Bio Chapter 9 HW

Any substance that produces an inappropriate response of the immune system is referred to as a(an)

allergen

Microorganisms that cause death and disease are called __________

pathogens

The pain associated with the inflammatory response is the direct result of ________.

the SWELLING of the tissue and the chemicals released from certain cells

Which one of the following best explains why people get so many colds in their lifetime?

The viruses that cause colds EVOLVE RAPIDLY, which results in a change in their antigenic structure.

What is the role of mast cells in the inflammatory response?

They release chemicals that DILATE blood vessels at the wound site.

Which of the following statements about viruses is true?

Viruses require a host cell in which to reproduce.

A life-threatening allergic reaction (difficulty in breathing, fall in blood pressure, severe stomach cramps) is known as ________.

anaphylactic shock

All of the following represent physical and/or chemical barriers that form the body's first line of defense against pathogens EXCEPT which one?

antibodies

Vaccines contain

antigens of the pathogen

Each of the following processes helps combat infection, EXCEPT __________.

autoimmunity

Skin is able to prevent most microorganisms from entering the body by

having keratin in the uppermost layer

Inflamed tissue turns red because ________.

there is an increased blood flow to the injured tissues due to dilation of arterioles in the injured area

The best way to defend the body from a viral infection is to prevent the infection by using a vaccine.

true

The following are steps in phagocytosis: (1) Bacterium is digested by lysosomal enzymes; (2) phagocyte approaches bacterium; (3) phagocytic vesicle fuses with lysosome; and (4) phagocyte engulfs bacterium, forming a phagocytic vesicle. In which order do these steps occur?

2-4-3-1

The direct cause of the heat generated by a wound or local infection is ________.

HISTAMINE, which causes the smooth muscle cells of the arterioles to relax; this leads to a cascade of events causing the tissue to become hot

A specific antibody will bind to __________.

a specific antigen

Antibiotics are most likely to be effective in the treatment of infections caused by

bacteria

Antibiotics kill bacterial cells but do not (usually) damage human cells by taking advantage of the difference between human and bacterial cells. These differences include

bacterial cells have cell walls, human cells do not

True or false. When you suffer an injury, white blood cells near the injury site initiate the inflammatory response.

false

Major histocompatibility complex (MHC) proteins __________.

identify a body cell as "self"

The advantage of having memory cells in specific defenses is that

if exposed to an antigen a second time, they quickly become plasma cells

The primary immune response is __________.

less effective than the secondary immune response

Which of the following body fluids does not transmit HIV from human to human?

saliva

Autoimmune disorders occur when __________.

the immune system fails to recognize "self" cells