LIVING WITH THE EARTH
MULTIPLE CHOICE
1. How many synthetic chemicals are currently in commercial use in the United States, and whose toxicity is not widely known or understood?
2. _______________is the most likely process of absorption for amino acids.
3. Which of the following sites in the respiratory system is the most likely place for the carbon dioxide and ozygen to exhange in the blood?
4. Which of the following processes, when prolonged and severe, can be life threatening such as in asthmatic attacks?
5. What is the best estimate for the area of skin coverage in the average adult?
6. By what absorptive process does hexane pass through the skin?
How long is the average adult human gastrointestinal tract?.
8. Where is the most likely site for the absorption of toxic agents in the gastrointestinal tract?
9. What is the mechanism for the harmful effects of CO (carbon monoxide)?
10. What is the major organ responsible for detoxification in the body?
11. What is the major toxic mechanism for hydrogen cyanide?
12. What is the major mechanism for toxicity of dithiocarbamate during alcohol consumption?
13. Which of the following substances can cause a syndrome in infants referred to as "blue baby"?
14. Which of the following refers to a substance that is attached to an antigen and promotes an antigenic response.
15. Which kind of cells are the primary targets of the AIDS virus?
16. The largest percent of antibodies belong to the _________ class.
17. Which of the following hypersensitivity reactions is most often seen in transfusion reactions?
18. What kind of hypersensitivity is associated with asthma?
19. What kind of the following interactions is characterisitc of that for caffeine and sleeping pills?
19. Yu-cheng Disease in Taiwan is due to the toxic effect of _________ .
20. When were both federal regulatory and legislative efforts begun to reduce lead hazards, including the limitation of lead in paint and gasoline?
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TRUE AND FALSE
1. Lead has been recognized as a hazard since early civilization when it was used to store wine, to pipe water, and even as vessels in which to cook food.
T_______ F _______ True:- pg. 5-2
2. Once a potential toxic substance goes into our society, it automatically produces an adverse effect.
T_______ F _______ False - pg. 5-3
3. External respiration refers to the exchange of gases between blood and individual cells.
T_______ F _______ False - pg. 5-8
4. Sulfur oxides tend to reach deep into lung tissue while nitrogen dioxides tend to act in the upper moist airways of the respiratory tree.
T_______ F _______ False - pg. 5-8
5. The skin is the body's largest organ and consistis of many interconnected tissues.
T_______ F _______ True - pg. 5-8
6. Epidermis is the outer, thinner layer of the skin and dermis is the inner and much thicker layer of the skin.
T_______ F _______ True - pg. 5-9
7. The gastrointestinal tract is a major route of absorption for many toxic agents including mercury, lead, and cadmium.
T_______ F _______ True - pg. 5-11
8. A toxin can produce a harmful effect upon an organ only by stimulating the normal metabolic actions of that particular organ.
T_______ F _______ False - pg. 5-12
9. Many enzymes require a nonprotein component called apoenzyme and a protein component called cofactor to become active.
T_______ F _______ False - pg. 5-12
10. Cadmium and beryllium are believed to inactivate enzymes by blocking the sites on the enzyme where such co-factors as iron normally attach.
T_______ F _______ False - pg. 5-13
11. When lead covalently bonds to an enzyme, its inhibition of enzymes is considered to be irreversible.
T_______ F _______ True - pg. 5-13
12. The exposure of allergens can trigger a diminished immune response in some people.
T_______ F _______False - pg. 5-15
13. Chemical pollutants such as ozone can depress the immune response by inactivating alveolar macrophages.
T_______ F _______ True - pg. 5-15
14. B cells are the principle agents in cell-mediated immunity.
T_______ F _______ False - pg. 5-15
15. Humoral immune responses are characterized by subcutaneous bleeding.
T_______ F _______ True - pg. 5-16
16. The environmental pollutants such as ozone and fine particulates contribute to the significant rise in the numbers and severity of asthma cases.
T_______ F _______ True - pg. 5-22
17. If absorbed, lead tends to be stored mostly in fatty tissue.
T_______ F _______ False- pg. 5-26
18. Dioxin is considered to be one of the most toxic natural chemicals.
T_______ F _______ False - pg. 5-33
19. The EPA has listed 20ug/dl as the maximum acceptable blood lead level for fetuses and young children.
T_______ F _______ False - pg. 5-40
20. Lead may impair fertility in both men and women when blood lead levels approach 50 ug/dl.
T_______ F _______ True - pg. 5-41
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SHORT ANSWER / ESSAY QUESTIONS
1. What are the possible toxic mechanisms for chemicals?
2. List the variety of processes of absorption including their characteristics.
(1) Diffusion: molecules move from areas of high concentration to low concentration;
(2) Facilitated Diffusion: require specialized carrier proteins, no high energy phosphate bonds are required;
(3) Active Transport: ATP is required in conjunction with special carrier proteins to move molecules through a membrane against a concentration gradient;
(4) Endocytosis: particles and large molecules that might otherwise be restricted from crossing a plasma membrane can be brought in or removed by this process. (- pg. 5-5)
3. How do toxic substances enter the body?
There are several ways in which toxic substances can enter the body. They may enter through the lungs by inhalation, through the skin, mucous membranes or eyes by absorption, or through the gastrointestinal tract by ingestion. (- pg. 5-5)
4. What are the major functions of the skin?
The skin can help to :
5. What are the three major mechanisms for the harmful effects of environmental toxins?
6. List the four major types of hypersensitivity reactions: