What is different about the capillary exchanges seen in a with fenestrations and intercellular clefts lacking those modifications?

Capillary exchanges seen in a capillary with fenestrations and intercellular clefts

* Fenestrations: These are small pores in the capillary wall that allow for the passage of small molecules, such as water, ions, and small proteins. Fenestrations are found in capillaries in the renal glomerulus, the intestinal mucosa, and the choroid plexus of the brain.

* Intercellular clefts: These are small gaps between the endothelial cells that line the capillary wall. Intercellular clefts are found in capillaries in the liver, the spleen, and the bone marrow.

Capillary exchanges seen in a capillary lacking fenestrations and intercellular clefts

* Tight junctions: These are specialized junctions between endothelial cells that prevent the passage of molecules between the cells. Tight junctions are found in capillaries in the brain, the heart, and the skeletal muscle.

The different types of capillary modifications allow for the passage of different types of molecules into and out of the capillaries. Fenestrations and intercellular clefts allow for the passage of small molecules, while tight junctions prevent the passage of most molecules. This allows capillaries to regulate the exchange of molecules between the blood and the surrounding tissues.