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.
Answer:
it reflects green light and absorbs other colors.
Explanation:
The term pigment derives from the Latin pigmentum, which means the <em>substance that produces color</em>.
Pigments provide color to cells and tissues.
In vegetables, we can find different pigments, such as chlorophyll or carotenoids, among others. Plants use these pigments during the photosynthesis process to absorb sunlight and fixate carbon dioxide. Stem, flowers, and other tissue have pigments in their cells that define the organ´s colors.
Pigments are chemical molecules that produce color by the selective absorption of sunlight. Whenever white light meets a pigment, some wavelengths are absorbed by the pigments while others are reflected. The color expressed is the product of the reflection. The reflected spectrum is perceived as color and determined to be the pigment color or the color of an object or organism.
The color that tissue or vegetal organ express will depend on the pigment concentration or the combination of many of them.
The green color is ordinary in most vegetable species. Chlorophyll is responsible for this coloration, present in almost every vegetable species. This pigment absorbs blue and red wavelengths. But they reflect spectrums of green wavelengths, meaning that the expressed color is green in different tones.
Answer:
<h3>metabolic short term</h3>
Explanation:
<h3>Reactive hyperemia is the blood flow response to blood flow Occlusion whereas active active is a blood flow response to increase tissue metabolic activity</h3>