Chorionic villus sampling (CVS) Microscopy of cervical mucosa Preimplantation genetic testing (PGT) Amniocentesis Chorionic villus sampling (CVS), amniocentesis, and preimplantation genetic testing (PGT) are examples of prenatal diagnostic studies and are performed in vitro. CVS is a form of genetic testing that provides genetic information found in utero and is usually performed between weeks 11 and 14 of pregnancy. An amniocentesis is a form of genetic testing that evaluates amniotic fluid and is usually performed during the second trimester, between weeks 15 and 20 of pregnancy. PGT is performed on the embryo prior to implantation. Which genetic disorder is characterized by the presence of a zygote having one chromosome with a normal complement of genes and one chromosome with a missing gene? Klinefelter syndrome Down syndrome Cri du chat syndrome Turner syndrome Cri du chat syndrome (translated as "cry of the cat") is caused by a DNA deletion. This term describes the cry often heard from a baby affected by the syndrome. Cri du chat syndrome can present as a microcephalic, low birth-weight baby with a piercing cry. How can an X-linked recessive disease skip generations? Mothers cannot pass X-linked genes to their sons. Females are hemizygous for the X chromosome. The disease can be transmitted through female carriers. These diseases need only one copy of the gene in females. The disease can be transmitted through female carriers. Since females have two copies of the X chromosome, the mother may provide an unaffected X to a daughter or son. Furthermore, a daughter may not show signs of the disease because she has the other X (the only X the father can give to a female) to cancel it out. Which type of risk is referred to as the ratio of the disease rate among the entire population to the disease rate in an unexposed population? Relative Attributable Contingency Causal Relative risk is a ratio of probability, not an actual occurrence of disease. What are the empirical risks for most multifactorial diseases based on? Direct observation Chromosomal testing Relative risks Liability thresholds Many factors from lifestyle to genetics affect multifactorial diseases. Observation and evaluation of each case individually provides the most thorough and accurate assessment. What refers to the silenced gene of a gene pair. Imprinted, activated, mutated, altered The imprinted gene is the silent gene of a gene pair. What is the primary reason that some older adults have impaired inflammation and wound healing? The circulatory system cannot adequately perfuse tissues. The underlying chronic illness exists. The complement is deficient. The number of mast cells is insufficient. The underlying chronic illness exists. A generalized inflammatory response seen in chronic illness depletes the body's reserves to fight against illness. Which cells are the body's primary defense against parasite invasion? B lymphocytes Eosinophils Neutrophils T lymphocytes Eosinophils are the body's primary defense against parasites. What Phagocytes bacteria? eosinophils macrophages perforin Macrophages work by eating or phagocytosing bacteria. What is the first response to a foreign pathogen? cytotoxic T helper T cells phagocytic Helper T cells Which characteristic is the most important determinant of immunogenicity when considering the antigen? Foreignness Quantity Size Complexity Immunogenicity is primarily based on the ability to recognize something foreign. How are erythrocytes destroyed when mismatched blood is administered, causing an ABO incompatibility? Phagocytosis by macrophages Complement-mediated cell lysis Phagocytosis in the spleen Natural killer cells The complement pathway is activated in response to blood incompatibility. What is the hypersensitivity reaction that causes atopic dermatitis? An immediate (type I) hypersensitivity reaction causes atopic dermatitis. Which four infections are considered fungal infections? Ringworm Candida Cholera Athlete's foot Aspergillus Check My Answer Infection with a fungus is called mycosis and includes dermatophytes (e.g., tineas, which refers to several skin mycoses, including ringworm and athlete's foot) and yeasts, which include candida and aspergillus. When is the earliest after sexual transmission of HIV that lab results can detect infection? 1 to 2 days 2 to 4 months 4 to 8 weeks 4 to 10 days Lab testing can detect HIV RNA 4 to 10 days after sexual transmission, whereas HIV antibody testing may take 23 to 90 days to result in a positive test. Repeat testing may be needed to rule out a false negative test due to testing too soon after exposure, especially if a high likelihood of exposure is suspected. What is a characteristic of exotoxins? Able to initiate the complement and coagulation cascades Released during bacterial growth Contained in cell walls of gram-negative bacteria Released during the lysis of bacteria Exotoxins are released during bacterial growth. Which dietary lifestyle choice has been associated with a decreased risk for developing colon cancer? Increased consumption of dairy products Decreased consumption of high-fat foods Decreased consumption of artificial food coloring Increased consumption of foods containing vitamin C The results of decreased fat consumption have been widely studied and have demonstrated a decreased risk of developing colon cancer. Which cancer is an individual who has worked with asbestos for over 40 years most likely to develop? Stomach Leukemia Bladder Lung Asbestos exposure results in an increased risk of lung and lung lining cancer. Which statement is true regarding ultraviolet (UV) light? The degree of damage is not affected by the light's wavelength. It causes basal cell carcinoma and squamous cell carcinoma. The principal source of ultraviolet radiation (UVR) is tanning beds. It can cause the formation of sarcomas. UV light causes basal cell carcinoma and squamous cell carcinoma when the UVB rays hit DNA strands, causing thymine base pairs that are side by side to pair together, becoming thymine dimers. These thymine dimers lead to cell death or cancer.