Answer:
Las aletas de una ballena y el brazo de un hombre son un ejemplo de órganos homólogos, porque la estructura ósea de las aletas de una ballena es parecida (homóloga) a la estructura ósea de nuestros brazos, debido a que ambas proceden del mismo origen embrionario pero se han modificado para desempeñar funciones ...
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.
Recombination or crossing over occurs during prophase i. homologue chromosomes- 1 inherited from each parent pair along their lengths gene by gene. Independent Assortment is the process where the chromosomes move randomly to seperate poles during meiosis
Answer: Its just called a twisted ladder. If you could give me the options i can answer!!
Explanation:
