Portals of entry are the sites where micro-organisms can enter a host and reproduce, causing diseases or infections. There are various portals of entry in the human body. This can include the skin, our mucous membranes, and even our respiratory and gastrointestinal tracts. Portals of exit are where these micro-organisms leave and spread to other individuals. Portals of exit include coughing, sneezing, and some of our bodily fluids.
The surface temperature of white dwarf stars is higher than that of red super giants. White dwarf stars are extremely hot when they form, and they start cooling off as time goes by. Red supergiants, on the other hand, are enormous dying stars, and they are quite cool. So, having this in mind, white dwarves are hotter than red supergiants. Hope I helped! :) If it’s wrong then I’m sorry!
Answer:
D.) repressor DNA-binding site mutation
Explanation:
lacl prevents the repressor polypeptide is a mutant that prevent operon from binding lactose, and thus will bind to the operator and be non-inducible.. This mutant will represses the lac operon whether lactose is present or not and the lac operon will not be expressed. It is also called“super-supperesor".
The lacI locus – One type of mutant allele of lacI (callled I-) prevents the production of a repressor polypeptide or produces a polypeptide that will not allow to bind to the operator sequence.
This is also a constitutive expresser of the lac operon because absence of repressor binding permits transcription.
Its B clearing and farming. Because if you think of it when someone clears trees and bushes they most likely won't come back.
