Answer:
<u>A. 460°C</u>
or about 900 degrees fahrenheit
Answer:
1. Potassium
2. increasing towards zero
3. hyperpolarization
4. voltage-regulated Potassium
Explanation:
Membrane potential can be defined as the difference in electric charges inside and outside of a cell. The resting membrane potential (RMP) occurs when there is no net current across the membrane and therefore the cell is in a non-excited state. At the RMP, sodium ions (Na+) are more concentrated inside the extracellular fluid (ECF) than inside the intracellular fluid (ICF), while potassium ions (K+) are more concentrated inside the ICF. The diffusion of K+ outside the cell triggers its hyperpolarization, by becoming the membrane potential more negative compared to the resting potential. As the potential nears +35 mV, the voltage-regulated potassium channels are open, thereby K+ ions leave the cell down its concentration gradient, while voltage-gated Na+ channels become saturated and inactivate.
The best answer is D.
In active transport, molecules move against a concentration gradient from areas of lower concentration to areas of higher concentration. This happens a lot in neurons. The membrane proteins are constantly pumping ions in and out to get the membrane of the neuron ready to transmit electrical impulses.
In active transport , energy is required to move molecules across the cell membrane. Carrier proteins are needed for this e.g. proteins of the GLUT family which transport glucose molecules across the cell membrane. Carrier proteins are very specific. GLUT proteins will only move glucose molecules and not sodium or calcium. There are hundreds of types of carrier proteins.
