Question 1

Which of the following conditions is characterized by a defect of a DNA repair enzyme?&#10;A) Neurofibromatosis&#10;B) Hereditary polyposis coli&#10;C) Xeroderma pigmentosum&#10;D) Wilms' tumor&#10;E) Hodgkin's lymphoma

Accepted Answer

Xeroderma pigmentosum is characterized by a defect in DNA repair enzymes, specifically those involved in the repair of UV-induced DNA damage. Neurofibromatosis, hereditary polyposis coli, Wilms' tumor, and Hodgkin's lymphoma are not caused by defects in DNA repair enzymes.

Question 2

Teratomas originate from:&#10;A) Germ cells of the ovary&#10;B) Brain cells&#10;C) Thyroid cells&#10;D) Endocrine cells of the pancreas&#10;E) Fallopian tubes

Accepted Answer

Teratomas originate from germ cells, which are located in the ovaries and testes. They are not associated with brain cells, thyroid cells, endocrine cells of the pancreas, or fallopian tubes.

Question 3

The cancer of chimney sweeps identified in the eighteenth century in England was related to a component of tar that is chemically classified as:&#10;A) Polycyclic hydrocarbons&#10;B) Aflatoxin B&#8321;&#10;C) Azo-dyes&#10;D) Naphthylamine&#10;E) Arsenic

Accepted Answer

The cancer of chimney sweeps in eighteenth-century England was caused by exposure to soot and tar, which contained polycyclic hydrocarbons.

Question 4

Hodgkin's lymphoma is a neoplasm that typically involves the:&#10;A) Brain&#10;B) Lungs&#10;C) Heart&#10;D) Liver&#10;E) Lymph nodes

Accepted Answer

Hodgkin's lymphoma is a cancer of the lymphatic system, specifically the lymph nodes. It can also involve other parts of the body such as the spleen, liver, bone marrow, and lungs, but lymph nodes are typically the primary site of involvement.

Question 5

The incidence of which cancer has been rising in the United States during the past 20 years?&#10;A) Carcinoma of the lung&#10;B) Carcinoma of the liver&#10;C) Carcinoma of the stomach&#10;D) Carcinoma of the thyroid&#10;E) Malignant brain tumors

Accepted Answer

The incidence of carcinoma of the lung has been rising in the United States during the past 20 years, largely due to increased rates of smoking and exposure to environmental toxins.

Question 6

Alpha-fetoprotein is a tumor marker for malignant tumors originating in the:&#10;A) Brain&#10;B) Lung&#10;C) Liver&#10;D) Uterus&#10;E) Thyroid

Accepted Answer

Alpha-fetoprotein is a tumor marker for liver cancer. It is not typically elevated in brain, lung, uterus, or thyroid cancers.

Question 7

Which of the following physical carcinogens is the cause of most skin cancers in humans?&#10;A) Ultraviolet light&#10;B) Infrared light&#10;C) X-rays&#10;D) Radon&#10;E) Gamma rays

Accepted Answer

Ultraviolet light is the most common physical carcinogen that causes skin cancers in humans. Exposure to UV radiation from the sun is a major risk factor for skin cancer, including basal cell carcinoma and squamous cell carcinoma.

Question 8

Carcinoma of the stomach has the highest incidence in:&#10;A) England&#10;B) Japan&#10;C) United States&#10;D) Israel&#10;E) France

Accepted Answer

Japan has the highest incidence of carcinoma of the stomach, with rates more than double those in the United States and five times those in the United Kingdom and France. This is believed to be due to dietary factors, including high salt intake and low consumption of fresh fruits and vegetables.

Question 9

The most important source of chemical carcinogens in the human habitat is:&#10;A) Cigarette smoke&#10;B) Asbestos&#10;C) Air pollution&#10;D) Food additives&#10;E) Pesticides in the food

Accepted Answer

Cigarette smoke is the largest source of chemical carcinogens in the human habitat. It contains over 70 known carcinogens, including polycyclic aromatic hydrocarbons (PAHs) and nitrosamines, which are linked to lung cancer, bladder cancer, and many other types of cancer.

Question 10

Retinoblastoma gene (Rb-1)is classified as a(n):&#10;A) Oncogene&#10;B) Tumor suppressor gene&#10;C) Point mutation&#10;D) Gene amplification&#10;E) Viral oncogene inserted into the human genome

Accepted Answer

The Retinoblastoma gene (Rb-1) is a tumor suppressor gene, which means that its normal function is to prevent the development of cancer by regulating cell growth and division. Mutations or deletions in the Rb-1 gene can lead to the loss of its tumor suppressor activity and contribute to the development of retinoblastoma, a rare eye cancer that typically affects young children. Therefore, the best choice is B, tumor suppressor gene.

Question 11

Many tumors secrete their own growth factors.This form of stimulation is called:&#10;A) Autocrine&#10;B) Heterocrine&#10;C) Paracrine&#10;D) Endocrine&#10;E) Exocrine

Accepted Answer

The answer of Many tumors secrete their own growth factors.This...

Question 12

Workers employed in the chemical industry and exposed to high levels of aniline dyes are at increased risk of developing cancer of the:&#10;A) Brain&#10;B) Lung&#10;C) Stomach&#10;D) Urinary bladder&#10;E) Testis

Accepted Answer

The answer of Workers employed in the chemical industry and...

Question 13

A lung tumor that has spread to the brain has metastasized via:&#10;A) Lymphatics&#10;B) Nerves&#10;C) Blood vessels&#10;D) Cerebrospinal fluid&#10;E) Pleural fluid

Accepted Answer

The answer of A lung tumor that has spread to...

Question 14

Human papillomavirus (HPV)has been implicated in the pathogenesis of carcinoma of the:&#10;A) Lips&#10;B) Cervix of the uterus&#10;C) Liver&#10;D) Ovaries&#10;E) Pancreas

Accepted Answer

The answer of Human papillomavirus (HPV)has been implicated in the...

Deck 4: Neoplasia