Gases in Earth's Atmosphere. Nitrogen and Oxygen are by far the most common. Dry air is composed of about 78% Nitrogen (N2) and about 21% Oxygen (O2). Argon, Carbon Dioxide (CO2), and many other gases are also present in much lower amounts; each makes up less than 1% of the atmosphere's mixture of gases.
So therefore Oxygen is the gas that makes up the largest portion of the Earths Atmosphere.
Nitrogenous base DNA consists of four unique nucleotides that each contain one unique nitrogenous base—adenine (A), thymine (T), cytosine (C), or guanine (G).
The specific arrangement of these four bases within the DNA of each organism gives that organism its unique traits; here are the arrangements:
-<u>Adenine</u> is paired with <u>Thymine</u> (think of A for apple and T for tree)
-<u>Cytosine</u> is paired with <u>Guanine</u> (think of C for car and G for garage)
search "DNA base pairs" and go to images for better understanding
Answer:
DNA replication is described as semi-conservative.
Explanation:
DNA replication is described as semi-conservative because each double helix formed comprises one strand from the helix from which it was copied and a new strand. That is, the replication of one helix results into two new copies of which each contains one of the original double stranded helix from which it was synthesized.
B. Hydrogen Bonds connect nitrogenous bases together
Answer:
True
Explanation:
It is correct to say that the deeper in the ground we go, the older things get. This statement is specifically valid in a terrain that has not been disturbed by tectonic activities.
<em>According to the law of superposition of strata "in a sequence of sediment, the oldest layer is usually at the bottom and the youngest is on top provided the area is undisturbed". </em>
Based on this law of superposition of strata, it clearly seen that the deeper we go down in the earth, the older things get.
