Sec 30.6: Lymphatic System

Question 1

What does the lymphatic system consist of?

Answer 1

It consists of a complex network of organs, vessels, and nodes throughout the body

Question 2

What does the lymphatic system do?

Answer 2

It collects excess fluid that leaks out of the blood capillaries into the area between the cells

Question 3

What is interstitial fluid?

Answer 3

It is the excess fluid that brings nutrients to the cells and removes their wastes

Question 4

What happens to interstitial fluid?

Answer 4

90% of it returns to the capillaries, but 3 liters per day remain outside blood vessels

Question 5

What would happen to the body without the lymphatic system?

Answer 5

The body would begin to swell as more fluid is trapped in tissues

Question 6

How is swelling prevented?

Answer 6

The lymphatic system prevents this by collecting fluid and filtering it to remove dead cells and microorganisms, then returning the cleaned fluid to the circulatory system

Question 7

When does the lymphatic circulation begin?

Answer 7

It begins when the fluid between the cells enters the lymphatic capillaries, where it becomes known as lymph.

Question 8

What happens after lymph enters the lymphatic capillaries?

Answer 8

Lymph flows into larger vessels where it relies on contractions of skeletal and smooth muscles to circulate. One-way valves in these vessels prevent the lymph from flowing backward.

Question 9

What are nodes?

Answer 9

They are small rounded structures where lymph collects from the vessels

Question 10

What is the function of lymph nodes?

Answer 10

They filter the lymph and trap bacteria, viruses, fungi, and cell fragments for specialized immune cells to ingest and destroy.

Question 11

How does lymph return to the circulatory system?

Answer 11

Vessels carry lymph out of nodes. Two large vessels, one on each side of the body, enter veins just under collarbones, where lymph is returned to the blood.

Question 12

What happens if tissues or nodes are damaged or removed?

Answer 12

Lymph is not drained, and the body begins to swell

Question 13

How can swelling be brought down?

Answer 13

Through exercise, pressure bandages, and massages that exert pressure on tissues and nodes to “push” lymph into the vessels

Question 14

What are the 3 structures involved in the lymphatic and immune systems?

Answer 14

Tonsils, thymus, and spleen

Question 15

What are tonsils and where are they located?

Answer 15

They are lymph nodes located in the back of the throat on either side

Question 16

What is the function of tonsils?

Answer 16

They help to filter out bacteria and viruses that have escaped the body’s outer defenses

Question 17

What results in tonsil removal?

Answer 17

Too many pathogens enter the body, so the tonsils become swollen and infected and must be removed

Question 18

Where is the thymus located?

Answer 18

It is located behind the breastbone

Question 19

What is the function of the thymus?

Answer 19

It is important in developing lymphocytes to fight pathogens
- immature lymphocytes migrate from bone marrow to thymus to develop the ability to recognize specific microorganisms
- they leave the thymus and circulate through lymphatic and circulatory systems to protect the body.

Question 20

What is the spleen?

Answer 20

It is the largest organ in the lymphatic system

Question 21

What is the function of the spleen?

Answer 21

It filters and cleans the lymph of cell fragments and abnormal tissue
It also contains many lymphocytes and other white blood cells that destroy bacteria and foreign organisms.