Answer:
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The organic pathway of the carbon cycle moves carbon from the atmosphere, through producers and other organisms in ecosystems, and back to the atmosphere. The geological pathway moves carbon from the atmosphere, through the ocean to rocks and the mantle, and back to the atmosphere
Explanation:
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Natural selection acts directly on those gene variations for traits or phenotypes.
The phenotype of an organism is the physical characteristic and is determined by the organism's genotype. Natural selection selects the genes that produce a certain phenotype by providing suitable conditions for a certain phenotype.
Answer: the mantle B
Explanation: Largest layer resulting in biggest mass.
Answer:
Advantage of gene expression in prokaryotes is it occurs faster than in eukaryotes because transcription and translation occur simultaneously in the cytoplasm, and regulation occurs at the transcriptional level. Whereas disadvantage of gene expression in prokaryotes is that there is no post translational modification and low expression of genes.
Explanation:
Prokaryotic organisms are single-celled organisms that lack a cell nucleus, and their DNA therefore floats freely in the cell cytoplasm. To synthesize a protein, the processes of transcription and translation occur almost simultaneously. When the resulting protein is no longer needed, transcription stops. As a result, the primary method to control what type of protein and how much of each protein is expressed in a prokaryotic cell is the regulation of DNA transcription. All of the subsequent steps occur automatically. When more protein is required, more transcription occurs. Therefore, in prokaryotic cells, the control of gene expression is mostly at the transcriptional level. whereas in eukaryotes, the DNA is contained inside the cell’s nucleus and there it is transcribed into RNA. The newly synthesized RNA is then transported out of the nucleus into the cytoplasm, where ribosomes translate the RNA into protein. The processes of transcription and translation are physically separated by the nuclear membrane; transcription occurs only within the nucleus, and translation occurs only outside the nucleus in the cytoplasm.
