3.8 billion – 2.5 billion years ago
The Archean is the name of the age which started with the shaping Earth. This time of Earth's history endured quite a while, over 2.5 billion years. When the archean age ended the earth was just coming alive.
Answer: Amino acids are organic compounds (molecules) that contain amine (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid.
Explanation: The variation seen in naturally occurring amino acids arises from differences in this side chain.
Answer : An atom with 7 protons, 6 neutrons,
and 7 electrons has an atomic mass of 13 amu.
Explanation:
As we are give that,
Number of protons
7
Number of electrons =7
Number of neutrons =6
As we know that,
Atomic number =Number of protons = Number
of electrons =7
Atomic mass = Number of neutrons + Atomic
number
Atomic mass = 6 + 7 = 13 amu
Therefore, the atomic mass is, 13 amu
Cell division starts with one parent cell and finishes with two cells. Each daughter cell has the same DNA as the parent cell
