Answer:
Answer choice:Petroleum
Explanation:
Petroleum (crude oil and natural gas plant liquids): 28% Coal: 17.8%
Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. Such factors as stress, caffeine, and excitement may temporarily accelerate your heart rate, while meditating or taking slow, deep breaths may help to slow your heart rate.
BE CAREFUL. Here we ask about the nucleolus precisely and not about the nucleus in general, the precise role of the nucleolus is to assemble the ribosomal RNA and the ribosomal proteins to form the ribosomes. So the answer is B.
In cell biology, the nucleolus is the largest nucleus subcompartment of eukaryotic cells. This particular space of the nucleus is not delimited by a membrane, nevertheless some authors consider it as an organelle and others do not. The number of nucleoli can vary during the cell cycle (usually only 1 in G0 phase).
The nucleolus is composed of proteins, DNA and RNA and is formed around particular chromosomal regions called NOR (Nucleolar Organizing Regions).
It is in particular the place where the transcription of the ribosomal RNAs (5.8S, 18S and 28S rRNA), the processing of these ribosomal RNAs from precursors and the first part of the assembly of the two ribosome subunits takes place. with the association of certain ribosomal proteins. The end of the ribosome assembly occurs in the cytoplasm on mRNA after export of pre-ribosomes through the nuclear pore.
The answer is number 4 hope this helps
