Answer:
i have a pusheen popsocket
Explanation:
i dunno i like pusheen and wanted to answer lol
Answer:
Cross-bridges would form in the absence of an action potential from a motor neuron.
Explanation:
The injected calcium ions would bind to troponin. Troponin would make tropomyosin move away from the myosin-binding sites on actin. The presence of free binding sites on the actin would be followed by the contraction cycle. This would include hydrolysis of ATP to energize myosin heads and binding of these heads to actin to form cross-bridges. Therefore, cross-bridge formation would occur without any action potential if calcium ions are injected directly into the muscle.
Answer:
The right answer is (B) the extracted lipids cover twice the surface area of the intact red blood cells.
Explanation:
To explain this statement is necessary to take into consideration the structure of a lipid. On the first place lipids that form membranes are called phospholipids, this means they have one 'head' that is hydrophilic and a tail composed by the lipidic chain that is hydrophobic.
In a biologic context, the phospholipids form the cellular membrane. They do so by a bi-layer disposition, meaning that one the external side of the cell there is a layer of phospholipids with the hydrophilic head and in the internal side, there is a second layer of phospholipids with the hydrophilic head. The hydrophobic 'tails' are in the middle. This disposition is due to the fact that both the external and the internal environments are water based.
Therefore, since each cell has a bilayer membrane of phospholipids, when the cells are dissolved and all the lipids that used to form the membrane are put together, they will occupy twice the surface of the red blood cells.
