Concept explainers
Introduction:
The lymphatic system is the drainage system of the body that picks up the lymph (excess interstitial fluid) and returns it to the blood. The lymph capillaries absorb the excess and leaked fluid and weave between the blood capillaries as well as the tissue cells.
Answer to Problem 1MC
Correct answer:
The lymph capillaries contain endothelial cells, which are separated via flap like valves that can open wide.
Explanation of Solution
Explanation for the correct answer:
Option (c) is given that lymph capillaries possess endothelial cells separated by flap like valves that can open wide. The lymph capillaries contain the flap like mini valves, which act as the one-way swinging door. The endothelial cells that form the walls overlap one another loosely thus, forming the valve. Hence, option (c) is correct.
Explanation for incorrect answers:
Option (a) is given that lymph capillaries are open-ended same as the drinking straws. The lymph capillaries are not open at one end; instead, they are separated by the flap-like minivalves, which act as one way swinging door. So, it is an incorrect option.
Option (b) is given that lymph capillaries have continuous tight junctions like the capillaries present in the brain. The lymph capillaries possess flap like minivalves and not the tight junctions. So, it is an incorrect option.
Option (d) is given that lymph capillaries contain special barriers that stop cancer cells from entering. The bacteria and the cancer cells can enter the lymph capillaries as they do not contain special barriers to prevent their passage. So, it is an incorrect option.
Hence, options (a), (b), and (d) are incorrect.
The lymph capillaries contain endothelial cells that form their wall. The endothelial cells overlap at the edges and form flap like mini valves that functions as one-way door.
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Chapter 12 Solutions
Essentials of Human Anatomy and Physiology (Custom)
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