Answer:
A = Activator
B = Effector
Explanation:
An activator is a protein which typically binds to a short (50–1500 bp) region of DNA which might be located either upstream (mainly) or downstream of a gene so as to cause increased transcription. This particular region of DNA is known as enhancer and activator is also known as transcription factor. Activator is a trans-acting factor which binds to the cis-acting factor which is enhancer so as to enhance transcriptional expression.
But another protein named as effector may restrict activator from binding to the enhancer leading to a decrease in transcriptional expression by binding to the activator allosterically. Allosteric binding of effector to the activator causes conformational change in activator so it can no longer bind the enhancer.
Photosynthesis, respiration and combustion.
Answer:
synapse is the connection of the axons of one neuron and the dendrites of another, myelin is the substance that protects the grey matter from the bony surface of the head for example, nucleus of a neuron is the main part of the nersous cell and neurotransmiters are the substances that make synapses posible ( and sometimes efficient)
