Answer:when you need to replace cells that are old lost or broken
Explanation:
Do u have answer choices with this question?
Answer: The correct answer for the first question is- B) Mechanical.
Adaptation can be described as a process of change in an organism over time that facilitates its survival in the changing environmental conditions. It results due to mutation or genetic change in the individual that gives a benefit to the organism. It exhibits change in structure ( like succulent plants in desert), function, or behavior.
Mechanical is not a type of adaptation as it deals with movement of objects.
The correct answer for second question is- C) Variations.
Variation among organisms in a population results from change in the genetic material or their genetic sequences. Change at the genetic level is thus reflected in the phenotypes ( like different color of feathers in birds).
Thus, difference is in the feather color reflects variations.
Answer:
An ATOM!, is the smallest unit of matter that has characteristic properties of its element. Explanation: An atom a major part of the matter. (Everything in the world (except energy) is made of a material, and, so, everything in the universe is composed of atoms.