The nitrogenous bases form hydrogen bonds between opposing DNA strands to form the rungs of the "twisted ladder" or double helix of DNA or a biological catalyst that is found in the nucleotides. Adenine is always paired with thymine, and guanine is always paired with cytosine. These are known as base pairs.
<u>Answer:</u>
Theory is used to describe a fact that has always been observed true but could at some future time not be observed as true.
Option: (B)
<u>Explanation:</u>
- Hypothesis is a guess that is based upon the observation. Hypothesis is an idea that might occur in future but doesn’t fall in present theory.
- Generally hypothesis is not based upon facts and also they aren’t proved. Interpreting certain fact is theory.
- Theories are only the explanation of something but facts is observable.
- Theory is something like a concept or idea that is observed to be true at present may fail in near future.
- Law is absolute and true. Generally, they are represented by mathematical expression or equation.
- For example, Newton's law, Law of gravity, Law of thermodynamics.
B is the correct answer because all the classes are hierarchy’s in a sense
Answer:
Having a true coelom as a body cavity.
Explanation:
Coelomate contain tissues derived from mesoderm, whereas pseudocoelomates have no such tissue. have a gut that lacks suspension within the body cavity, whereas pseudocoelomates have mesenteries that hold the digestive system in place. Have a body cavity completely lined by mesodermal tissue, whereas pseudocoelomates do not.