I believe the answer is protein
In all types of chemical reactions, bonds are broken and reassembled to form new products. However, in exothermic, endothermic, and all chemical reactions, it takes energy to break the existing chemical bonds and energy is released when new bonds form.
Answer:
Explanation:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. ... The skin stops pathogens from entering the blood, at least when you're not bleeding. The tears, mucus, and cilia trap them and help push them back out of your body.
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Carbon, hydrogen, and oxygen are used during photosynthesis