Each cell expresses, or turns on, only a fraction of its genes. the rest of the genes are repressed, or turned off. the process of turning genes on and off is known as gene regulation. gene regulation can occur at any point during gene expression, but most commonly occurs at the level of when the information in a gene's dna is transferred to mrna. a) post-translation b) replication c) transcription d) translation

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Connection compare and contrast genetic engineering to the process of natural selection. select all statements that are true.

Approximately what portion of the foods that we eat have been genetically modified in some way? a. fewer than 10% b. about 50% c. nearly 100%