Cell wall because their has to be something protecting it.
The answer is D. The natural selection is a theory which illustrates the gradual process of evolution in the population due to the change of environment. The key point is the mutation (variation) exists in the population before the environment changing. For C, if the environment does not change, though the adaptation is useful to environment, it will not be selected. Because the organisms without the adaptation will not die.
The physical location of a gene within the genome is called the Locus.
Answer:
Every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. ... Use coefficients of products and reactants to balance the number of atoms of an element on both sides of a chemical equation.
Explanation:
Protons and Neutrons affect the mass. Protons and Electrons change the charge of the atom (positively or negatively charged). Valence electrons are the ones that do fun stuff in chemical reactions, they are responsible for making/breaking bonds, at least to my understanding.
Hope this helps.