Answer:
Substance
<u>Review</u>:
⇒ One of a class of substances that cannot be separated into simpler substances by chemical means.
<u>Compound</u>:
⇒ A pure substance composed of two or more elements who composition is constant.
Humans belong to domains eukaryota. The domain includes four of the six kingdoms in life: Protista, Fungi, Plantae and Animalia. The other two domains are Archaea and Bacteria.
Answer:
provide protection against pathogens
Explanation: