When two experiments are identical except for one variable, the experiment is called a controlled experiment
They adapt because they can replicate quickly (have many generations within short period of time) and accumulate mutations. Mutations in their genetic information allows them to bypass the host's immune system or resist to antibiotics. These mutations are successfully carried to the next generations of bacteria and allows them to thrive in their new environments. <span />
Answer:
See the answer below
Explanation:
After routinely cleaning the microscope and ensuring that all the parts are working fine, Dylan would have to <u>place the slide on the stage of the microscope, switch on the light source, and adjust the diaphragm of the condenser to ensure that adequate light gets to the slide on the stage</u>.
Thereafter, Dylan would need to<u> turn the revolving nosepiece in order to shift to the lowest objective of the microscope</u> assuming it is not already in place. Then,<u> the slide on the stage is brought into focus (by viewing through the eyepiece/ocular) by using the coarse/fine adjustment knob to bring the stage up/down.</u>
Once the slide is brought into clear focus, <u>the revolving nosepiece is then turned to switch the x20 objective. </u>Generally, at higher objectives, the coarse adjustment knob is rarely needed and the fine adjustment knob is solely used instead to bring the slide back into focus. Thus, Dylan can see the cells of the onion at the desired objective.
Well, certain stem cells are able to become any kind of (somatic) cell (totipotent stem cells), which helps in organ regeneration, etc. the only problem is that removing even one stem cell from an embryo kills the embryo, and people dont like that.