Science Olympiad -Anatomy and Physiology Immune System Questions

1. disease causing organisms / infectious agents.

2. malfunctioning or abnormal body cells (ei cancer)

3. foreign cells or particles.

The immune system is the body's defense against what 3 things?

Autoimmunity

What is an immune reaction against self molecules called?

Self and non-self

Basic immunity depends on the ability of the immune system to distinguish between what type of molecules?

Self molecules

What type of molecules help the immune system identify components of the body?

Non-self molecules

What type of molecules help the immune system identify foreign agents in the body?

Antigens (short for antibody generators) are substances that bind to specific immune receptors and elicit an immune response.

What are antigens?

1. Specific cells

2. Lymphatic organs

3. Diffuse lymphatic tissue

What are the 3 main components of the immune system?

Bone marrow

Specific cells of the immune system originate from precursor cells in what tissue?

Thymus, spleen, tonsils, and lymph nodes.

What are the organs in the lymphatic system?

Digestive tract, respiratory system, and the skin.

The diffuse lymphatic tissue includes collections of immune cells dispersed where in the body?

1. Leukocytes

2. Plasma cells

3. Macrophages

4. Mast cells

What are the 4 types of immune cells?

Plasma cells

Which type of immune cells make and secrete antibodies?

Mast cells

Which type of immune cells trigger an inflammatory response?

Macrophages

Which type of immune cells engulf foreign particles and are found outside the blood vessels in tissues?

Neutrophils

Basophils

Eosinophils

Monocytes

Lymphocytes

What are the 5 types of leukocytes?

Lymphocytes

Which type of immune cells elicit the specific immune response?

B cells

Cytotoxic T cells

Helper T cells

NK cells

What are the 4 types of lymphocytes?

Helper T cells

Which type of immune cells are attacked by HIV?

Helper T cells

Which type of immune cells help activate B cells and cytotoxic T cells?

Cytotoxic T cells

Which type of immune cells recognize and attack cancerous and infected cells?

B cells

Which type of immune cells recognize foreign antigens and secrete antibodies?

Lymph nodes

What are the small round structures found at points along lymphatic vessels that have fibrous connective tissue capsule with incoming and outgoing lymphatic vessels?

Lymphocytes and macrophages

Lymph nodes contain sinuses filled with what type of cells?

Axillary (armpits) and inguinal (groin)

What 2 regions of the body are lymph nodes located?

Tonsils

(Waldeyer's ring)

Name of the lymph nodes located in the back of the mouth.

Adenoids

(Pharyngeal tonsils)

Name of the lymph nodes located on the posterior wall of the soft palate.

Peyer's patches

Name of the lymph nodes located within the intestinal wall.

Left upper abdomen beneath the diaphragm.

Where is the spleen located?

Blood

The spleen is divided by connective tissue into lobules with sinuses filled with what?

Spleen

What organ functions as a blood reservoir making blood available when pressure is low?

Red pulp

What part of the spleen contains RBCs, lymphocytes, and macrophages?

Red pulp

What part of the spleen functions to remove bacteria and worn-out RBCs?

Spleen (both red and white pulp)

What organ helps to purify the blood?

Thymus

What organ is located along the trachea behind the sternum?

Thymus

What organ is largest in children and disappears in old age?

Inner lobule (medulla) of thymus

Where is thymosin secreted?

Thought to aid T cells to mature.

What does thymosin do?

Red bone marrow

Where do all types of blood cells originate from?

Stem cells

What type of cells continuously divide to produce cells that differentiate into various blood cells?

Almost all

In children red bone marrow is found in which bones?

Skull, sternum, ribs, clavicles, spinal column, femur, and humerus

In adults red bone marrow is found in which bones?

Reticular cells

Red bone marrow has a network of connective tissue fibers produced by what type of cells?

Reticular and stem cells

The sinuses of red bone marrow is filled with what type of cells?

Differentiated (the stem cells has changed into a specific type of immune cell).

Are the cells that leave the red bone marrow and enter the blood stream differentiate or undifferentiated?

Gut-Associated Lymphatic Tissue

GULT

What part of the immune system is located in the intestinal wall and contains lymphocytes, plasma cells and macrophages?

The intestines

Where is the largest mass of lymphoid tissue in the body?

Aggregates in appendix & large intestine

Accumulates with age in stomach

Small aggregates in esophagus

Diffusely distributed cells in GI tract lining

In addition to the tonsils, adenoids, and Peyer's patches, where else is lymphoid tissue found in the gastrointestinal system?

Mucosa-associated Lymphatic Tissue

MALT

What is the lymphoid tissue associated with the mucosa of the female reproductive tract, respiratory tract, etc. called?

Skin-Associated Lymphatic Tissue

SALT

What is the lymphoid tissue associated with the dermis of the skin called?

1st Line - Block entry

2nd Line - Fight Local Infections

3rd Line - Combat Major Infections

The body's immunity involves what 3 lines of defense?

Immunity

____________ is the ability to defend against infectious agents, foreign cells and abnormal cells eg. cancerous cells.

Nonspecific (innate) Response

Which type of immune response responds quickly and fights all types of invaders?

Specific (Adaptive) Response

Which type of immune response responds takes longer to react and works on specific types of invaders which it identifies and targets for destruction?

First line of defense - intact skin/mucosae and secretions of these membranes prevent entry of microorganisms.

Second line of defense - phagocytic white blood cells, antimicrobial proteins, and other cells

What of the line(s) of defense that the nonspecific immune response employ(s)?

