Chapter 12 -The Lymphatic and Immune System Flashcards

1
Q

Functions of the immune system

A

Responsible for protecting humans against bacteria, viruses, fungi, toxins, parasites, and cancer

Works with the organs of the lymphatic system to clear the body of these disease-causing agents
Thymus, spleen, lymphatic vessels, lymph nodes, and lymphoid tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Lymphatic System Components and Functions

A

Network of connecting vessels that collects the interstitial (or tissue) fluid found between cells

Lymphatic vessels then return this fluid, now called lymph, to the bloodstream

Also picks up lipids and fat-soluble vitamins from the digestive tract and transports them to the bloodstream

Protects the body against disease-causing agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Interstitial Fluid and Lymph Fluid

A

Fluid constantly leaks out of blood capillaries into the spaces between cells
Increased tissue hydrostatic pressure moves interstitial fluid into the lymphatic vessels
Fluid is destined to become lymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Lymphatic Capillaries

A

Similar in structure to blood capillaries
Larger in diameter

Thin, very permeable walls
Lined by a single layer of squamous epithelial cells called endothelium

Epithelial cells overlap
Create flaplike valves that allow fluid to enter the capillary, but do not allow fluid to exit under normal conditions

Lymph can leak out of the vessels, causing edema or fluid buildup in the interstitial spaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Lymphatic Trunks

A
Named after the region in which they are found
Jugular trunks - Head and neck region
Lumbar trunk - Lower extremities
Subclavian trunk - Upper limbs
Bronchomediastinal trunk - Thorax
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Right lymphatic duct

A

Receives lymph from the upper right side of the body
Empties its contents into the right internal jugular and right subclavian veins
Return the lymph to the right atrium by way of the superior vena cava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Thoracic duct

A

Drains lymph from all parts of the body that are not drained by the right lymphatic duct
Begins at the level of the second lumbar vertebra and has a dilated sac or channel called the cisterna chyli
Empties into the junction of the left internal jugular and left subclavian veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Lymphatic Movement

A

Lymph is moved along towards the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Skeletal muscle pump

A

Utilizes skeletal muscle contractions to move the lymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Respiratory pump

A

Utilizes pressure changes in the thorax to assist circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lymphatic Pathway

A

Lymphatic Capillary >Afferent Lymphatic vessel> lymph node> Efferent Lymphatic vessel >Lymphatic trunk>collecting duct >Subclavian trunk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lymphedema

A

Blockage of lymphatic vessels

Caused by genetics, parasitic infections, trauma to the vessels, tumors, radiation therapy, cellulitis, and surgeries (mastectomies and biopsies).
Tissue swelling that lasts longer than a few days or increases over time
compression stockings . maintain good nutrition . keep skin clean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Lymph Nodes

A

Very small, glandular structures
Located along the paths of larger lymphatic vessels
Spread throughout the body

Indented side is called the hilum- Nerves and blood vessels enter
Afferent lymphatic vessels -Carry lymph to the node
Efferent lymphatic vessels - Carry lymph out of a node are called efferent vessels
Lymph tends to concentrate in the node.- Pressure builds up that assists in filtration
Surrounded by a fibrous capsule of connective tissue
Medulla- Inner portion
Cortex- Outer portion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Macrophages and lymphocytes

A

Together these form the lymph nodules
Lymph nodules are found in the cortex.
Macrophages digest unwanted pathogens in the lymph.
Lymphocytes are part of the immune response against the pathogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Viral or bacterial infection, causes lymphadenitis

A

Inflammation of the lymph nodes
Any disease of the lymph nodes is called lymphadenopathy
Terms lymphadenitis and lymphadenopathy are often used interchangeably

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Thymus

A

Soft, bilobed organ
Located behind the sternum, just below the thyroid gland and above the heart
Large in the infant
Maximum size, 1 to 2 ounces, when the child is about two years of age
After adolescence, atrophies or involutes
In older adults, tiny or almost nonexistent

Produces the hormone thymosin
Stimulates the production of mature lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Cortex of thymus

A

Outer portion

Where T lymphocytes (T cells) that have been produced in the bone marrow proliferate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Medulla of thymus

A

Inner portion

T cells move to and mature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Spleen

A

Located in the upper-left quadrant of the abdominal cavity
Below the diaphragm and behind the stomach
Protected by the rib cage
Divided into lobules with two types of tissues
White pulp is concentrated with lymphocytes.
Red pulp has an abundance of red blood cells, lymphocytes, and macrophages.

