Exam 3: Lymphatic System

Question 1

Capillary Level

Answer 1

-fluids pushed out of vessels and into tissues

Question 2

Interstitial Fluid

Answer 2

• fluid within tissues

- venules pick up most, but not all of this fluid

Question 3

Lymph

Answer 3

-interstitial fluid picked up by lymphatic system

Question 4

Lymphatic System (consists of)

Answer 4

-consists of lymph vessels and lymphatic tissues and organs

Question 5

Functions of Lymphatic System

Answer 5

• absorbs dietary lipids and fat-soluble vitamins (A, D, E, K)
• returns interstitial fluid back into blood stream (done by lymph vessels)
• initiates an immune response when mecessary (done by lymphatic tissues/organs)

Question 6

Lymph Vessels (system)

Answer 6

-low pressure system

Question 7

Lymphatic Capillaries

Answer 7

• smallest lymph vessel
• wall composed of endothelium (simple squamous)
• walls have 1-way flaps which allow lymph to enter but not escape

Question 8

Lacteals

Answer 8

• lymphatic capillaries in small intestine

- function absorb dietary fats

Question 9

Lymphatic Vessels (characteristics)

Answer 9

• like veins, have 3 tunics
• have valves which prevent backflow
• take lymph to and from lymph nodes

Question 10

Lymphatic Trunks

Answer 10

• formed from merging lymphatic vessels

- drain into lymphatic ducts

Question 11

Lymphatic ducts

Answer 11

• Right Lymphatic Duct

- Thoracic Duct

Question 12

Right Lymphatic Duct

Answer 12

• receives lymph from right side of head, neck and thorax, right upper limb
• drains into right subclavian vein

Question 13

Thoracic Duct

Answer 13

• receives lymph from left side of head, neck, thorax, left upper limb, entire abdomen, left and right lower limbs
• drains into left subclavian vein

Question 14

Lymphedema

Answer 14

• buildup of interstitial fluid due to lymph vessel damage
• causes: surgery that removes lymph vessels (eg for breast cancer), cancer spread, infection from parasitic worms (filarial worms)

Question 15

Pathway of Lymph

Answer 15

-lymphatic capillaries–>lymphatic vessels–>lymphatic trunks–>lymphatic ducts–>venous circulation

Question 16

Lymphatic Cells

Answer 16

-start and produce immune response when exposed to antigens

Question 17

Antigens

Answer 17

-anything perceived as foreign in the body

Question 18

Lymphocytes

Answer 18

• T-lymphocytes (T-cells)

- B-lymphocytes (B-cells)

Question 19

T-Lymphocytes

Answer 19

• mature in thymus
• functions: some of these cells manage/direct an immune response, while others directly attack cells
• general/soldiers

Question 20

B-Lymphocytes

Answer 20

• mature in red bone marrow
• function: many secrete antibodies which attach to antigens and immobilize them until another cell destroys antigen
• handcuffs

Question 21

Macrophages

Answer 21

• monocytes that migrated from bloodstream into other tissues
• function: phagocytize foreign substances

Question 22

Lymphatic Structures

Answer 22

• not organs
• consists of connective tissue containing lots of lymphatic cells
• not surrounded by CT capsule

Question 23

Lymphatic Nodules

Answer 23

• main type of lymphatic structures
• clumps of lymphatic cells within other organs
• ex: tonsils in pharynx, MALT (Mucosa Associated Lymphatic Tissue) in walls of GI and respiratory tract
• both respond to antigens

Question 24

Lymphatic Organs

Answer 24

-lymphatic structures surrounded by connective tissue capsule

Question 25

Thymus

Answer 25

- behind sternum - function: T-lymphocytes mature and differentiate here. this happens prior to adult hood - adult thymus is non functional

Question 26

Lymph Nodes

Answer 26

- tiny oval organs - hundreds - found in clusters - connect with lymphatic vessels - functions: filter lymph, activate immune response if antigens found in lymph - infection: lymph nodes become swollen and tender

Question 27

Cancer Spread and Lymph Nodes

Answer 27

- cancer can spread through lymph vessels and lymph nodes | - cancerous lymph nodes tend to be hard and nontender

Question 28

Spleen

Answer 28

- largest lymphatic organ in body - located in upper left abdomen, behind and lateral to stomach - red pulp and white pulp - functions: does NOT filter lymph, it filters blood

Question 29

Red Pulp

Answer 29

- splenic sinusoids (large capillaries) and splenic cords - contains erythrocytes, platelets and macrophages - function: removes old erythrocytes and platelets - graveyard for erythrocytes

Question 30

White Pulp

Answer 30

- lymphocytes | - will start an immune response if antigens found in blood