Related Concept Videos

Transcellular Transport of Solutes01:23

Transcellular Transport of Solutes

Transcellular transport of solutes is the movement of substances like monosaccharides and amino acids through polarized cells. This transport mechanism is primarily seen in epithelial and endothelial cells aided by membrane transport proteins such as channels and transporters. The tight junctions between these cells confine the membrane proteins to the two sides of the cell. The epithelial cells have distinct apical and basolateral domains. In contrast, the endothelial cells show the luminal...
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Mechanisms of Drug Absorption: Paracellular, Transcellular, and Vesicular Transport01:23

Mechanisms of Drug Absorption: Paracellular, Transcellular, and Vesicular Transport

Drugs need to permeate cell membranes to reach their target sites after administration. Orally administered drugs must transcend intestinal epithelial membrane barriers to infiltrate the systemic circulation. Drugs with a molecular weight of less than 500 Daltons diffuse through gaps between neighboring cells, called paracellular pathways.
However, most drugs use the transcellular route, traversing directly through the cell membranes via two mechanisms: passive and active transport. Passive...
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Transfer RNA Synthesis02:36

Transfer RNA Synthesis

One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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Maximum Power Transfer01:16

Maximum Power Transfer

Numerous practical applications within engineering disciplines, such as telecommunications, necessitate optimizing power delivery to a connected load. This pursuit, however, entails inherent internal losses, which can either equal or exceed the power supplied to the load. The Thevenin equivalent circuit is helpful in finding the maximum power a linear circuit can deliver to a load. It is assumed in this context that the load resistance can be adjusted.
By substituting the entire circuit with...
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