<span>Endorphin. Endorphin are pepetide hormones secreted by the central nervous system and the pituitary gland. They inhibit the transmission of pain signals; they also produce a feeling of euphoria very similar to the ones produced by other opioids. Its 1 production is usually triggered by various human activities although they are produced in response to pain. Carrying out frequent exercise usually stimulates the release of beta-endorphin in the human brain known as runner's high. This is the probably the reason Mobombi could finish the race pain free.</span>
Answer:
Explanation:
The correlation between sea surface temperature and water vapor is that both are driven by seasonal changes. They both increase in the hemisphere during summer. Seasonal changes in water vapor are, however, more evident across the land, largely due to changes in land surface temperature.
Chorionic Villus Sampling. Definition: CVS is a test where the doctor collects a tiny piece of the placenta, called chorionic villus, which is then tested to check for chromosomal or genetic disorders in the baby.
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.
