On the basis of the principle of complementary base pairing, you would expect the percentage of Purines in an individual's DNA to be equal to the percentage of Pyrimidines.
<h2>Further Explanation: </h2><h3>DNA </h3>
- DNA is a nuclei acid that is responsible for carrying genetic information in living organisms.
- It is through DNA that genetic information is passed from one organism to another through the process of DNA replication.
- Additionally, it carries the information that is used to make proteins which performs various functions in living cells.
- Each Nucleotide in DNA contains a nitrogenous base, a deoxyribose sugar, and a phosphate group.
- DNA molecules are made up of nitrogenous bases; Adenine, Guanine, Cytosine and Thymine.
<h3>Base pairing </h3>
- A DNA molecule exists as a double helix with two strands that are formed as a result of pairing between complimentary bases on the two strands.
- Purine bases bonds to complementary pyrimidine bases. This happens because the shapes of purine and pyrimidine bases allow hydrogen bonds to form between the two.
<h3>Chargaff's rule </h3>
- According to Chargaff's rule the DNA of any cell or organism must have a ratio of 1:1 between purine bases and pyrimidine bases such that the amount of guanine is equal to the amount cytosine, and that the amount of adenine is equal to the amount of thymine.
- According to the rule rule states that adenine pairs only with thymine and guanine pairs only with cytosine.
- Two hydrogen bonds form between an adenine and thymine base pair, whereas three hydrogen bonds form between a guanine and cytosine base pair.
Keywords: Nucleic acids, DNA, nitrogenous bases, Base pairing, Chargaff's rule.
<h3>Learn more about: </h3>
Level: High school
Subject; Biology
Topic; Nucleic acids
Sub-topic: RNA and DNA structure
Answer:
A. True
Explanation:
Surface of the skin contain hundreds of normal flora containing:
1) Staphylococcus aureus
2) Staphylococcus epidermidis
3) Corynebacterium (diphtheroids)
4) Streptococci
5) Pseudomonas aeruginosa
6) Propionibacterium
7)Candida albicans.
So swabbing the surface of the skin anywhere in the body, or culturing the sample in the lab is likely to result in growth of millions of bacterial cells on the culture plate even if we practice good hygiene because of the presence of numerous microbes on the skin being the normal flora.
Stimulated by the action of the ions on its receptors, the pump transports them in opposite directions against their concentration gradients. ... The sodium-potassium pump carries out a form of active transport—that is, its pumping of ions against their gradients requires the addition of energy from an outside source.
D would be the correct statement