Answer:
True
Explanation:
Tobacco is consumed during smoking which contains an addictive substance called Nicotine. Nicotine exerts its effect on the body by stimulating the acetylcholine receptors in the neurons. The stimulation of these receptors stimulates another neurotransmitter like glutamate, dopamine and GABA which produce addictive effects in humans.
Since the acetylcholine is involved in stimulating the other neurotransmitters therefore true is the correct answer.
Thus, true is the correct answer.
Paul Zamecnik and his colleagues carried
out an experiment to track the fate of radioactive leucine molecules attached
to tRNAs (Transport RNAs). In their experiment, they found out that amino acids
are transferred from tRNAs to proteins. Paul Zamecnik, an American scientist, played
a major role in the early history of molecular biology.
Artifact selections benefits humans by helping us learn what had happened in the past.
Answer:
chiasmata
Explanation:
Chiasmata is the meeting point of homologous chromatids regarding meiotic cell division.
This structure conforms to homologous chromosomes when, in meiosis, part of the arm of each chromosome breaks and is recomposed into its homologous. This phenomenon, which is extremely important for evolution, is called chromosomal permutation or crossing-over. This phenomenon is associated with gene linkage, that is, linkage, which provides greater genetic variability and different gametic percentages than would be found according to Mendel's second law.
Based on this, we can conclude that the first suggestion that chromosomes could physically exchange segments came from the microscopic identification of chiasmata.