Insufficient parathyroid hormone
production in the body could result in low levels of calcium in the blood which
can cause cramping and twitching of muscles or involuntary muscle contraction
in hands and feet, dry skin and several other symptoms in the body.
After the power stroke, ADP is released<span>; however, the cross-bridge formed is still in place, and actin and myosin are bound together. </span>ATP can<span> then attach to myosin, which allows the cross-bridge cycle to start again and further </span>muscle contraction can occur<span> </span>
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:
A food web consists of many food chains. A food chain only follows just one path as animals find food. eg: A hawk eats a snake, which has eaten a frog, which has eaten a grasshopper, which has eaten grass. A food web shows the many different paths plants and animals are connected.
I would answer but you didn't put any pictures so I can't see what shows anything.
