Chapter 15 (Unit 4 Exam)

Question 1

How is the lymphatic system connected to the circulatory system?

Options:
A) Through the airways
B) By a series of electrical impulses
C) Via lymphatic vessels that drain into blood vessels
D) There is no direct connection

Answer 1

C) Via lymphatic vessels that drain into blood vessels

Explanation: The lymphatic system is connected to the circulatory system through lymphatic vessels that drain lymph fluid carrying immune cells back into the bloodstream.

Question 2

Select all the statements that pertain to the principle of herd immunity.

Check All That Apply
A) Immune individuals do not carry the agent of a particular communicable disease.
B) Mass immunization confers indirect protection of non-immunized members.
C) Encounter with a pathogen is more likely in a largely immunized population.
D) Herd immunity is only maintained through the occurrence of natural disease.
E) Low herd immunity means there are greater numbers of susceptible individuals.

Answer 2

A) Immune individuals do not carry the agent of a particular communicable disease.
B) Mass immunization confers indirect protection of non-immunized members.
E) Low herd immunity means there are greater numbers of susceptible individuals.

Explanation: Herd immunity is based on the fact that an immunized population will not carry the disease pathogen. Thus, susceptible individuals are indirectly protected due to decreased risk of exposure to the pathogen.

Question 3

Which of the following are the four major categories of innate immunity?

Options:
A) Inflammation, phagocytosis, complement system, and adaptive immunity
B) Phagocytosis, inflammation, fever, and antimicrobial products
C) Skin, mucus membranes, natural killer cells, and antimicrobial peptides
D) T cells, B cells, antimicrobial proteins, and interferons

Answer 3

B) Phagocytosis, inflammation, fever, and antimicrobial products

Explanation: The four major categories of innate immunity include phagocytosis (the engulfment and digestion of pathogens), inflammation (a response to infection or injury), fever (an elevated body temperature that hinders pathogen proliferation), and antimicrobial products (like interferons and the complement system).

Question 4

Three kinds of blood cells that function in innate immunity include neutrophils, __________, and macrophages.

Answer 4

Monocytes

Explanation: Neutrophils, monocytes, and macrophages are blood cells that play a critical role in innate immunity. They are involved in processes like phagocytosis, which helps the body to quickly respond to infections.

Question 5

The body systems that participate in immunity include the __________, lymphatic system, and __________ systems.

Answer 5

Circulatory, endocrine

Explanation: The circulatory and lymphatic systems are key participants in immunity, with the circulatory system transporting cells and proteins involved in the immune response, and the lymphatic system providing an environment for immune cells to mature and interact.

Question 6

Four types of antimicrobial host-derived products include interferons, the complement system, antimicrobial peptides, and __________.

Answer 6

Restriction factors

Explanation: The body produces various antimicrobial substances that act against pathogens. Restriction factors are proteins that inhibit viral replication, complement aids in destroying pathogens, interferons have antiviral activity, and antimicrobial peptides can destroy a wide range of microbes.

Question 7

Normal microbiota do not contribute to the first line of defense in the immune system.

A) True
B) False

Answer 7

B) False

Explanation: Normal microbiota play a crucial role in the first line of defense by providing microbial antagonism, which includes competing for nutrients and attachment sites and altering the pH to inhibit the growth of pathogens.

Question 8

The complement system is activated via which of the following pathways?

Options:
A) Classical, lectin, and alternative pathways
B) Direct, indirect, and passive pathways
C) Innate, adaptive, and passive pathways
D) Active, inactive, and transitional pathways

Answer 8

A) Classical, lectin, and alternative pathways

Explanation: The complement system can be activated by three different pathways: classical, lectin, and alternative. Each pathway is initiated in different ways but ultimately contributes to the destruction of pathogens.

Question 9

How does fever help defend the body?

