Fro the answer to the question above,
<span>Based on fossil evidence, eukaryotes evolved about <u>2.1 billion</u> years ago</span>.
<span>Approximately the first single-celled Eukaryotes appeared 2.1billion years</span>.
But the multicellular eukaryotes first appeared at 1.5 billion years ago.
I hope this helps
Answer:
1) c. five
2) a. lysine and arginine
3) g. two
4) d. four
Explanation:
A nucleotide can be defined as an organic molecule which forms the building block of nucleic acid such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Basically, nucleotide comprises of the following parts;
1. Nitrogenous base: this includes adenine (A), thymine (T), guanine (G), and cytosine (C) which are mainly found in the DNA while adenine (A), guanine (G), uracil (U) and cytosine (C) are found in the RNA.
2. A phosphate group.
3. A penrose sugar: it is either deoxyribose in DNA or ribose in RNA.
The two parts or chemical components of a nucleotide which do not change throughout the structure of DNA are;
I. Five-Carbon Sugar also known as deoxyribose and it has hydrogen on its second carbon.
II. Phosphate: this is the structural backbone that provides support to DNA.
Histones are a group of highly basic proteins that are mainly associated with deoxyribonucleic acid (DNA) in the nucleus of a living organism and then condense it to chromatin.
Histones include five main classes of relatively small basic proteins containing relatively large amounts of lysine and arginine. Nucleosomes are made of two each of four types of histones.
