He basically made the first safe and effective vaccine for the disease Polio
Ribosomes and mitochondria are two types of organelles.
Answer:
d. induction
Explanation:
A repressor is a protein capable of inhibiting target gene expression by binding to both operator sites and gene silencers. A DNA-binding repressor inhibits the interaction between the RNA polymerase and the DNA promoter sequence, thereby suppressing transcription into RNA. Moreover, the RNA-binding repressor is a protein that binds to the messenger RNA (mRNA) molecule in order to prevent its translation into protein. An inducer can start transcription by interacting with the repressor, thereby separating it from the DNA operator sequence.
Animal behavior researchers often refer to an activity associated with punishment or reward as an operant. The basis for training animals is the operant conditioning. It is a learning process where the animal would learn base from its behavior as it responds to its environment. In this type of learning, the behavior is either increased or decreased by the results that follows the action. It uses rewards and punishments in order to associate with the behavior. For instance, you are trying to teach your dog to fetch an object, if he succeeds in fetching the object, then you give your dog a treat. The dog would think that what it is doing is good and that it would get a reward from it so it would start learning the behavior.