Answer:
the billions of cells that originate from one parent cell
Explanation:
Number 1: The Circulatory System is a vast network that contains organs and vessels.
number 2: Arteries have a thick wall which helps a powerful pressure from the heart.
number 3: Without the Circulatory System the body wouldn't be unable to maintain a internal environment.
number 4: The Circulatory and Respiratory system both have gas to help a or animal live in there internal environment.
number 5: Blood vessels brings oxygen to the tissues and absorbs carbon dioxide and other waste products to clear the lungs. And with out oxygen the tissues won't absorb carbon dioxide to clear out the lungs.
number 6: D
In plant seeds, the photoreceptor phytochrome is responsible for the process termed photomorphogenesis<span>. This occurs when a seed initially situated in an environment of complete darkness is exposed to light. A brief exposure to electromagnetic radiation, particularly that whose wavelength is within the red and far-red lights, results in the activation of the photorecepter phytochrome within the seed. This in turn sends a signal through the signal transduction pathway into the nucleus, and triggers hundreds of genes responsible for growth and development</span>
Answer:
the symbol for nitrogen is N
Explanation:
