D. I just took the test on USA Test prep so ya, remember to mark this the brainlyest answer
Operons are the functional units of transcription and genetic regulation. These are found in bacteria and their viruses where genes coding for functionally related proteins are grouped along the DNA.
The two types of operons are- inducible and repressible.
They regulate the genes as in negative inducible operons, a regulatory repressor protein is bound to the operator. It prevents the transcription of the genes on the operon. If positive inducer is present, it binds to the repressor and changes its conformation so it is unable to bind to the operator.
<span>Synaptic cleft or the terminal buttons that transmits neurotransmitters to the next neuron, received by its dendrites and is relayed now throughout the system until it reaches the brain.
The messages must travel the distance of the nerves to the brain which are processed and made decisions, from the distance of the nerves from the sense organs, then travel back to the muscles that need to respond through the nerves.<span> </span></span>
The answer is D. i past this class with a 98 overall score.
Answer:
c. ¼ heavy, ¾ light
Explanation:
DNA replication follows semi conservative model which means that both the strands separate during replication and the newly formed DNA molecule has one old and one new strand. If instead of semi conservative, conservative mechanism is used, old strands will not separate from each other and the two newly synthesised DNA strands will come together to form a DNA molecule.
Here the cells were first grown in heavy 15N medium so all the DNA molecules had 15N and thus were heavy. Then the cells were transferred to 14N medium where only lighter 14N were available for replication process.
In first generation, 14N DNA molecules were synthesised from 15N DNA molecules so 1/2 DNA molecules were 15N and other half were 14N. In the second generation, 14N molecules will give rise to new 14N molecules and 15N molecules will also give rise to 14N molecules hence 1/4 molecules will be 15N (heavy) and 3/4 will be 14N (light).
