Answer:
c and b
Explanation:
cause I believe that because of the populations and polutions that is cause of humans we are now lack of protective shield and green gases within our atmosphere
MRNA or messenger RNA. As the central dogma of biotech goes, DNA is transcribed to mRNA which is translated to tRNA, after which the amino acids form peptide bonds and form proteins. So when you see transcription, the first thing you think of is DNA to mRNA.
The nervous system communicates through electrical impulses and the communication is very fast. It works in a relay fashion, from point to point comparable to the way the old telephones systems used to work.
The endocrine system communicates by chemical signals via the bloodstream. Hormones are secreted into the blood and extra cellular fluids, then transported to target cells, which must bear a receptor to be able to bind to a specific hormone, and respond.
Hormones are chemical messengers secreted into blood or extracellular fluid that affect the function of other cells.
Endocrine communication is not quite as fast as the nervous system communication
So that it can protect exposed tissue, a layer of meristematic cells, cork cambium, or phellogen rises from the cortex.
It depends on the life stage that the star is in. Currently, in the mid-life stage, the sun is still fusing hydrogen into helium, so the maximum here is helium; however, far in the future when the star is nearing its final days, it can fuse atoms into elements as heavy as iron and nickel.