Explain the role of active transport in the living organism. Identify a similarity and difference between facilitated transport and active transport. What is the difference between active and passive transport? Do living systems, like the human body, use one or both? Provide examples Defin...
The maternal dose of cimetidine ingested by a suckling infant based on body weight was estimated to be 6.7%, which appears to be safe under normal conditions. This study provides the first definitive evidence of an active transport system for drug transfer into human milk, which may have ...
Active school transport (AST) may increase the time that children spend in physical activity (PA). This study examined relationships between AST and weekday moderate-to-vigorous physical activity (MVPA), light physical activity (LPA), sedentary time (SED) and total activity during naturally organiz...
Active transport mechanisms require the use of the cell’s energy, usually in the form of adenosine triphosphate (ATP). If a substance must move into the cell against its concentration gradient, that is, if the concentration of the substance inside the cell must be greater than its concentratio...
reverse cholesterol transport transintestinal cholesterol transport bile salt biliary cholesterol Introduction The reverse cholesterol transport (RCT) pathway is a crucial antiatherogenic mechanism which mediates the removal of cholesterol from body tissues into feces (Glomset, 1968). The mechanism by which...
This chapter discusses the role of pumps and exchangers in active transport. Movement of ions across cell membranes involves a change in the free energy that depends on the concentration of the ion on both sides of the membrane, the charge on the ion, and the membrane potential. At rest in...
In active matter systems, individual constituents convert energy into non-conservative forces or motion at the microscale, leading to morphological features and transport properties that do not occur in equilibrium and that are robust against certain perturbations. In recent years, a fruitful method for...
paracellular drug transport across the BBB and contribute to the high transendothelial resistance (TEER) that limits the passive diffusion of external compounds between the brain and blood [8,9]. Both pericytes and astrocytes play a supporting role in maintaining the structure and function of the ...
In addition, it is a type of physical activity which benefits public health. Several health experts recommend at least 30 min of daily physical activities, and some research showed the benefits of daily walking (e.g., walking to public transport stations) for achieving this goal (Besser and...
Here, frictional damping dominates viscous dissipation of the momentum and, therefore, the active forcing is balanced by the friction. Under these conditions, the nematic approaches the so-called ‘dry’ limit, where there is no long-range transport of momentum19,63. Although the continuum ...