The main function of the Krebs cycle is to generate energy for the cell. The Krebs cycle is also known as the citric acid cycle and is part of cellular respiration. Cellular respiration is a series of chemical reactions that cells use to break up sugars into a form that the cell can use. Cell respiration requires oxygen to take place. Cellular respiration consists of four stages:1. the breaking down of glucose into molecules (glycolysis)2. the link reaction - this process forms a link between glycolysis and the Krebbs reaction3. Krebbs reaction 4. The electron transport chain
An acid because if its less than 5 its an acid
Producer.
I remember it by thinking: "auto means automatic, so autotrophs automatically make their own food, so they must be producers"
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: B
Explanation: the sun is made of gas, which doesn't all spin together at the same speed like a solid rock would.