Third line of defense - mounts attack against particular foreign substances via lymphocytes and antibodies

Which of the line(s) of defense that the nonspecific immune response employ(s)?

Nonspecific (Innate) Response

The inflammatory response is a key component of which type of immune response?

Skin, mucous membranes, nasal hairs, acidic fluids, natural flora, cerumen

What are some of the non-specific barriers that are part of the 1st line of defense?

They produce mucus which traps foreign particles and directs them out of the body.

How do the mucous membranes that line the entrances of the body provide a physical / mechanical barrier?

Nasal hairs

What structures trap foreign particles in the nasal cavity?

Low or acidic

Many body secretions provide protection because their pH is ______________________.

Natural flora

What are the harmless bacteria in intestines and vagina that prevent pathogens from growing called?

Cerumen (ear wax)

What secretion protects the ear canal?

2nd line of defense

Which line of defense fights local infection with an inflammatory process?

1st and 2nd lines of defense

Which lines of defense do not require immunological memory?

Phagocytosis

What process is an important feature of innate immunity that involves cell engulfing pathogens or particles?

Bone marrow

Where are phagocytes produced?

Scavengers

Which type of cells remove dead cells and microorganisms?

Complement

____________ proteins activate other proteins in a domino fashion resulting in a cascade of reactions.

1. attract phagocytes to invasion site

2. bind to the surface of microbes to insure WBC's can phagocytize the microbe

3. produce holes in the bacterial cell walls and membranes

What are the 3 events that the complement protein cascade of reactions initiate?

Redness (hyperemia), pain, swelling (edema), and heat

What are the main signs and symptoms of the inflammatory process?

Granulocyte - neutrophil

Macrophages

Which WBC has a primary function of phagocytosis?

Granulocyte - basophil

Which WBC has a primary function of producing histamine?

Granulocytes - Eosinophils

Which WBC has a primary function of producing toxic proteins against certain parasites?

Monocytes

Which WBC matures to become macrophages?

Natural Killer (NK) cells

Which WBC has a primary function of destroying target cells by cytolysis and apoptosis?

T cells

Which WBC has a primary function of cell-mediated immunity?

B cells

Which WBC become plasma cells which produce antibodies?

Neutrophils

These are characteristics of which type of immune cell?

60% of WBCs; 'Patrol tissues' as they squeeze out of the capillaries; Large numbers are released during infections; Short lived - die after digesting bacteria; Make up a large proportion of puss

Monocytes

These are characteristics of which type of immune cell?

Chief phagocytes found in the blood; Circulate in the blood for 1-2 days before they reach organs.

Macrophages

These are characteristics of which type of immune cell?

Found in the organs, not the blood; Larger than neutrophils and long lived; Involved in phagocytosis; Release interferon and interleukin

Macrophages

These are characteristics of which type of immune cell?

Act as scavengers; Versatile cells that reside within tissues and produce a wide array of chemicals; Antigen-presenting cells that activate the adaptive immune system.

Basophils

These are characteristics of which type of immune cell?

Capable of ingesting foreign particles; Produce heparin and histamine and which induce inflammation; Often associated with asthma and allergies.

Mast cells

These are characteristics of which type of immune cell?

Reside in connective tissues and mucous membranes; Regulate the inflammatory response; Often associated with allergy and anaphylaxis.

Dendritic cells

These are characteristics of which type of immune cell?

Phagocytes in tissues that are in contact with the external environment; Serve as a link between the innate and adaptive immune systems; Present antigens to T cells.

Eosinophils

Which type of immune cell is weakly phagocytic and kill parasitic worms?

Apoptosis

What is the process in which cells kill themselves called?

NK (natural killer) cells

Which type of immune cells are used to combat tumor cells or virus-infected cells?

NK (natural killer) cells

Which type of immune cells secrete interferons?

Proteins produced by virus infected cells which bind to receptors of non-infected cells, causing these cells to produce a substance that will interfere with viral reproduction and activate macrophages and other immune cells.

What are interferons?

Increased numbers of white blood cells in bloodstream.

What is leukocytosis?

When leukocytes cling to capillary walls.

What is margination?

When leukocytes pass through the capillary wall.

What is diapedesis?

1. Vasodilation of arteries

2. Increased capillary permeability

3. Chemotaxis (attraction of neutrophils, monocytes, and lymphocytes to area)

What are the 3 responses to the release of chemical mediators such as histamine and kinins?

When blood clots block an area to prevent injury to surrounding area.

What is the walling-off process?

Increased blood flow to area - causes heat and redness associated with inflammation.

What is local hyperemia?

The capillaries leak fluid (exudate formation) and fluid in tissue spaces (interstitial fluid). This causes pain and swelling.

What happens when capillary permeability increases?

Fibrin.

What type of "patch" forms the scaffolding for tissue repair?

It works on specific types of invaders which it identifies and targets for destruction - takes longer to react. The response is directed at specific targets and is not restricted to initial site of invasion/infection. Lag time occurs between exposure and maximal response. The adaptive immune system allows for a stronger immune response as well as immunological memory, where each pathogen is "remembered" by its signature antigen.

What is the specific (adaptive) response?

Proteins or carbohydrate chain of a glycoprotein within a plasma membrane which the body recognizes as "non-self."

What is an antigen?

Part of specific immune response which is antigen-specific and requires the recognition of specific "non-self" antigens. Antigen specificity allows for the generation of responses that are tailored to specific pathogens or pathogen-infected cells.

What is antigen presentation?