DNA is composed of nucleotides, which are composed of three parts:
1. A five carbon carbohydrate (pentose)
Pentose is classified as a monosaccharide (simple carbohydrate), and its molecular formula is represented by
. They are water soluble molecules with sweet taste. Monosaccharides may have from three carbon atoms (trioses) to six (hexoses). In DNA is present pentose (5 carbon atoms)
2. A nitrogenous base
Nitrogenous bases are ring-shaped compounds that contain nitrogen in their molecular structure. They are classified into two groups: purines and pyrimidines
The purine bases are adenine (A) and guanine (G). They are larger and contain more than one ring in their structure,.
The pyrimidines, cytosine (C), uracil (U) and thymine (T), are smaller and composed of a single ring.
3. One or more phosphate groups
A phosphate consists of a trivalent anion that contains one phosphorus atom and four oxygen atoms. Its molecular formula is expressed by
.
The replication happens during the S phase.
Answer: B)
humans and chimps share a common ancestor.
Explanation:
Answer:
A
Explanation:
It is believed that the moon was formed shortly (relative time) after the earth was newly formed. This occurred in a massive planet-sized collision that ejected a huge chunk of the earth out into space. The chunk, still within earth gravitational reach, began orbiting the earth becoming the moon. Both earth and moon are slightly more than 4 billion years old.