Answer:
an element is a pure substance which can not be spilt into simpler substances by chemical means
Explanation:
examples hydrogen, oxygen, copper
Each nitrogenous base has one counterpart. The purines are adenine and guanine and they pair with the pyrimidines thymine and cytosine, respectively. There are two hydrogen bonds between adenine and thymine and three hydrogen bonds between guanine and cytosine.
<h2>The given statement is true</h2>
Explanation:
The recent finding of the fossils which showed that <em>Homo erectus</em> and <em>Homo habilis</em> lived side by side in eastern Africa for perhaps half a million years challenged the conventional way that these two species evolved one after the other(<em>H.habilis</em> 1.44 million years old and <em>H.erectus </em>1.55 million years old)
- The fossils were found in Kenya and took years to prepare the specimens for study and to be sure of the identification of the species, the scientists said
- University of Utah geologists determined the dates of the fossils from volcanic ash deposits
- The most recent <em>Homo habilis</em> that had been known was about the same age as the earliest <em>Homo erectus</em><em>,</em> said Daniel Lieberman, a professor of biological anthropology at Harvard University, “Now we have extended the duration of the habilis species, and there’s no doubt that it overlaps considerably with erectus”
- The fact that the two hominid species lived together in the same lake basin for so long and remained separate species, Meave Leakey said in a statement from Nairobi, “suggests that they had their own ecological niche, thus avoiding direct competition”
Answer:
This promotes the repair response of diseased tissue using stem cells.
Explanation:
It also uses stems instead of donor organs.
I gave you two, hope it helps.
