Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein synthesis. In eukaryotic cells, each class of RNA has its own polymerase, whereas in prokaryotic cells, a single RNA polymerase synthesizes the different class of RNA. Other types of RNA also exist but are not as well understood, although they appear to play regulatory roles in gene expression and also be involved in protection against invading viruses.
Answer:
Viruses use their own catabolic enzymes.
Explanation:
Viruses are the infective particles present in the environment which encloses their genetic material which could be wither RNA or DNA enclosed in the protein coat.
The protein coat is made of the capsomers which are arranged in the tubular structure forming capsid. The viruses do not contain the metabolic machinery of their own that is the reason that they do not have replication or transcription or translation machinery. For this they are dependent on the host organisms as they use their machinery.
Thus, the selected option is correct.
Answer:
The correct answer is A: Simple cuboidal epithelium.
Explanation:
Simple Cuboidal Epithelium: These epithelia are formed by a single layer of cuboidal cells, that are <em>as </em>tall as they are wide. They have a rounded, central nucleus. Occasionally these cells present cilia, flagella or <em>microvillus</em> in their apical surface, lining the lumen. Microvillus are fingerlike projections. This epithelium can be found for example in the proximal convolutes renal tubule.
Answer:
A. insects fly around a bright lamp at night
Explanation:
insects are naturally attracted to light due to presence of positive phototaxis. Insects revolve around the light in the same way as electrons do around the nucleus.
Answer A seems like the best choice for this question. Just think about some of the synonyms for therefore—”hence,” “consequently,” and “thus.” Because the adverb therefore often plays the role of a conjunction, it's sometimes called a conjunctive adverb.
B isn’t the correct answer to this question because you use “On the other hand” to introduce two contrasting points, facts, or ways of looking at something.
C isn’t the correct answer because we are not comparing or contrasting anything in this sentence.
D isn’t the correct answer because “Especially” is used in a formal sentence example: She can't be sure she will win, especially at this early stage of the campaign.