Answer:
integumentery system
Explanation:
your skin is actually the first protection against illness-causing pathogens.
Crusts and uppermost mantle
The sun like all stars is constantly using up its (Fuel)
so eventually like all other stars it will create a supernova and we would all die
thankfully that won't happen for another 5 million years
The correct answer is d: cDNA.
<span>cDNA or complementary DNA is DNA synthesized usually from messenger RNA (mRNA) by the enzyme reverse transcriptase. Because this molecule is from mRNA it contains only exons. cDNA is also produced naturally by retroviruses, for example, HIV virus.</span>
The communities plus abiotic and biotic surroundings is called an ecosystem
