Answer:
a. + glucose, + lactose = On
b. - glucose, - lactose = Off
c. + glucose, - lactose = Off
d. - glucose, + lactose = On
Explanation:
Lac operon has both types of control, repressible and inducible.
Whenever glucose level is low in the cell, an enzyme known as adenylyl cyclase raises the level of cAMP which forms a dimer with CRP protein and they both act as activator of lac operon and cause expression.
Apart from this, when lactose is present in the cell, β-galactosidase enzyme metabolizes lactose to form allolactose which causes allosteric repulsion in the lac repressor and causes its removal from the operator. As soon as repressor is removed lac operon gets activated.
In wild type lac operons, the expression of lac operon occurs when glucose level is low in the cell and lactose is present but in this mutant presence or absence of glucose will not make a difference because CRP will bind Plac promoter independent of cAMP level i.e. activator CRP will work even in high glucose concentration. If lactose is present then lac operon will always express so in option 'a & d' lac operon will express but in option 'b & c' it will not express.
I would say the garden has more oxygen. oxygen and carbon dioxide is completely 2 different elements. and since there are more plants, most likely, if it has enough sunlight, the garden will have a better oxygen, because for plant photosynthesis it releases oxygen as their by product.
however please note that if the garden is dark, no light, the garden will lower the oxygen concentration because plants respire and they release carbon dioxide instead. photosynthesis only occurs in light condition as its the source of energy.
Answer:
<em>A beautiful waterfall</em>
Explanation:
Aesthetic value can be described as the value of an object or event, whether occurring naturally or being constructed. It can be described as the virtue of an object and its worth. The aesthetic value determines how much of an object or event is pleasing to the eyes or how much it can be displeasing.
A beautiful waterfall for sure increases and enhances the value of a healthy ecosystem. It is a sight which offers pleasure to the eyes and soul.
<span>The part of female reproductive system that is responsible for the nourishment, holding and protection of the embryo or fetus is the uterus, also known as the womb. It also provides support to the bladder, pelvic bones and other organs. </span>
