The answer to the question stated above is letter b. <span> <span>a meteor or asteroid colliding with Earth
</span></span> <span>The mass extinction at the end of the Mesozoic Era was caused by </span>a meteor or asteroid colliding with Earth. This was said to happen about 65 million years ago.
Answer:
Eukaryotic ATP production usually takes place in the mitochondria of the cell.
Explanation:
This ATP production by the mitochondria is done by the process of respiration, which in essence is the use of oxygen in a process which generates energy. Most of the ATP of a eukaryotic organism is made in the mitochondria during the last phase of cellular respiration that is called the electron transport chain (ETC). A mitochondrion is an organelle within a eukaryotic cell.
DNA I’m not sure if im right sorry if im wrong
Answer:
See attached image
Explanation:
Action potential can be split into 5 phases (0-4), where phase 4 leads from one action potential to the next. Phase 0 is the line up and is known as depolarization, it is here where the action potential is triggered and fast Na channels will open. Next, is phase 1 called early repolarization which is the little bit at the beginning of the plateau-here the Na channels will close. Then you have the plateau phase where Ca channels are open at the beginning and close at the end. Then is phase 3 called repolarization which is the big slope down and here is where the normal transmembrane ionic concentration gradients are restored. Finally, phase 4 which is the resting phase occurs. There are many resources online if you need more details, here is a pretty good one: http://www.pathophys.org/physiology-of-cardiac-conduction-and-contractility/