Quiz

QUIZ

1. What protein toughens the outer layer of the skin so it can be a barrier against infection?

a. Elastin b. Keratin c. Collagen d. Actin

Answer: b. Keratin is part of the epidermis. It leads to toughening of the skin so that it can better resist the passage of pathogens through the tissues. It helps provide a mechanical barrier for the skin.

2. What component of mucous membranes least likely prevents disease?

a. Movement of cilia b. Antibacterial proteins c. Mucus d. Phagocytosis

Answer: d. Each of these is important in helping mucous membranes fight disease except for phagocytosis, which is not a function of the mucous membranes.

3. What part of the GI tract contains hydrochloric acid to protect the system against pathogens?

a. Esophagus b. Mouth c. Stomach d. Small intestine

Answer: c. There are specialized cells in the stomach that make hydrochloric acid that is protective against pathogenic bacteria.

4. Lysozyme is an important antibacterial substance. What does it do?

a. It binds iron so it cannot be used by bacteria. b. It breaks down the bacterial peptidoglycan layer. c. It forms pores in the bacterial cell membrane. d. It blocks DNA synthesis in bacterial organisms.

Answer: b. Lysozyme breaks down the peptidoglycan layer of the cell wall, mainly affecting gram-positive bacteria.

5. What is the membrane attack complex made of?

a. Antibodies b. Complement proteins c. Cell wall fragments d. Enzymes

Answer; b. The membrane attack complex or MAC is made from complement proteins that aggregate to kill bacteria.

6. What do mast cells produce in the innate immune system?

a. Heparin and histamine b. Complement proteins c. Antibodies d. Chemoattractants

Answer: a. Mast cells make heparin and histamine, which aid in the inflammatory response.

7. Which cells are most important in the allergic response and in killing off helminths and protozoans?

a. Mast cells b. Basophils c. Eosinophils d. Neutrophils

Answer: c. The eosinophil count will go up in allergies and when there is an infection with helminths or protozoans because these cells are important in these types of responses.

8. Which cells do not participate in phagocytosis?

a. Neutrophils b. Dendritic cells c. Macrophages d. NK cells

Answer: d. Each of these cells participate in phagocytosis, except for NK cells or natural killer cells.

9. What do pattern recognition receptors on phagocytes recognize?

a. Bacterial antibodies b. Cytokines c. Pyrogens d. Pathogen-associated molecular patterns

Answer: d. These pattern recognition receptors are designed to recognize PAMPs or pathogen-associated molecular patterns, which identify a certain organism as being pathogenic.

10. What happens to the pathogen after it is bound to a phagocyte?

a. The pathogen is taken inside and digested. b. A compound is secreted that surrounds and deactivates the pathogen. c. Proteases exit the phagocyte to kill the pathogen. d. Antibodies are made that congeal pathogens together.

Answer: a. After binding to the phagocyte, the pathogen is taken inside and digested inside a phagolysosome.