Lecture 6 : Lymphatic System

Question 4

What is the Lymphatic System?

Answer 4

A network of vessels and tissues that assist in circulating fluids and the immune response

Closely associated with the cardiovascular system

Question 5

What fluid is transported back into the bloodstream by the lymphatic system?

Answer 5

Lymph

Question 6

What role does the lymphatic system play in defending the body?

Answer 6

Helps defend the body against diseases

Question 7

What happens to tissue fluid before it returns to the bloodstream?

Answer 7

It passes through lymph nodes for pathogen recognition and immune response triggering

Question 8

Where is the lymphatic system not present?

Answer 8

CNS or bone marrow

Question 9

What substances does the lymphatic system help transport?

Answer 9

Fats and fat-soluble vitamins

Question 10

What drives lymph movement into lymphatic capillaries?

Answer 10

Hydrostatic pressure of tissue fluid

Question 11

What influences the movement of lymph through lymphatic vessels?

Answer 11

• Action of skeletal muscles
• Respiratory movements
• Smooth muscle in larger lymphatic vessels

Question 12

What prevents backflow in lymphatic vessels?

Answer 12

Valves

Question 13

What are the three layers of lymphatic vessels?

Answer 13

• Endothelial lining (inner)
• Smooth muscle (middle)
• Connective tissue (outer)

Question 14

What is chyle?

Answer 14

Cloudy lymph from special lymphatic vessels (lacteals) that allows fat absorption

Question 15

What are lymphatic trunks named for?

Answer 15

The regions they serve e.g. lumbar, intestinal, intercostal

Question 16

What causes the formation of lymph?

Answer 16

Filtration from plasma exceeds reabsorption, leading to net formation of tissue fluid

Question 17

What is oedema?

Answer 17

Accumulation of excess tissue fluid

Question 18

What are lymph nodes primarily composed of?

Answer 18

Lymphocytes and macrophages

Question 19

Where are lymph nodes located?

Answer 19

• Cervical region
• Axillary region
• Supratrochlear region
• Inguinal region
• Pelvic cavity
• Abdominal cavity
• Thoracic cavity

Question 20

What is the largest lymphatic organ?

Answer 20

Spleen

Question 21

What are the two tissue types found in the spleen?

Answer 21

• White pulp (lymphocytes)
• Red pulp (red blood cells, lymphocytes, macrophages)

Question 22

What is the function of the thymus?

Answer 22

Site of T cell maturation and secretes thymosins

Question 23

What are innate defenses?

Answer 23

Barriers, innate cells, and proteins that act immediately to prevent pathogen entry and growth

Question 24

What are adaptive defenses?

Answer 24

T cells and B cells that provide a specific response to pathogens

Question 25

What is the role of phagocytes?

Answer 25

Bind and internalize pathogens before digesting them

Question 26

True or False: Adaptive immunity has a faster response time than innate immunity.

Answer 26

False

Question 27

What triggers inflammation?

Answer 27

Chemical mediators released by innate immune cells when tissues are damaged

Question 28

What is the first adaptive immune response characterized by?

Answer 28

Slower response taking around 5-7 days

Question 29

What happens to T and B cells upon re-exposure to the same pathogen?

Answer 29

They respond faster due to immunological memory

Question 30

What is the function of antibodies?

Answer 30

Bind pathogens and make them more visible to other immune cells

Question 31

Fill in the blank: The primary lymphoid organs are involved in _______ development.

Answer 31

Lymphocyte

Question 32

What is a key characteristic of the inflammatory response?

Answer 32

Vasodilation and increased vascular permeability