Unformatted text preview: Biology 181, Sections 1, 2H, 3, 4H Drs. Richard Hallick and William Grimes Exam 4; Dec. 2, 2005 VERSION ONE
1) What is the correct order of activation for an adaptive immune response? a) dendritic cells, B cells, helper T cells b) B cells, dendritic cells, helper T cells c) helper T cells, dendritic cells, B cells d) dendritic cells, helper T cells, B cells e) B cells, helper T cells, dendritic cells 2) What part of the antibody is coded for by DNA sequences that have been rearranged during B cell development in our bone marrow and determines the specificity for antigen? a) heavy constant region, light constant region b) heavy variable region, light constant region c) heavy variable region, light variable region d) heavy constant region, light variable region e) all of the above 3) Which of the following is not a part of the innate immune system? a) skin b) secretion of fluids containing lysozyme c) macrophages d) mucus membrane secretions e) T cells 4) Cytotoxic T cells: a) produce antibody against cell free pathogens b) require B cells for regulated activation c) protect against pathogens that have invaded our cells d) regulate the innate immune response e) cause cancer in humans 5) Multiple genetic loci code for the histocompatibility antigens (MHC) of humans. The loci are called HLA- A, B, and C, with each having multiple alleles. We inherit A, B, and C alleles from each of our parents. The function of the MHC proteins is to present fragments of pathogens to our immune system. Individuals of which of the following genotypes are most likely to survive attack by a new pathogen? a) homozygous for A, B, and C b) homozygous for A and B, and heterozygous for C c) homozygous for A, and heterozygous for B and C d) heterozygous for A and homozygous for B and C e) heterozygous for A, B, and C 6) According to the clonal selection theory: a) an antibody changes its shape in response to antigen b) animals contains only one type of B cell c) animals make many kinds of B cells, each producing only one kind of antibody d) each B cells produces many kinds of antibodies e) many clones of anti-self lymphocytes appear in the bloodstream 7) How does the immune system have the ability to make both a faster and stronger response upon a second or third exposure to pathogens that are free in our bloodstream? a) dendritic cells are converted to memory cells b) memory B cells and memory helper T cells are produced during a first exposure to antigen c) macrophages that engulf antigen are converted to memory cells d) cytotoxic T cells proliferate, and cause a more rapid B cell response during a secondary infection e) antibody produced during the first infection is stored and can be re-released if the pathogen is encountered a second time 8) Which of the following statements does NOT describe a function of dendritic cells of the innate immune system? a) attracted by chemokines to sites where cells are damaged or pathogens are present b) phagocytose (eat) pathogens through receptors specific for molecules common to bacteria and viruses c) process pathogen into fragments which are displayed on cell surfaces in complexes with MHC proteins d) migrate to lymph nodes where activation information is signaled to appropriate T cells e) stimulate B cells to rearrange DNA to develop antibody capable of binding to antigen fragments 9) Statins (Lipitor, Zocor, Mevacor, Pravachol, Crestor) are the number one selling drug in our country. Currently, 11 million people are taking a statin drug. The national lipid guidelines estimate that 36 million people should actually be taking statins. How do statins reduce the risk of cardiovascular disease? a) block production of cholesterol by inhibiting HMG CoA reductase b) reduced cholesterol causes cells to increase production of LDL receptors c) block immune cells signaling reducing inflammatory responses d) "a" and "b" e) "a", "b", and "c" 10) In the biosynthesis of the LDL receptor, the signal sequence is: a) the signal for the cell to start transcription of the mRNA for the LDL receptor b) an amino acid sequence produced during mRNA translation that directs the mRNA-ribosome complex to bind to the rough endoplasmic reticulum c) an RNA sequence that codes for the LDL receptor and binds to the surface of the rough endoplasmic reticulum d) the part of the LDL receptor that binds to LDL particles, signaling the start of endocytosis into the cell e) the part of the LDL receptor that causes localization in "coated pits" on the cell surface 11) The disease familial hypercholesterolemia may be caused by: a) inability of the LDL receptor to move from the endoplasmic reticulum (ER) to the Golgi apparatus and cell surface b) loss of the gene coding for the LDL receptor c) failure of the LDL receptor to be recycled d) loss of binding of LDL particles by the receptor e) all of the above 12) What is common to the many risk factors (smoking, old age, diabetes, hypertension) that increase our chance of developing heart disease? a) promote higher HDL levels b) lower LDL levels c) increase cholesterol biosynthesis d) increase triglyceride biosynthesis e) increase oxidation of phospholipids on LDL particles 13) The development and progression of cancer is caused when: a) a proto-oncogene is converted to an oncogene b) a tumor suppressor gene is deleted from the chromosome c) cell signaling pathways in the cell are activated by mutation d) a tumor causes angiogenesis or growth of new blood vessels e) a series of changes occur in oncogenes, tumor suppressor genes, and signaling pathways 14) Mutations in genes that lead to chromosome instability, convert proto-oncogenes to oncogenes, and cause loss of tumor suppressor genes can be described respectively as: a) stuck accelerator, brake failure, inept mechanic b) brake failure, inept mechanic, stuck accelerator c) brake failure, stuck accelerator, inept mechanic d) stuck accelerator, inept mechanic, brake failure e) inept mechanic, stuck