Lymphatic System

Question 1

Lymphatic System

Answer 1

Responsible for the exchange of substances between the blood and the interstitial fluid that bathes the cells
Takes place across the thin walls of the capillary beds
Transports fats from digestive system to circulatory system

Question 2

As blood proceeds along the capillaries:

Answer 2

1. Blood pressure drops
2. Capillary becomes hypertonic compared to surrouding tissue fluids
3. The resulting osmotic gradient pulls water into the capillary by osmosis near the venule end

Question 3

How fluid enters the system:

Answer 3

By diffusing into tiny lymph capillaries intermingled among capillaries of the cardiovascular system
Eventually drains into the circulatory system near the subclavian veins

Question 4

Lymph

Answer 4

Fluid inside the lymphatic system

Question 5

Structure of lymph vessels

Answer 5

Have valves to prevent backflow
Rhythmic contraction of vessel walls to help draw fluid into lymphatic capillaries
Depend mainly on skeletal fluid to squeeze fluid towards the heart

Question 6

Lymph Nodes

Answer 6

Where lymph is filtered and lymphocytes are formed
Inside is a “honeycomb” of connective tissue filled with leukocytes called lymphocytes and macrophages
When body is fighting bacteria, lymph nodes swell

Question 7

Lymphocytes and Macrophages

Answer 7

Specialized for attacking viruses and bacteria

When the body is fighting bacteria these cells multiply

Question 8

RBC

Answer 8

Biconcave due to the absence of nucleus
Lifespan: 120 days
Dead RBC recycled into bile
Also called erythrocytes

Question 9

Hemoglobin

Answer 9

Protein attached to RBC
4 Polypeptide chains
Each group has an iron chain that binds to oxygen
One erythrocyte carries 8 oxygens