Answer:
Scientists usually use the potassium-argon method to date rocks that are older than about 1 million years. Uranium-238 is also used for radiometric dating. It has a half-life of 4.5 billion years. It decays to produce lead-206.
After DNA replication has taken place, two molecules, each with one original and new strand is formed. This supports the idea of DNA replication.
Answer:
fur with black hairs
Explanation:
Its because B denotes the dominant gene which express itself and supress the recessive one (b)
Out of the choices given, the mechanisms that drives evolution is natural selection. The correct answer is B, natural selection.
Answer
Operons are cluster of coordinated genes, including structural genes, an operator gene, and a regulatory gene.
Explanation:
In the The repressible operons, The transcription is usually on and repressor is in inactive form, So the specific genes are transcribed. While a regulatory molecule act as corepressor and binds to repressor protein to activate it. The repressor protein cause the inactivation of repressible operon (as the name indicate). E.g., Tryptophan Repress the trp operon.
A high level of product act as regulatory molecule (Corepressor) and turn off the operon, So anabolic pathways or synthesis of essential components are controlled by repressible operon.
In the Inducible operons, the transcription is usually off and repressor is in active form. So there is no transcription of genes. Specific Metabolite cause the activation of operon e.g lactose cause the induction of lac operon.
As a metabolite induces the operon, So they control the Metabolic pathways or breakdown of a neutrient.
