Answer:
D) the arrangement of the nucleotides within genes
Explanation:
De-oxy ribo nucleic acid that is basically a polymer of nucleotides. Nucleotides are composed of three basic units: a de-oxyribose sugar unit, a phosphate group and nitrogenous bases that can be Adenine, Gunanine, Thymine and Cytosine.Adenine always pairs with Thymine and Guanine always pairs with Cytosine.
This is a universal composition of DNA in each and every living organism. The genes are a segment of DNA that contain specific sequence of nucleotides and encode for a specific trait of organism such as height, weight, eye color etc. The sequence of nucleotides expresses the trait in the form of protein product during the process of Translation. The products of translation are amino acids and every amino acids encode for a specific protein in almost all living organisms.
So, what differs in the specie is the sequence of nucleotides in genes. Infact this is the nucleotide sequence which brings evolution in organism and organisms evolve to form new specie with the passage of time. One major cause of change in nucleotide sequence is mutations due to which the organisms change with time.
Suppose the sequence of nucleotide of specific gene in organism A is
AAGGGGAAATTT
However in other specie organism B of same specie is:
TAGGGGAAATTT
This means only mutation of one base changed the gene in organism B and also its product called protein.
Hope it help!
Era is used to mark the boundaries of geological time scale by using radio carbon dating technique.
Explanation:
Geological time starts with Precambrian time.
Geologically, time is divided between the Precambrian era and present time into era.
The three eras are Paleozoic era, Triassic period and Cenozoic era.
Era is further divided into periods.
Scientists use radio carbon dating to study fossils and rock formation. With this study they were able to divide them in exact geological scale.
Geologic scale is the record of events in earth's history and evolution.
When they compare they can see the difference and similarities to get to the end result
As electrons move along the chain, hydrogen ion are pumped from the stroma of the chloroplast into thylakoid lumen. these leads to creation of proton gradient in thylakoid lumen with the potential energy that will be used to synthesize ATP by enzyme ATPase in the process referred to as rotational catalysis. both chloroplast and mitochondria use electron transport chain to pump protons across the membrane and both enzyme ATPase to produce ATP using proton gradient created in the process of transport of hydrogen ions. the main existing between the electron transport chains of chloroplast and mitochondria is the initial source of energy. chloroplasts obtain their energy from sunlight whereas mitochondria obtain theirs from organic molecules.