Search results
Results from the WOW.Com Content Network
Many biological circuits produce complex outputs by exploiting one or more feedback loops. In a sequence of biochemical events, feedback would refer to a downstream element in the sequence (B in the adjacent image) affecting some upstream component (A in the adjacent image) to affect its own production or activation (output) in the future.
One of its murburn products (CO 2) is a voidable gas and the other product (water, H 2 O) is also the solvent. Owing to colligative effects, the latter is spontaneously mobilized to move out, thereby retaining cellular composition in a dynamic fashion. Physically, these processes also generate heat and turgor.
This keeps the reentry heat from getting inside the capsule. Capsules see a more intense heating regime than spaceplanes and ceramics such as used on the Space Shuttle are usually less suitable, and all capsules have used ablation. In practice, capsules do create a significant and useful amount of lift.
Respiration is one of the key ways a cell releases chemical energy to fuel cellular activity. The overall reaction occurs in a series of biochemical steps, some of which are redox reactions. Although cellular respiration is technically a combustion reaction , it is an unusual one because of the slow, controlled release of energy from the series ...
After a cell has been depolarized, it undergoes one final change in internal charge. Following depolarization, the voltage-gated sodium ion channels that had been open while the cell was undergoing depolarization close again. The increased positive charge within the cell now causes the potassium channels to open.
The cell membrane of CaCl 2-treated cells is severely depolarized during the heat shock stage, and as a result, the drop in membrane potential reduces the negative nature of the cell's internal potential, allowing negatively charged DNA to flow into the interior of the cell. Afterwards, the membrane potential can be raised back to its initial ...
Structure of the human uncoupling protein UCP1. An uncoupling protein (UCP) is a mitochondrial inner membrane protein that is a regulated proton channel or transporter.An uncoupling protein is thus capable of dissipating the proton gradient generated by NADH-powered pumping of protons from the mitochondrial matrix to the mitochondrial intermembrane space.
The cycle does generate heat, and may be used to maintain thermal homeostasis, for example in the brown adipose tissue of young mammals, or to generate heat rapidly, for example in insect flight muscles and in hibernating animals during periodical arousal from torpor. It has been reported that the glucose metabolism substrate cycle is not a ...