Thought and action are the two main functions
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.
My(myo) may be is the right one
Answer: <em>Interphase is the phase in the cell cycle during which cells that will undergo mitosis prepare for division. In interphase, DNA of the cell copies. After that cell undergoes mitosis, which is the phase of the cell cycle during which cell divides on two identical. Mitosis consists of four phases:</em>
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<em>1. Prophase: Chromatin in the nucleus condenses and chromosomes pair up
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<em>2. Metaphase: Chromosomes line up at the centre of the cell.
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<em>3. Anaphase: The sister chromatids separate from each other to the opposite sides of the cells.
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<em>4. Telophase and Cytokinesis: Membrane forms around each set of chromosomes on two opposite sides of the cells and cell divides into two identical daughter cells.</em>
