Billions of years ago Earth was just a planet made out of rocks. After the Big Bang Theory, Earth was being formed. After it was formed it took years and years for life to even start on earth. What started life was when Earth started to produce it's own water then soon it made volcanoes which made islands which formed into gigantic places that we call home. Later on Earth started to produce it's own weather and atmosphere. As earth had it's first rainfall, the ground started to grow green leaves that we call grass and trees. With those changes, life was starting to be born. The first living things on Earth, singled-celled micro-organisms or microbes lacking a cell nucleus or cell membrane known as prokarotes. Later on the the organisms starting producing more organism which evolved later into human and animal life.
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Answer:
ANS - Autonomic Nervous system.
Explanation:
Autonomic nervous system (ANS) is responsible for regulating the involuntary control of smooth, heart muscles and some glands and organs.
Whereas the somatic nervous system (SNS) regulates the voluntary contraction of the skeletal muscles.
It would eventually go extinct. If you put a shark in a fresh water pond and it can't adapt to fresh water it will die.
Answer:
The question is incomplete.
However, I notice that your question is mainly dealing with
"Nucleotides with a single ring structure"
I tackled that part, also providing explanation to the point you focused on.
Explanation:
Nucleotides are compounds in which nitrogenous bases (purines and pyrimidines) are conjugated to the pentose sugars (ribose or deoxyribose) and at least one phosphate group. Thus a nucleotide consists of a nitrogenous base, pentose sugar and at least one phosphate group.
Examples of the nitrogenous bases are Adenine, Guanine, Thymine, Uracil and Cytosine. Of all, Thymine, Uracil and Cytosine are with single ring, while Adenine and Guanine are double ring structure.