Question 1

Which of the following does not provoke inflammation?

Accepted Answer

Tickling does not cause any tissue damage or introduction of foreign material, which are necessary for inflammation to occur. Instead, tickling activates the nervous system and triggers laughter or other reflex reactions.

Question 2

Choose the item that would provoke a cell to produce interferons.

Accepted Answer

Interferons are produced in response to viral infections. Chemical irritants, bacteria, and fungi may activate other components of the immune system, but they do not typically induce interferon production.

Question 3

Interleukin-1 secretion causes

Accepted Answer

Interleukin-1 is a pro-inflammatory cytokine that is produced by white blood cells in response to infection or injury. It plays a crucial role in initiating immune responses, resulting in a fever as a means of fighting off the infection.

Question 4

Innate defenses are

Accepted Answer

Innate defenses are fast and nonspecific. They are the body's first line of defense against pathogens and are not tailored to specific pathogens but provide a general response. Examples of innate defenses include physical barriers, such as the skin and mucous membranes, and chemical barriers, such as enzymes and acids in saliva and stomach acid.

Question 5

A transplant recipient rejects a transplanted organ because her ________ does not match that of the donor closely enough.

Accepted Answer

The major histocompatibility complex (MHC) is a set of genes that encode for cell surface molecules that are involved in the recognition and presentation of antigens to the immune system. MHC mismatch between donor and recipient increases the risk of rejection, as the recipient's immune system views the transplanted organ as foreign and mounts an immune response against it. This is a major barrier to successful organ transplantation and requires careful matching between donor and recipient to minimize the risk of rejection.

Question 6

Which of the following is not a mechanical barrier against microorganisms?

Accepted Answer

Saliva, urine, and tears all have mechanical properties that function as barriers against microorganisms. For example, saliva can wash away bacteria and viruses from the mouth and tears can flush out foreign particles from the eye. Diarrhea, on the other hand, is a symptom of gastrointestinal distress and is not a mechanical barrier against microorganisms.

Question 7

A person has a rare autoimmune disorder in which immune cells attack and destroy thymosins as soon as they are produced and secreted. What affect will this have on the immune system?

Accepted Answer

Thymosins play a crucial role in the maturation of T lymphocytes in the thymus gland. If the immune cells are attacking and destroying thymosins as soon as they are produced and secreted, T lymphocytes will not be able to mature and the person will be severely immunocompromised. This can lead to a range of health problems, including increased susceptibility to infections and an inability to mount an effective immune response.

Question 8

Which of the following examples best demonstrates species resistance?

Accepted Answer

Species resistance is the ability of a host species to resist infection from a pathogen that can infect other, similar host species. In this case, the worker at the animal shelter encounters a cat with Calicivirus but cannot become sick with it themselves. This demonstrates species resistance as humans are not the natural host for Calicivirus, and therefore have some level of protection against it. The other options do not demonstrate species resistance as they involve pathogens spreading between multiple host species or infecting both animals and humans.

Question 9

The mononuclear phagocytic system includes

Accepted Answer

The mononuclear phagocytic system, also known as the reticuloendothelial system, primarily consists of monocytes and macrophages. Neutrophils, while also important in the immune response, are part of the granulocyte family rather than the mononuclear phagocyte system.

Question 10

Which response is slower but more specific for a pathogen?

Accepted Answer

Adaptive defenses are slower to respond than innate defenses, but they are more specific for a particular pathogen. Adaptive defenses involve the production of antibodies and the activation of certain immune cells that target a specific pathogen.

Question 11

A virus differs from other pathogens in that it is

Accepted Answer

A virus cannot reproduce outside a living cell and therefore requires a host to replicate. This distinguishes viruses from other pathogens such as bacteria and fungi which can grow and reproduce in non-living environments. Size and danger level can vary greatly among different types of pathogens and are not exclusive to viruses. Additionally, viruses are not multicellular as they consist of only a nucleic acid core surrounded by a protein coat.

Question 12

The tissues of the spleen are called

Accepted Answer

The tissues of the spleen are divided into two main zones, the red pulp and white pulp. The red pulp is composed of venous sinuses filled with blood and specialized cells that filter and remove damaged or old blood cells. The white pulp contains lymphocytes, which are immune cells that help in the production of antibodies and fighting infections. Thus, the correct choice is A, red and white pulp. The other options are not correct descriptions of the tissues of the spleen.

Question 13

Which innate defense mechanism initiate(s)a cascade effect in response to foreign proteins in the body?

Accepted Answer

The complement system is a group of plasma proteins that interact with one another in a cascade of reactions, leading to the destruction of invading pathogens. This process is initiated by the presence of foreign proteins in the body. Therefore, the complement system is the innate defense mechanism that initiates a cascade effect in response to foreign proteins in the body.

Question 14

Marsha gets a splinter in her finger. What is her body's first response to any microbe that might try to enter her body as a result of the splinter breaking the skin?

Accepted Answer

The body's first response to any microbe that might try to enter the body through the broken skin is the innate defense. Innate defenses are non-specific and act as the first line of defense against many different types of pathogens. They include physical barriers, such as the skin, as well as chemical barriers, such as enzymes that protect against infection.

Question 15

The most active phagocytic cells in circulating blood are

Accepted Answer

Neutrophils and monocytes are the most active phagocytic cells in circulating blood. Neutrophils are the first cells to respond to an infection and are highly adept at phagocytosis. Monocytes are produced in the bone marrow and develop into macrophages when they enter tissues. Both neutrophils and monocytes are leukocytes (white blood cells) and play a critical role in the innate immune response.

Question 16

What is not true of the spleen?

Accepted Answer

The spaces in the lobes of the spleen are filled with blood, not lymph.

Question 17

DiGeorge syndrome is a chromosomal disorder in which the thymus never develops/barely develops due to a deletion in a chromosome. Which of the following complications would you expect a child with DiGeorge syndrome to encounter?

Accepted Answer

DiGeorge syndrome is characterized by the underdevelopment of the thymus, which is responsible for the maturation and differentiation of T lymphocytes. Therefore, a child with DiGeorge syndrome will have very few functional T lymphocytes, leading to immunodeficiency. Option A is incorrect because B lymphocytes are not affected in DiGeorge syndrome. Option B describes the role of the lymph nodes, which are not necessarily affected in DiGeorge syndrome. Option D describes lymphatic obstruction, which is not a characteristic of DiGeorge syndrome.

Question 18

Low-grade fever is an effective defense for short periods of time because it

Accepted Answer

Low-grade fever increases the body temperature, which slows down bacterial growth, making it more difficult for them to replicate and spread. This gives the immune system extra time to mobilize defenses and fight off the infection.

Question 19

Heliobacter pylori is a species of bacteria that causes stomach ulcers. It does this by burrowing into the mucosal lining of the stomach and degrading it to form a hole. By doing so, what type of innate defense is it overcoming?

Accepted Answer

Heliobacter pylori is overcoming the mechanical barrier provided by the mucosal lining of the stomach.

Question 20

The spleen

Accepted Answer

The spleen resembles a large lymph node divided into lobules.

Answer: D 
 The spleen filters lymph.

Therefore, the best choices are B and D.

Quiz 16: Lymphatic System and Immunity