Answer:
To observe the cheek cell,
-
Take a tooth pick use its blunt side to scrap inside the mouth.
- You will see some deposition on the blunt side of tooth pick, make a smear on the clean slide in the center using that tooth pick.
- Add a drop of methylene blue solution and place a coverslip, make sure that bubbles are avoided i.e. coverslip should be placed in the inclined manner.
- Remove the excess solution and observe it under the microscope first under 4X and then under 10X.
Observation:
- The cells observed are squamous epithelial cells. The small blue dots seen inside will be the bacteria from our teeth and mouth.
Answer:
False
Explanation:
Scientist believe that the primitive atmosphere lacked free oxygen. Oxygen is a highly reactive molecule that would have made difficult for complex macromolecules to appear and then create life. Rocks from the precambrian period support this theory.
Anaerobic cells appeared first, then photosynthesis appeared filling the atmosphere with oxygen and the aerobic organism develop cellular respiration to obtain energy, a process more efficient than anaerobic respiration.
Out of the following given choices;
<span>A.
</span>The mouse has a completely different DNA sequence
than the other mice.
<span>B.
</span> The
substituted nucleotide has the same directions as the original nucleotide.
<span>C.
</span>Substitutions in the nucleotides of a mouse's
DNA never affect their phenotypes.
<span>D.
</span>DNA sequences don't determine the color of a
mouse's fur.
The answer is B. Most probably, the nucleotide substitution did not translate to a change in the
amino acid sequence in the translated protein. As you may be aware, most amino
acids are coded by more than one codon. For example, Leucine is coded for by CTT, CTC, CTA, CTG, TTA, TTG.
Therefore, a substitution, that causes a change to either one of the sequences will not
change the amino acid.
a transform boundary because the two plates pass each other in that same plane and the blocks of rock move in opposite horizontal directions .
From the process of respiration chemical energy in the form of ATP.
