The endocrine system is comprised of endocrine glands that secrete hormones directly into the blood rather than through ducts. Glands are organs in the bodies of humans or animals that secrete chemicals for bodily use or to go into the environment. Ducts are tubular canals in the body that carry secretions from glands.
Answer:
Neutrophils represent the first line of defence in response to invading microbes, by phagocytosis of pathogens and/or release of antimicrobial factors contained in specialised granules.
<span>d- They take in oxygen gas dissolved in the water through their gills.
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C. If your hypothesis is proven then it eventually becomes true. The exact definition for scientific theory is an explanation that can be proved with repeated explanation.
