CRISPR-Cas9 is a genetic modification technique that edits parts of the genome of an organism. Using this technique scientists can add, remove, or modify sections of the DNA
sequence.
How can scientists use this technique to control gene expression?
A By activating or deactivating specific genes
B By calculating the number of genes different organisms produce
C By identifying how closely related one individual is to another
D By determining the number of chromosomes in an organism

Getting rid of my account might as well do it with some fun make sure to read all of this it is hilarious a plane was about to crash and there were 5 people on board and only 4 parachutes. the first person said: " i am roy keane, one of the best footballers in ireland. i am worth a lot of money and my fans need me so i think i should be saved." the others agreed and gave him one of the parachutes and off he went. the second person said: "i am gerry adams, a radical irish politician who can really my country and i think i should be saved." the others said: "o.k.", and gave him a parachute. the third person said: "i am george bush, president of the most powerful country in the world. everyone knows i am a really nice guy and everyone thinks i am stupid,but i'm not, so i am taking a parachute." and off he went. there were two people left, the pope and a 10 year old schoolgirl. the pope said: "child, i am old and frail and have lived my life while you are young, with everything before you. you take the parachute and i will stay with the aircraft and take my chance." "it's o.k." said the girl, "there are still two bush picked up my schoolbag."

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.

What kinds of molecules can pass through the cell membrane without any problem?