Filters blood and removes worn-out red blood cells from the bloodstream
Splenomegaly- Injured or becomes enlarged due to disease
Splenectomy- Removed to prevent rupture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lymphatic Nodules

A

Masses of lymphatic tissue not surrounded by a capsule

Often referred to as mucosa-associated lymphoid tissue (MALT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Tonsils

A

Lymphatic Nodules
Tonsils are three sets of lymphoid tissue
Form a ring known as the Ring of Waldeyer
Pharyngeal tonsils or adenoids
Junction of the mouth and oropharynx
Palatine tonsils
Junction of the nasal cavity and nasopharynx
Lingual tonsils
Located at the base of the tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Appendix, or vermiform appendix

A

Lymphatic Nodules
Located in the lower-right quadrant at the junction of the large and small intestines
Once thought to have no function
Part of the immune system

Peyer’s patches
Located in the small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Disease Defenses

A

Immunity, also known as resistance
Divided into innate and acquired immunity
We are born with innate or nonspecific immunity.
Acquired or specific immunity takes place over a period of time after exposure to an antigen.
Disease may take the form of injury, infection, or malignancy.
Infection is the presence of a pathogen in or on the body.
Pathogen is a disease-causing agent such as a bacterium, virus, toxin, fungus, or protozoan.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Zoonotic disease

