The picture above is that of a nucleus. the dark dense area is the nucleolus. what is its main function? a) dna synthesis b) ribosome assembly c) protein synthesis d) chromatin formation

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.

there are mainly three domains in biological classification namely; archaea, bacteria, and eukarya.

archaea includes all the prokaryotic cells which are characterized by their lipid membranes. they have branched hydrocarbon which is attached to glycerol through an ether linkage.

bacteria includes all the prokaryotic cells, the cell membrane of which are made up of the unbranched fatty acid chain. in addition, they are attached to glycerol through an ester bond.

eukarya includes all the eukaryotic cells, that is, the cells contain a nucleus and other membrane-bound cell organelles.

they can be autotrophic as well as heterotrophic, unicellular as well as multicellular

they include kingdoms like protista, plantae, animalia, fungi et cetera.

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explanation:

kelp are large brown algae that live in cool, relatively shallow waters close to the shore. they grow in dense groupings much like a forest on land. these underwater towers of kelp provide food and shelter for thousands of fish, invertebrates, and marine mammal species.

e) all of the above