Chapter 10 Part 1: Homework
A proto-oncogene is best defined as: a normal gene. a frameshift mutation. an inactive gene. a tumor-suppressor gene.
A) A normal gene
Normally, the tumor suppressor gene p53 induces: apoptosis. secretion of anti-growth factors. the formation of oncogenes. telomere activity.
A) Apoptosis
Sarcomas are cancers that arise from: connective tissues. glandular tissues. epithelial tissues. germ cells.
A) Connective tissues
Referring to cancer, the term anaplasia means: loss of cellular differentiation. rapid growth of cells. independence from normal cellular controls. ectopic production of hormones.
A) Loss of cellular differentiation
One way that a tumor suppressor gene can become inactivated in the absence of mutation or deletion is through gene: silencing. splicing. amplification. translocation.
A) Silencing
Organ tropism is largely determined by: the presence of specific receptors that the tumor cells can interact with. the presence of connective tissue stroma. the degree of differentiation of the tumor cells. the similarity of the organ to the original source of the tumor.
A) The presence of specific receptors that the tumor cells can interact with
Which of the following mutations would help a carcinoma in situ to become an invasive carcinoma? turning on a gene that makes a protease to digest connective tissue turning off a gene that prevents apoptosis amplifying a gene that codes for growth factor receptor overproducing a normal cellular product like mucus
A) turning on a gene that makes a protease to digest connective tissue
Which of the following is a typical characteristic of benign tumors? Cells in the tumor are undifferentiated Benign tumors are surrounded by a capsule. Benign tumors have a tendency to invade surrounding tissue. Cells in the tumor occasionally metastasize to lymph nodes.
B) Benign tumors are surrounded by a capsule
Which of the following factors is necessary for metastasis to occur? Decreased cellular motility Decreased cell adhesions Temporary cessation of cell division Proximity to body cavities
B) Decreased cell adhesions
The less differentiated a cancer cell is, the more: benign it will be. embryonic it will appear. similar it will appear to its tissue of origin. all of the above.
B) Embryonic it will appear
Cancer-causing mutations of a proto-oncogene result in: apoptosis. increased cell division. production of monoclonal antibodies. decreased cell responsiveness to growth factors.
B) Increased cell division
As a tumor grows, it exerts mechanical pressure on surrounding tissues, which results in: cellular swelling. ischemia. metastasis. extravasation.
B) Ischemia
The normal function of tumor suppressor genes in an individual without cancer is to: prevent apoptosis. limit cellular growth. stimulate cell replication. prevent cancer-causing mutations.
B) Limit cellular growth
Local tissue invasion by a tumor is accomplished by which of the following mechanisms? Release of cytokines by the tumor cells, which kills surrounding cells Release of lytic enzymes by the tumor cells, which causes tissue degradation Release of antibodies by the tumor cells, which enhances phagocytosis of surrounding tissue Release of free radicals by the tumor cells, which damages surrounding tissue
B) Release of lytic enzymes by the tumor cells, which causes tissue degradation
Mutations in which type of gene tend to be responsible for increasing the risk of cancer in cancer-prone families? oncogenes tumor suppressor genes cell cycle genes telomerase genes
B) tumor suppressor genes
Which of the following genetic events is capable, by itself, of activating an oncogene? Deletion of a proto-oncogene Loss of heterozygosity Amplification All of the above
C) Amplification
The process of triggering new blood vessel formation in a tumor is called: erythropoiesis. atherosclerosis. angiogenesis. seeding.
C) Angiogenesis
The term used to describe an aggregation of cancer cells that accumulates faster than its non-mutant neighbors is clonal: selection. stimulation. expansion. reunification.
C) Expansion
Helicobacter pylori infection is a bacterial cause of: leukemia. colon cancer. gastric cancer. bladder cancer.
C) Gastric Cancer
Which of the following cancers always arises from an initial mutation in the blood-forming cells of the bone marrow? Lymphoma Carcinoma Leukemia Sarcoma
C) Leukemia
The extension of cancer to distant tissues and organs is called: apoptosis. tropism. metastasis. malignancy.
C) Metastasis
tumor that has regional lymph node involvement but no evidence of distant metastasis to other tissues is classified as: Stage I. Stage II. Stage III. Stage IV.
C) Stage III
Immortality in cancer cells is obtained through the production of: growth factors. apoptosis signals. telomerase. tumor markers.
C) Telomerase
Which of the following is a change that might be triggered by an oncogene? permanently turning off growth signal receptors down regulate the cell cycle to decrease mitosis rate decrease production of cell-to-cell adhesion molecules decrease growth of blood vessels in the area
C) decrease production of cell-to-cell adhesion molecules
Which of the following is LEAST likely to increase one's risk of cancer? specific viral infection specific bacterial infection suppressing the inflammatory response with NSAIDS decreasing immune system function with immunosuppressant drugs
C) suppressing the inflammatory response with NSAIDS
Malignant tumors have a tendency to: grow rapidly. metastasize to distant tissues. invade surrounding tissues. all of the above.
D) All of the above
Tumor cell markers can be used to: screen individuals for cancer. diagnose tumor type. follow the clinical course of tumor development. all of the above.
D) All of the above
Tumor markers can be found in: blood. cerebrospinal fluid. urine. all of the above.
D) All of the above
Which of the following factors plays a role in the development of cancer from viral and bacterial infections? Inflammatory chemicals cause damage to DNA. Growth factors are released during the resulting inflammation. Cells divide more frequently to replace damaged tissue. All of the above factors play a role.
D) All of the above factors play a role
Cancer cells ensure adequate supply of oxygen and nutrients by releasing: autocrine growth factor lysosomal enzymes. telomerase. angiogenic factors
D) Angiogenic factors
Which of the following is NOT a typical characteristic of cancer cells? Loss of cellular self-destruct mechanisms Unlimited replication Autocrine stimulation Decreased responsiveness to growth signals
D) Decreased responsiveness to growth signals
Which of the following mutational routes is necessary to cause cancer with a tumor suppressor gene mutation? Point deletion on one chromosome Chromosomal translocation Gene amplification Deletion of both copies of a tumor suppressor gene
D) Deletion of both copies of a tumor suppressor gene
Select the TRUE statement: Loss of heterozygosity is necessary for oncogene activation. Tumor suppressor genes are often mutated through gene amplification. A single genetic mutation can turn a normal cell into a metastatic cancer cell. Epigenetic silencing is a reversible process
D) Epigenetic silencing is a reversible process
Which of the following viruses has been implicated in the development of cervical cancer? Herpes virus HIV Epstein-Barr virus Human papilloma virus
D) Human Papilloma Virus
Chronic active hepatitis B infection is a risk factor for developing which of the following types of cancer? Lung Leukemia Pancreas Liver
D) Liver