B. New substances are formed. In a chemical reaction, the starting molecule must be changed or turn into another. For example: rusts that form in a tin can is a chemical reaction. The iron in the can combines with the oxygen in the atmosphere, creating rust (iron oxide), which is a different substance.
Answer:
about 5 billion years ago
Explanation:
Our solar system formed about 5 billion years a go from a dense cloud of interstellar gas and dust.
Active transport means the molecules move against a concentration gradient from areas of lower concentration to areas of higher concentration.
Meristematic tissue have the ability to
divide themselves. It is the primary site for cell division and cell
differentiation. It produces the new cells and are called growing tissue in
plants. The new cells may or may not divide. It is the source of the regenerative
potential of the plant.
<span>
Cancerous cells can originate anywhere in the
body and can spread into or invade adjoining tissues. It keeps growing and dividing
relentlessly to form lumps. It can also break off and travel to distant
tissues. Cancer cells rejects signals from other cells.</span>
