Gizmono
NASA reignited our hopes of finding alien life when it announced the first direct evidence of liquid water on Mars. But before we start indulging in fantasies of space crabs and reptilian beings, we ought to remember that Mars is a frigid world with a thin atmosphere. And that raises an obvious question: What sorts of life forms could actually live there?
Any life on Mars today is almost certainly microbial, but beyond that, we can’t be sure of anything until we actually dig it up and study it. Still, we can make some educated guesses about the nature of Martian life, by taking a deep dive into some of the weirdest biology on planet
<span>characteristics of skeletal muscle:</span><span>
contains nerve endings; is a voluntary muscle; striped/striated, multi-nucleated (has many nuclei); attached to the bones of the skeleton</span>
Answer:
E. All of the above
Explanation:
In cardiac contractile cells there is rapid depolarization, then a plateau phase and repolarization.
when an action potential stimulates the cell, voltage-gated channels open quickly commencing the positive-feedback mechanism of depolarization. This in turn raises the membrane potential to approximately +30 mV, and this closes the sodium channels. Next comes the plateau phase, where membrane potential declines relatively slowly due to the opening of the slow Ca2+ channels, allowing Ca2+ to enter the cell while few K+ channels are open, leading to K+ to exit. Once the membrane potential reaches approximately zero, the Ca2+ channels close and K+ channels open, allowing the exit of K+. The repolarization lasts approximately for a while and here is when the membrane potential drops until it reaches resting levels once more and repeats the cycle.
Answer:
Eukariotic cells are bigger and complex than bacteria. The difference between cystoskeleton of eukariotic and bacteria cells is the type of proetein in each one.
Explanation:
The cytoskeleton is composed mainly in arrays of protein filaments. Its function is to maintain the shape of the cell, maintain in place the organelles (such as mitochondria, nucleus, etc.) and the transport throughout the cell. Every cell has a cytoskeleton, eukaryotic, bacteria and archaea. Eukaryotic cells are bigger than bacteria and have more organelles in them to maintain in place, this is why cytoskeleton are bigger and complex. The bacteria are a single cell, simpler, with a few organelles, the cytoskeleton is more simple but important. The cytoskeleton is similar in both, the difference is the type of proteins in them. In bacteria are simple proteins, meanwhile, in eukaryotic are a complex protein.
