D. The microscope. It is now the workhouse of biology
<h2>
Answer: c. another action potential can be generated provided the stimulus is large enough.</h2>
Explanation:
Refractory period - (1) absolute refractory period and (2) Relative refractory period
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Relative refractory period -It is the interval immediately following the Absolute Refractory period during this period, initiation of a second action potential is inhibited but not impossible. It is the period shortly after the firing of a nerve fiber when partial repolarization has occurred and only a greater than normal stimulus can stimulate a new response.
Answer:
See the answer below
Explanation:
The modern model of the atom sees it as <u>a small structure with a dense, positively charged core called nucleus</u>. The nucleus houses most of the masses of the atom and consists of the proton and the neutron. The positively charged proton is primarily responsible for the positiveness of the nucleus. At some distance away from the nucleus is a light, negatively charged particle called the electron that revolves around the nucleus in an orbit-like fashion .
For a neutral atom, the number of the positively charged proton balances that of the negatively charged electron which circulate rounds the nucleus. Atoms in which these two particles do not balance each other are no longer described as being neutral.
Correct answer: B). They can be transformed into any type of body cell.
The stem cell is the biological cell that has the ability to differentiate into other types of cell. These are always found in the multi-cellular organism. These cells are known to be the foundation of every tissue and organ in our body. Embryonic stem cell is pluripotent, it means they can give rise to every type of cell in the body.
Example: Hematopoietic stem cells that give rise to all type of blood cells like red blood cells, white blood cells etc.
Hence, the correct answer would be option B.