accelerator, brake failure 15) The accumulation of new mutations during the progressive growth of a tumor may lead to all of the following except: 16) 17) 18) 19) 20) 21) 22) a) the formation of new tumor suppressor genes b) the conversion of proto-oncogenes to oncogenes c) the loss of tumor suppressor genes d) the mutation of stability genes e) the growth of new blood vessels in the tumor Which of the following describe consequences of the conversion of a proto-oncogene to an oncogene? a) the production of excess or abnormal growth factors b) altered receptors stimulating cell growth in the absence of ligand c) hyperactive kinases d) abnormally or inappropriately activated transcription factors e) all of the above If your diet includes 150 calories (about one coke) above your daily need three times each week, how much fat would you expect to gain in one year? a) less than 1 pound b) less than 3 pounds c) between 5 and 7 pounds d) between 8 and 10 pounds e) over 12 pounds Lack of exercise and excess caloric intake leads to a resistance to signaling by leptin and insulin. What are the metabolic consequences? a) decreased eating and increased energy expenditure b) reduction in fat synthesis and storage c) increased eating and decreased energy expenditure d) excess metabolism of glucose and fats e) decreased metabolism of glucose and fats What is the function of the proteins encoded by the bicoid and nanos genes of the fruit fly, Drosophila melanogaster? a) DNA binding b) transcriptional activation c) protein kinase d) Both a and b e) a, b, and c At what event during frog development is the overall body plan established, i.e. when are the location of the dorsal-ventral, anterior-posterior, and right-left axes first determined? a) entry of the sperm into the egg b) first cleavage c) blastula d) gastrula e) neurulation What happens during gastrulation in frogs? a) development of three embryonic germ layers b) massive cell migration into the interior of the embryo c) significant increase in size of the embryo d) both a and b e) a, b, and c During development of the Drosophila melanogaster (fruit fly) larva, different classes of regulatory genes are required to establish asymmetry in the egg and the embryo. What class of genes: (1) are the earliest to act in establishing the body plan; (2) diffuse from the anterior and posterior poles of the embryo forming concentration gradients; and (3) are necessary to determine the head and tail ends of the embryo? a) Antennapedia b) gap c) pair-rule d) segment polarity e) maternal effect 23) Which embryonic germ layer has as one of its fates to become brain and nervous system: a) mesoderm b) archenteron c) endoderm d) blastocoel e) ectoderm 24) What amphibian embryonic tissue was shown by Spemann and Mangold to induce the formation of the neural plate, and in some cases, to induce a complete second embryo. a) equatorial mesoderm b) dorsal lip of the blastopore c) yellow crescent d) optic cup e) zone of polarizing activity 25) Which of the following is NOT a characteristic activity of homeotic genes or their gene products? a) Determine the direction of developmental fates of groups of cells in a segment of the embryo. b) Include a DNA sequence called the homeobox that is similar in all homeotic genes. c) Are altered in homeotic mutations such as Antennapedia, causing abnormal development of the head. d) Are similar between mice and flies for both structure and order on the chromosome. e) Cause the egg fertilization membrane to rise upon sperm entry, preventing polyspermy 26) The process by which a cell or group of cells in an embryo becomes fixed into a predictable developmental pathway is known as: a) development b) differentiation c) morphogenesis d) determination e) neurulation 27) Where does fertilization of a human egg normally occur? a) oviduct b) uterus c) vagina d) ovary e) follicle 28) What female sex hormone is inhibited during most of the ovarian cycle by estrogen, but is stimulated by estrogen to peak concentrations on days 12-14 and is most responsible for triggering rupture of the ovarian follicle and ovulation? a) gonadotropin releasing hormone b) follicle stimulating hormone c) luteinizing hormone d) progesterone e) human chorionic gonadotropin 29) Which human female hormone is produced in the ovaries primarily during the 10-day period following ovulation, and serves as an important signal to the uterus to maintain the endometrial lining? a) testosterone b) estrogen c) follicle-stimulating hormone d) progesterone e) gonadotropin 30) One of the major differences between the sexual responses of human males and females is: a) the increase in blood pressure in males b) the increase in heart rate in females c) the presence of a refractory period in females d) the presence of a refractory period in males after orgasm e) the increase in muscle tension in males 31) In both males and females, release of ______________ by the hypothalamus in turn stimulates cells of the anterior pituitary to increase their secretion of _______________ and ______________ . a) luteinizing hormone (LH); follicle-stimulating hormone (FSH), gonadotropin-releasing hormone (GnRH) b) gonadotropin-releasing hormone (GnRH); luteinizing hormone (LH), follicle-stimulating hormone (FSH) c) follicle-stimulating hormone (FSH); gonadotropin-releasing hormone (GnRH) luteinizing hormone (LH) d) gonadotropin-releasing hormone (GnRH); luteinizing hormone (LH), leptin e) follicle-stimulating hormone (FSH); estrogen, testosterone 32) Which of the following birth control methods offers the best protection against sexually transmitted diseases? a) norplant hormonal implants b) emergency contraception c) birth control pills d) surgical sterilization e) none of these offer STD protection 33) Which sexually transmitted disease can be treated and cured with antibiotics? a) Hepatitis B b) AIDS c) Genital warts d) Genital herpes e) Chlamydia ...
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