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 
.
Answer: B. providing access to objects that are hard to find
Explanation: A specimen can be simply refered to as a sample of blood, tissue, fluid or a piece of a matter which scientist take or obtain to have a better look (study) at it in a lab.
Specimen collection is the process involved in getting or obtaining these samples for better analysis in a lab. This process help scientist get, obtain or have access to samples or objects that are not easily accessible.
Therefore Specimen collection helps scientist carry out experiment by providing access to objects that are hard to find.
Answer:
The correct answer is a acyl-carnitine readily cross the mitochondrial inner membrane but the acyl CoA do not.
Explanation:
Fatty acids are activated to form fatty acyl CoA by the help of ATP and CoA SH.But the so formed Acyl CoA cannot cross or pass the inner mitochondrial membrane to enter the mitochondrial matrix to initiate beta oxidation of fatty acid.
To overcome this problem fatty acyl CoA is converted to acyl carnitine and the so formed acyl carnitine readily crosses the inner mitochondrial membrane and enters the mitochondrial matrix.
Answer:
We will start with a very simple way of showing the arrangement of electrons around an atom. Here, electrons are arranged in energy levels, or shells, around the nucleus of an atom.
Explanation:
