Answer:
Early land animals had both lungs AND gills, and their bodies consisted of few hard parts. Meaning they lacked things like an exoskeleton for instance. Animals today have either lungs OR gills and many have protecting hard parts of their bodies.
Explanation:
DNA is necessary for the production of proteins as well as the regulation, metabolism, and reproduction of the cell.
Proteins help repair and build your body's tissues, coordinate bodily functions, and allow metabolic reactions to take place.
Structural, storage, hormonal, enzyme, etc.
Enzymes speed up the rate of a chemical reaction to help support life.
Lipases, amylase, lactase, deoxyribonuclease, etc.
If the outer energy level of the atom is , it does not react readily with other atoms.
The atom has it's outer energy level FULL, it doesn't need anymore electrons; so it's not going to bond with any atoms. It needs no more valence electrons to fill its outermost shell.
Answer: To tell how the environment was years ago and what kind of animals were able to live there. Hope this helps.
Explanation:
