It means, process of eliminating waste matter..
The best description about the brain stem is: it is the most important organ of our body's survival. It connects the brain and the spinal cord, controls the vital organs like the lungs and heart and it also coordinates the many essential body reflexes.
The only correct answer in this case is B - a stroke.
None of the other answers could be counted as correct here.
While A - a heart attack is conceptualy similar, when we're talking about a heart attack, we're talking about not enough oxygen that gets delivered to the heart - because something is blocking it.
C - hypertension on the other hand means someone has a higher blood pressure than is usual for a regular human being, which puts more strain on his cardiovascualr system.
and D - atherosclerosis doesn't come even close to be correct :)
PP- purple homozygote
pp- white homozygote
Pp- purple hetrozygote
If these flowers cross, we obtain heterozygote offsprings with a genotype: Pp (100% of them will be like this)
Now, if those offsprings cross with each other: Pp x Pp
results:
1/4 would be purple homozygote -> PP
1/4 would be white -> pp
2/4 would be purple heterozygotes -> Pp
Genotipic ratio: 3:1 (3 are purple; 1 is white)
Translation of mRNA into a peptide occurs in sequences of 3 nucleotides called codons. Each codon codes for one amino acid. Therefore, as the ribosome reads the codon sequence, it recruits a t-RNA carrying the respective amino acid. A peptide bond is thereafter formed on the growing amino acid chain before the ribosome translocates to read the next codon. This continues until the ribosome reads a stop codon signaling the end of the peptide.