Answer:
Plants and animals share many characteristics, but they are different in some respects. Animals usually move around and find their own food, while plants are usually immobile and create their food via photosynthesis. ... Animal cells absorb nutrients from food, while plant cells use plastids to create energy from sunlight.
Explanation:
Answer:
GAR and AICAR transformylase
Explanation:
Tetrahydrofolate is essential for purine and pyrimidine synthesis, its deficiency can lead to inhibition of nucleic acid such as DNA and RNA and protein synthesis, which are important for the growth and survival of both normal cells and cancer cells. N-10-formyltetrahydrofolate acts as a donor of carbon atoms to the actively growing bases. It contribution is mediated by the action of the Glycinamide Ribonucleotide (GAR) transformylase and the N-5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) transformylase.
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.
It would be the endocrine system