Options:
A) By slowing down the immune response
B) By creating a more favorable environment for bacteria to grow
C) By inhibiting the multiplication of temperature-sensitive microorganisms and activating immune defenses
D) Fever has no role in defending the body

Answer 9

C) By inhibiting the multiplication of temperature-sensitive microorganisms and activating immune defenses

Explanation: Fever helps defend the body by inhibiting the growth of temperature-sensitive pathogens and by enhancing the activity of certain immune cells and the breakdown of cellular debris.

Question 10

Complement factors C5b+C6+C7+C8 make up a membrane attack complex that results in:

Multiple Choice

A) opsonization.
B) lysis of cell.
C) enhanced phagocytosis.
D) All of these choices are correct.

Answer 10

B) lysis of cell.

Question 11

The four body systems that participate in the first line of defense include the integumentary, __________, respiratory, and __________ systems.

Answer 11

Digestive, genitourinary

Explanation: The first line of defense includes the integumentary system (skin), digestive system (stomach acid, gut flora), respiratory system (nasal hairs, mucus), and genitourinary system (acidic pH of the urine, mucus).

Question 12

The steps of inflammation include pain, redness, heat, and swelling, but not impairment of function.

A) True
B) False

Answer 12

B) False

Explanation: The classic signs of inflammation are pain (dolor), redness (rubor), heat (calor), swelling (tumor), and loss of function. Impairment of function is a significant component of inflammation.

Question 13

T and B lymphocytes mature in which of the following locations?

Options:
A) Thymus and bone marrow
B) Spleen and thymus
C) Bone marrow and liver
D) Spleen and lymph nodes

Answer 13

A) Thymus and bone marrow

Explanation: T lymphocytes mature in the thymus, and B lymphocytes complete their maturation in the bone marrow. This maturation process is essential for adaptive immunity.

Question 14

What is the role of the skin in the first line of defense?

Options:
A) Produces antibodies
B) Acts as a physical barrier
C) Is the primary site of phagocytosis
D) Detects temperature changes

Answer 14

B) Acts as a physical barrier

Explanation: The skin acts as a physical barrier that is tough and impermeable, preventing the penetration of pathogens.

Question 15

Fever is regulated by the hypothalamus and can be triggered by substances called _______.

Answer 15

Pyrogens

Explanation: Fever, an abnormally elevated body temperature, is often a response to infection and can be triggered by pyrogens, which are substances that cause the hypothalamus to raise the body’s temperature set point.

Question 16

Cytokines are important because they __________, and an example of a pro-inflammatory cytokine is __________.

Answer 16

Signal and coordinate immune responses, Interleukin-1 (IL-1)

Explanation: Cytokines are crucial for signaling and coordinating immune responses, including inflammation and cell activation. Interleukin-1 (IL-1) is a pro-inflammatory cytokine that plays a role in the development of fever and the promotion of inflammation.

Question 17

A “marker” is a molecule that triggers an immune response in the first line of defense.

A) True
B) False

Answer 17

B) False

Explanation: Markers, also known as antigens, are molecules on the surface of cells that are recognized by the immune system. They are crucial in the second and third lines of defense for the immune system to differentiate between self and nonself entities.

Question 18

What is the function of cytokines in the immune response?

Options:
A) Carry oxygen to tissues
B) Generate nerve impulses
C) Signal and coordinate immune reactions
D) Provide structural support for cells

Answer 18

C) Signal and coordinate immune reactions

Explanation: Cytokines are chemical messengers produced by immune cells that signal and coordinate various aspects of the immune response, including inflammation and cell activation.

Question 19

The mononuclear phagocyte system includes macrophages located in various organs, like Kupffer cells in the _______.

Answer 19

Liver

Explanation: The mononuclear phagocyte system consists of macrophages scattered throughout the body, including Kupffer cells in the liver, which function to engulf and degrade foreign molecules.

Question 20

The complement system acts as a second line of defense by marking pathogens for destruction, and interferons are specific to individual viruses.

A) True
B) False

Answer 20

B) False

Explanation: The complement system indeed marks pathogens for destruction and can directly lyse them. However, interferons are not virus-specific; they are host-specific proteins that provide a broad antiviral response.

Question 21

Select the statements that accurately describe antigens.

