The answer is B .
Biotic factor refers to living things .
Question:why were maggots there only after the flies left
Hypotheses:the maggots are fly larva
A variation is a reference to the differences or deviations, such as the structure and form, as for crossing over is the exchange of genetic material between the non-sister chromatids of the homologous chromosomes during meiosis.
Answer:
(1) Red Blood Cell
(2) Enzymes
Explanation:
(1) Oxygenated Red Blood cells transport oxygen from the lungs through the body using the arteries as a channel of movement to all organs.
(2) Enzymes are proteins that catalyze chemical reaction in the digestion of food so as to break food down into a form which can be absorbed by the body.
Sexual reproduction
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