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.
The correct answer is catalyst. Hope that helps.
Answer: Mesopotamia, china, indus River Valley, the mesoamerican empires..... in this case, the two rivers are the tigris and Euphrates. Mesopotamia. The name Mesopotamia was given to the middle eastern civilizations that existed between the Euphrates and Tigris Rivers. :)
.dont taste or sniff chemical
Tasting and smelling some chemicals can be dangerous and even deadly.the best way to know what is in a container is to label
. Don't play mad scientists
This result in mixing chemcals to see what happens the result could be explosion ,fires,or releasing toxic chemicals
.Dress for the lab
This is a safety rule because clothing is one of your best form of protection against an accident wear covered shoes,long pants,and keep your hair tied so it cant fall into your experiment
The mosaic nature is due to the numerous proteins that
are entrenched in the phospholipids bilayer, fluctuate in shape, size and
patterns in the same way as the stones or tiles of a mosaic.
the flexibility is due to individual phospholipids molecules which can move virtual
to one another and gives the membrane a flexible structure that is constantly
changing shape
hope it helps