For plants and other organisms to develop differences among their respective species the alleles of their genes must contain
variations. what is the original source of these variations?

What is an endocrine function? (apex) a. esophageal glands release mucus into the esophagus b. salivary glands release saliva into mouth c. swear glands release sweat to the skin d. the pineal gland releases melatonin into the bloodstream

Where can a dna be found in a prokaryotic cell

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?