Answer:
D
Explanation:
The double helix is a description of the molecular shape of a double-stranded DNA molecule. In 1953, Francis Crick and James Watson first described the molecular structure of DNA, which they called a "double helix," in the journal Nature.
Answer:
Explanation:
Light provides the energy needed for photosynthesis. Increasing the light intensity increases the rate of photosynthesis, provided plenty of carbon dioxide and water are available. ... This states that the intensity of light is inversely proportional to the square of the distance from the source.
A food pyramid is a represntation of predatory relationships in the food chain.
When people used stone tools,
The in-between period of time when the first man appeared and when man developed a writing system. Or the period of time before man became literate.
