Answer:
Part 1:
The four astronomical bodies one could choose to represent the 4 labels in the diagram are
A - universe
B - galaxy
C - solar system
D - Mars
The universe contains galaxies and galaxies holds solar systems which have planets like Mars
Part 2: D or a planet like Mars is unlike all their other astronomical bodies it does not have other astronomical bodies within it thus, its different from rest.
Answer: in order for a scientific investigation to be valid A hypothesis must be tested throughout a Scientific investigation that can gather evidence and support it.
Explanation: in any scientific investigation you have to have a testable hypothesis, without your hypothesis it’s not really a scientific investigation.
Hope this helped!
The teacher should clean the wound
Explanation:
the cut could've gotten something in it
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.
