Immune and Digestive Systems

Question 1

This is present in all nucleated cells and displays endogenous antigens to cytotoxic T-cells (CD8+).

Answer 1

MHC Class I (MHC-I)

Question 2

Can punch holes in the cell walls of bacteria, making them osmotically unstable.

Answer 2

Complement System

Question 3

Are given off by virally infected cells and prevent viral replication and dispersion to nearby cells.

Answer 3

Interferons

Question 4

Ingest pathogens and present them on MHC (Major Histocompatibility Complex) molecules. They also secrete cytokines.

Answer 4

Macrophages

Question 5

This is present in professional antigen-presenting cells (macrophages, dendritic cells, some B-cells, and certain activated epithelial cells) and displays exogenous antigens to helper T-cells (CD4+).

Answer 5

MHC Class II (MHC-II)

Question 6

Antigen-presenting cells in the skin.

Answer 6

Dendritic Cells

Question 7

Attack cells not presenting MHC molecules, including virally infected cells and cancer cells.

Answer 7

Natural Killer Cells

Question 8

What are granulocytes?

Answer 8

• Neutrophills
• Eosinophills
• Basophills

Question 9

Ingest bacteria, particularly opsonized bacteria. They can follow bacteria using chemotaxis.

Answer 9

Neutrophils

Question 10

Are used in allergic reactions and invasive parasitic infections. They release histamine, causing an inflammatory response.

Answer 10

Eosinophils

Question 11

Are used in allergic reactions.

Answer 11

Basophils

Question 12

Related to basophils, but are found in the skin.

Answer 12

Mast Cells

Question 13

These cells lie in wait for a second exposure to a pathogen and can then mount a more rapid and vigorous immune response (secondary response).

Answer 13

Memory B and Memory T Cells

Question 14

What happens when an antigen-binding region is activated?

Answer 14

The region undergoes hypermutation to improve the specificity of the antibody produced. Cells may give signals for antibodies: to switch isotypes (IgA, IgD, etc.), to opsonize, cause agglutination or neutralize pathogens.

Question 15

Only selecting T-cells that can react to nonself antigens presented on MHC.

Answer 15

Positive Selection

Question 16

Causing apoptosis in self-reactive T-cells.

Answer 16

Negative Selection

Question 17

What peptide hormone promotes T-cell development?

Answer 17

Thymosin

Question 18

Respond to the antigen on MHC-II and coordinate the rest of the immune system, secreting lymphokines to activate various arms of immune defense.

Answer 18

Helper T-cells (CD4+)

Question 19

Secrete interferon-gamma, which activates macrophages.

Answer 19

Helper T-1 Cells (Th-1)

Question 20

Activate B-cells, primarily in parasitic infections.

Answer 20

Th-2 Cells

Question 21

Respond to antigens on MHC-I and promote self-tolerance.

Answer 21

Suppressor (Regulatory) T Cells

Question 22

A self-antigen is recognized as foreign and the immune system attacks normal cells.

Answer 22

Autoimmune Conditions

Question 23

A method of inducing active immunity prior to exposure to a particular pathogen.

Answer 23

Immunization

Question 24

Transfer of antibodies to an individual.

Answer 24

Passive Immunity

Question 25

What does the lymphatic system do?

Answer 25

• Balances fluid distribution
• Transports fats and fat-soluble compounds (inside chylomicrons)
• Site for mounting immune responses

Question 26

What type of digestion involves the oxidation of glucose and fatty acids to make energy?

Answer 26

Intracellular Digestion

Question 27

What type of digestion that occurs in the lumen of the alimentary canal?

Answer 27

Extracellular Digestion

Question 28

In the wall of the alimentary canal and controls peristalsis.

Answer 28

Enteric Nervous System (ENS)

Question 29

What hormones promote thirst?

Answer 29

ADH and Aldosterone

Question 30

What hormones promote hunger?

Answer 30

Glucagon and Ghrelin

Question 31

What hormones promote satiety?

Answer 31

Leptin and Cholecystokinin

Question 32

These cells secrete pepsinogen, a protease activated by the acidic enviornment of the stomach.

Answer 32

Chief Cells

Question 33

These cells secrete hydrochloric acid and intrinsic factor.

Answer 33

Parietal Cells

Question 34

This is important for vitamin B12 absorption.

Answer 34

Intrinsic Factor

Question 35

These cells secrete gastrin, a peptide hormone that increases HCl secretion and gastric motility.

Answer 35

G-cells

Question 36

Activates trypsinogen and procarboxypeptidases, initiating an activation cascade.

Answer 36

Enteropeptidase

Question 37

Stimulates the release of pancreatic juices into the digestive tract and slows motility.

Answer 37

Secretin

Question 38

Stimulates bile release from the gallbladder, release of pancreatic juices, and satiety.

Answer 38

Cholecystokinin

Question 39

These cells are in the pancreas and produce pancreatic juices that contain pancreatic enzymes (amylase, peptidase, or lipase) and bicarbonate.

Answer 39

Acinar Cells

Question 40

The liver synthesizes this; can be stored in the gallbladder or secreted into the duodenum directly.

Answer 40

Bile

Question 41

What does bile do?

Answer 41

It emulsifies fats and makes them soluble (also increasing their surface area).

Question 42

What are the main components of bile?

Answer 42

• Bile Salts
• Pigments like bilirubin (breakdown of Hgb)
• Cholesterol

Question 43

A vessel of the lymphatic system that is located in the villi of the small intestine.

Answer 43

Lacteal

Question 44

An outpocketing that accepts fluid from the small intestine through the ileocecal valve and is the site for the appendix attachment.

Answer 44

Cecum