The correct answer is:
<h3>a.
Entropy increases going from one trophic level to another.</h3><h3>Explanation:</h3>
Entropy progress going from one trophic level to another. Entropy is a division for the disorderliness of a system. As the trophic level move to the other, energy is lost so more chaos occurs which inflates the entropy.
Toxins in the soil would enter through the root system first.
Answer:
C) Through genomic imprinting, methylation regulates expression of the paternal copy of the gene in the brain.
Explanation:
The pattern of gene expression wherein either paternal or maternal gene is expressed in specific cells while the other one is prevented from expression is known as genomic imprinting.
In the given example, the maternal copy of the gene on chromosome 15 is expressed in brain cells while its paternal copy is not expressed in these cells. Hence, the pattern of expression of this gene is regulated through genome imprinting. One of the mechanism is methylation of cytidine residues of CpG islands of the DNA that are more frequently present within promoters of the genes.
When the cytidine residues of these sequences are methylated into 5-methylcytidine, the transcription factors do not bind to these promoters preventing the expression of these genes.
Hence, methylation of cytidine residue in CpG islands of the promoters of the gene present on chromosome 15 could have silenced its expression in brain cells.
Answer:
precession
Explanation:
The orbit isn’t the simple ellipse, rather it is one that moves a little, loop after loop. This motion is called precession, and you may have heard about it when astronomers talk about the precession of the orbit of Mercury
