I believe it is A (Adenine)
B. The nervous system collects and responds to information about the external and internal environment.
A population of frogs with
slightly different coloring is an example of microevolution. Microevolution is
the changes in the gene pool of a population that can be measured and observed in
short periods of time within a population. Microevolution can take place in
several ways such as gene flow, genetic drift, mutation and selection.
Answer:
Regulatory sites e.g enhancers and silencers
Explanation:
Gene expression involves the synthesis of gene products usually proteins and RNA. However, a certain product might not be needed at all or in small quantity. Gene regulation mechanism is the process that makes this happen. Gene regulation is the mechanism that acts to induce or repress the expression of a gene.
Gene regulation involves controlling the rate and manner of gene expression which is achieved through a set of regulatory proteins called transcription factors. Transcription factors bind to specific regulatory nucleotide sequences and help to turn "on or off" specific genes in the DNA.
Transcription factors can either be ACTIVATORS or REPRESSORS depending on whether they boost or inhibit gene expression. The binding sites for these regulatory proteins called TRANSCRIPTION factors are the regulatory nucleotide sequences on the DNA called enhancers and silencers.
Lysosomes, because they are the organelles that secrete these hydrolytic enzymes and help break down old organelles, viral/bacterial invaders, and food particles.
