Today, the Earth's axis is tilted 23.5 degrees from the plane of its orbit around the sun.
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:
is this a true or false question
Lost to the environment in the form of heat.
Answer:
Here, the stimulus which is discussed in the question is the Suckling stimulus which is also known as Suckling reflex.
Suckling by a child stimulates the suckling reflex system. The stimulus (information) reaches to the Hypothalamus. Hypothalamus triggers the TRH (thyrotropin-releasing hormone) which further triggers the releases of the Prolactin (PRL) hormone by the Anterior Pituitary.
Finally, when Prolactin reaches the blood, it stimulates the Mammary glands which being stimulated, start to produce milk.
Explanation:
The main function of Prolactin is to produce milk. Prolactin production is mainly controlled by Hypothalamus. Prolactin hormone is produced in Pituitary, uterus, etc. The prolactin hormone production is also controlled by the estrogen.
- Prolactin regulation is also controlled by Dopamine and Oestrogen. Both of them regulates the onset and stoppage of prolactin production by sending the information to the pituitary gland. Dopamine mainly blocks the production when the level of prolactin is too high in the blood. Oestrogen mainly increases the production when the level of prolactin in the blood is too low.
- Not only Prolactin boost up the milk production but it also helps in maintaining the female's body metabolism, immune system, regulating the menstrual cycle, and regulating body fluid levels. In males, it increases sperm production.