A

Disease that is transmissible from an animal to humans

25
Phagocytosis
Innate (Nonspecific) Defenses Neutrophils and monocytes have phagocytic characteristics Monocytes are transformed into macrophages. Very large and active phagocytes capable of ingesting very large particles Neutrophils, monocytes, and macrophages make up what is called the mononuclear phagocytic system or the reticuloendothelial system
26
Physical barriers
Skin and the mucosa that line the digestive tract, oral cavity, and other areas First line of defens
27
Chemical barriers
Chemicals and enzymes in body fluids provide barriers that destroy pathogens Along with the remaining nonspecific mechanisms, form the second line of defense
28
Natural killer (NK) cells
Innate (Nonspecific) Defenses Natural killer (NK) cells Type of lymphocyte which primarily targets cancer cells Like cytotoxic T cells, NK cells kill harmful cells on contact Secrete chemicals called perforins that punch holes in the membranes of harmful cells Unlike B and T cells, NK cells do not have to rely on memory to recognize a specific antigen to start destroying pathogens
29
Inflammation
Innate (Nonspecific) Defenses Inflammation Injury or infection cause this vascular response Cardinal signs Heat, swelling, erythema, pain, and loss of function Blood vessels in the injured area first constrict then dilate Also become more permeable or “leaky” Neutrophils and monocytes Leave the blood vessels to fight the infection Clean up the area
30
Acquired (Specific) Defenses
Another name for immunity, the third line of defense | Classified as cellular or humoral immunity
31
Antigens
Defined as foreign substances in the body Pathogens have many antigens on their surfaces Haptens - Combine with larger proteins in the blood to make them capable of eliciting an immune response
32
B cells
Do not attack antigens directly | Respond to antigens - Becoming plasma cells or memory B cells
33
Plasma cells
Make antibodies that are directed against a specific antigen Antibodies attach to the antigens in the humors (fluids) of the body. Humoral immunity or antibody-mediated response
34
Memory B cells
Recognize the antigen the next time exposure to the same antigen occurs Stronger and more immediate response results
35
T cells
Go to the thymus to mature or be processed Bind to antigens on cells and attack them directly Called a cell-mediated response, or cellular immunity Respond to antigens by secreting cytokines called lymphokines
36
T cell activation
Macrophage ingests and digests a pathogen that has antigens on it Takes some of the antigens from the pathogen and puts them on its cell membrane next to a large protein complex called a major histocompatibility complex (MHC) Another name is human leukocyte antigens (HLAs). T cell that has a receptor for the antigen recognizes and binds to the antigen and the MHC on the surface of the macrophage T cell is now activated and begins to divide to form other types of T cells
37
Cytotoxic T cells
Protecting the body against viruses and cancer cells
38
Helper T cells
Increase antibody formation, memory cell formation, B-cell formation, and phagocytosis
39
Memory T cells
“Remember” the pathogen that activated the original T cell
40
Compare origin of undifferentiated T cell vs b cells
Both in red bone marrow
41
Compare site of differentiation T cell vs b cells
Tcells - Thymus | Bcells- Red bone Marrow
42
Compare primary locations of T cell vs b cells
T and Bcells - lymphatic tissues - circulating lymphocytes in blood
43
Compare primary fuctions of T cell vs b cells
Tcell - provide cellular immune response where t cells interact directly with the antigens or antigen bearing agents to destroy them Bcells- provide humoral immune response where b cells interact directly producing antibodies that destroys the antigens or antigen bearing agents
44
Antibodies
``` Called immunoglobulins (Ig) Proteins produced by plasma cells ``` Antibodies bind to antigens, they take one of the following three actions - Allow phagocytes to recognize and destroy antigens - Make antigens clump together, causing them to be -destroyed by macrophages - Cover the toxic portions of antigens to make them harmless
45
Primary immune system response
First time a person is exposed to an antigen Slow and takes several weeks to occur Memory cells are produced
46
Secondary immune system response
Next time a person is exposed to the same antigen Very quick and usually prevents a person from developing a disease Memory cells carry out this response
47
Naturally Acquired Active Immunity
Naturally exposed to an antigen Make antibodies and memory cells Long lasting
48
Artificially Acquired Active Immunity
Injected with a pathogen Make antibodies and memory cells Long lasting
49
Transplantation and Tissue Rejection
Tissues and organs that are transplanted Cornea, kidney, lung, pancreas, bone marrow, skin, liver, and heart Transplanted tissue may actually cause harm to the host’s tissues Graft-versus-host disease (GVHD) MHC of the host or recipient and the possible donor are examined for a match
50
Autograft
From the person’s own body
51
Isograft
From an identical twin
52
Allograft
From someone other than the individual or an identical twin
53
Xenograft
From another species, such as a pig or other primate
54
Immunosuppressive drugs
Given to help reduce the risk of Transplantation and Tissue Rejection Serious side effects such as infection, kidney damage, and even cancer
55
Allergic reaction
Excessive immune response to a stimulus Substances that trigger allergic responses are called allergens Allergic reactions involve IgE antibodies and mast cells IgE antibodies bind to allergens, they cause mast cells to release histamine and heparin
56
Autoimmune Disease
Failure of self-recognition Body does not recognize a part of itself Considers it “foreign” and attacks its own antigens Much more common in women First lines of treatment Corticosteroids to control the inflammatory response
57
Mononucleosis
Highly contagious viral infection Spread through the saliva of the infected person Caused by either the Epstein-Barr virus or the cytomegalovirus Symptoms Unexplained fever, extreme fatigue, sore throat, weakness, headache, and swollen, tender lymph nodes Rest, proper nutrition, and antibiotics to prevent secondary infections usually result in recovery from acute symptoms.
58
HIV/AIDS
AIDS is caused by HIV, and is spread in three ways: - Sexual contact with someone who is HIV-positive - Sharing needles with someone who is HIV-positive - Mother to fetus or infant through the placenta during the birth process or through breast milk HIV attacks specific lymphocytes called T lymphocytes Places the individual at risk of contracting many other potentially fatal diseases T-cell counts below 200; No cure for AIDS