Check All That Apply

A) They are perceived as foreign.
B) Only whole microbes can serve as antigens.
C) Proteins are immunogenic antigens.
D) Antigens provoke an immune response.

Answer 21

A) They are perceived as foreign.
C) Proteins are immunogenic antigens.
D) Antigens provoke an immune response.

Explanation: Antigens, which can be proteins, provoke an immune response because they are perceived as foreign.

Question 22

The steps of phagocytosis include chemotaxis, adherence, ingestion, digestion, and __________.

Answer 22

Excretion

Explanation: Phagocytosis is the process by which phagocytes engulf and digest microorganisms and cellular debris. The final step is excretion, where the phagocyte eliminates residual material.

Question 23

The mononuclear phagocyte system is unrelated to innate immunity.

A) True
B) False

Answer 23

B) False

Explanation: The mononuclear phagocyte system is integral to innate immunity. It includes monocytes and macrophages that are involved in phagocytosis and other defensive actions against foreign invaders.

Question 24

The initial reaction to the presence of viruses in a human cell is the production of _________blank by that cell.

Multiple Choice
A) interferon
B) antimicrobial proteins
C) complement
D) fever

Answer 24

A) interferon

Question 25

Which type of white blood cell is responsible for early responses to pathogens by phagocytosis and is a primary component of pus?

Options:
A) Basophils
B) Eosinophils
C) Neutrophils
D) Monocytes

Answer 25

C) Neutrophils

Explanation: Neutrophils are white blood cells that react early to infection and are primary components of pus, indicating their role in phagocytosis and response to bacterial infection.

Question 26

What are the three components of the first line of defense in the immune system?

Options:
A) Skin, mucus membranes, and antimicrobial proteins
B) T cells, B cells, and antibodies
C) Inflammation, fever, and phagocytosis
D) Lymph nodes, spleen, and Peyer’s patches

Answer 26

A) Skin, mucus membranes, and antimicrobial proteins

Explanation: The first line of defense consists of barriers that block invasion at the portal of entry and include physical barriers like skin, mucus membranes, and various antimicrobial substances.

Question 27

The primary lymphatic organs include the lymph nodes and spleen.

A) True
B) False

Answer 27

B) False

Explanation: The primary lymphatic organs are the red bone marrow and thymus, which are the birthplaces of lymphocytes. The lymph nodes and spleen are considered secondary lymphatic organs, which are the sites of immune cell action.

Question 28

What are the three lines of host defenses?

Options:
A) Structural, cellular, biochemical
B) Innate immunity, adaptive immunity, passive immunity
C) First line, second line, third line
D) Physical barriers, antibodies, T cells

Answer 28

C) First line, second line, third line

Explanation: The three lines of host defenses include the first line (physical and chemical barriers), the second line (nonspecific cellular and chemical systems), and the third line (acquired immunity with specific responses).

Question 29

Mucus membranes in the respiratory tract protect against pathogens by trapping them in a layer of _______.

Answer 29

Mucus

Explanation: Mucus membranes in the respiratory tract trap pathogens in mucus, which is then moved by cilia and expelled from the body, providing a protective mechanism against infection.

Question 30

The normal microbiota is part of the _________blank line of defense.

Multiple Choice
A) fourth
B) third
C) second
D) first

Answer 30

D) first

Question 31

Cytokines are secreted by which cells?

Multiple Choice
A) Macrophages
B) T cells
C) All of these cells can secrete cytokines.
D) B cells

Answer 31

C) All of these cells can secrete cytokines.

Question 32

Tears do not contribute to the first line of defense.

A) True
B) False

Answer 32

B) False

Explanation: Tears contribute to the first line of defense by washing away irritants and pathogens from the eye, and contain lysozyme which can lyse bacterial cells.

Question 33

Interferons are virus-specific proteins that protect cells from infection.

A) True
B) False

Answer 33

B) False

Explanation: Interferons are not virus-specific; they are proteins that can protect cells from various viral infections by interfering with viral replication within host cells and activating immune cells.