Lymphatic System & Immunity

Question 1

Lymph

Answer 1

• Fluid left over in tissue spaces after blood capillaries have done their bit

Question 2

Lymphatic Capillaries

Answer 2

• being far leakier than blood capillaries (but with one-way valves that only let fluid in), move lymph out of tissue spaces and back toward blood circulation

Question 3

Order of Lymphatic System

Answer 3

• Lymphatic capillaries empty into
• lymphatic venules and then the larger lymphatic veins
  empty into two ducts:
  
  • The right lymphatic duct empties the upper right
    quadrant of the body, and
  • the largest of the lymphatic vessels, the thoracic duct
    “drains” the rest.

Question 4

Lacteals

Answer 4

• found in the wall of the small intestines

- move fats from the food that we digest into blood circulation

Question 5

Lymphedema

Answer 5

• When lymphatic vessels are blocked an tissues begin to swell due to an accumulation of lymph

Question 6

Elephantiasis

Answer 6

• a special kind of lymphedema
• due to lymphatic vessel blockage by parasitic worms.
• “elephant legs/feet”

Question 7

How do Lymph Nodes work? / Function

Answer 7

• As lymph moves along lymphatic vessels, it passes through lymph nodes, which are often found in clusters.
• F = lymph is filtered through the node; cells that have been infected by viruses, dead cells, and cancer cells can be removed.
  - assist from the immune system, whose cells can
  “eat” (phagocytize) or chemically-disassemble them,
  to prevent them from entering blood circulation

Question 8

Afferent + Efferent Lymphatic Vessels

Answer 8

• Afferent = Vessels entering a lymph node

- Efferent = Vessels exiting a lymph node

Question 9

Thymus - Location and Function

Answer 9

• L = in the mediastinum

- F = where T cells mature

Question 10

Palatine Tonsils

Answer 10

• are located on each side of the throat

Question 11

Lingual Tonsils

Answer 11

• located at the back of the tongue

Question 12

Pharyngeal Tonsils

Answer 12

• located in the throat, adjacent to the nasal cavity.

- also called adenoids

Question 13

Tonsilitis

Answer 13

• chronic inflammation of the tonsils

Question 14

Spleen - Location and Function

Answer 14

• L = in the ULQ of the abdomen
• F = serves as a reservoir of blood
  - It’s a location of immune system activity by
  removing bacteria, dead or damaged red blood
  cells, from which it recovers iron
  
  • involved in tissue repair

Question 15

Innate Immunity = Nonspecific Immunity

Answer 15

• immunity that we’re born with
• provides a general protection but doesn’t respond to specific pathogens
• physical barriers: skin, secretions of tears and mucous, and phagocytic cells that “eat” foreign bodies

Question 16

Adaptive Immunity = Specific Immunity

Answer 16

• adapts to whatever circumstances it is presented with and acts against specific threats.
• When we’re exposed to a virus, this immunity acts against it, and develops a “memory” of that virus so that it can be dealt with more quickly upon later exposure

Question 17

Natural Immunity

Answer 17

• happens when exposure to a pathogen happens accidentally, simply through the course of one’s life

Question 18

Natural Active Immunity + Ex.

Answer 18

• is acquired through accidental exposure to a disease agent

- When a child is exposed to measles, their adaptive immune system responds, and they develop resistance to the disease

Question 19

Natural Passive Immunity + Ex.

Answer 19

• is acquired through the immunological experience of someone else
• immunity can be passed on to a foetus from its mother

Question 20

Artificial Immunity

Answer 20

• happens when exposure to a pathogen happens on purpose

Question 21

Artificial Active Immunity + Ex.

Answer 21

• is acquired through deliberate exposure to a disease agent
• when a child is given the measles vaccine, their adaptive immune system responds, and they develop resistance to the disease

Question 22

Artificial Passive Immunity + Ex.

Answer 22

• is acquired through the immunological experience of someone else
• one who has had a disease will develop antibodies to that disease. Their antibodies can be given to someone else, lending an assist to the recipient’s immune system.

Question 23

Cytokines

Answer 23

• are the communication molecules

- used to coordinate the responses of innate and adaptive immunity

Question 24

Antibodies

Answer 24

• have combining sites that attach to specific shapes on pathogens
• produce humoral immunity through the formation of antigen-antibody complexes
• can render pathogens unable to interact with human cells, neutralize toxins, or even agglutinate (clump together) foreign cells

Question 25

Complement Proteins

Answer 25

• activated by antibody-antigen complexes.
• They “drill” holes in foreign cells, allowing them to fill with water until the cells rupture, rendering them innocuous
• have the ability to attract immune cells to the site of infection, marking pathogens for destruction by those cells

Question 26

Phagocytes + Ex.

Answer 26

• are the “eating cells” of the immune system; they can leave the bloodstream and move into tissues in order to encounter and destroy pathogens
• Ex. neutrophils, monocytes, macrophages, and dendritic cells

Question 27

Lymphocytes

Answer 27

• are found throughout the body, but they exist in higher concentrations in lymph nodes and other lymphoid tissues
• Ex. Natural Killer (NK) cells, B cells, and T cells

Question 28

Natural Killer Cells (NK)

Answer 28

• cells do not need any prior exposure to pathogen
• can engage with and destroy any cells identified as a threat
• have the capacity to differentiate between “self” and “not self”

Question 29

B cells + 2 Types

Answer 29

• originate in bone marrow
• When they encounter an antigen that activates them, they rapidly reproduce, leading to a proliferation of clone cells
  2 Types
• Plasma Cells - are antibody factories
• Memory Cells - act as a reserve that can become plasma cells upon activation at a later date

Question 30

T Cells + 3 Types

Answer 30

• originate in the thymus
• they become activated when they encounter a pathogen with that shape, and rapidly divide, forming clones
• the cells themselves provide the immune response rather than as a result of the production of something like antibodies
  3 Types
• Cytotoxin T Cells
• Helper T Cells
• Regulatory T Cells

Question 31

Cytotoxin T Cells, Helper T Cells and Regulatory T Cells

Answer 31

• C = also called killer t cells, poison pathogens or other abnormal cells
• H = use chemicals to communicate. They can attract macrophages to phagocytize threatening cells, and they can activate B cells
• R = shut down the immune response when the job is done, which helps to prevent an immune system overreaction that could potentially damage healthy cells

Question 32

Immune System Hypersensitivity + 3 Forms

Answer 32

• involves an excessive or inappropriate immune respons
  1. Allergy
  2. Autoimmunity
  3. Alloimmunity

Question 33

Allergy

Answer 33

• response to things that are basically harmless

- an extreme allergic reaction can cause anaphylactic shock

Question 34

Autoimmunity

Answer 34

• involves the immune system failing to differentiate between “self” and “not-self.”
• can cause chronic inflammation and destruction of healthy cells and tissues, leading to loss of normal function

Question 35

Alloimmunity

Answer 35

• an immune system overreaction to antigens of another person
• can happen during pregnancy or receiving organ transplants