Answer:
Chromosome number variation: B. Down syndrome
Loss-of-function allele : D. PKU
Physiological trait
: E. Lactose metabolism
Discovery-based science
: A. Human Genome Project
Genetic cross: C. Model organism
Explanation:
Down syndrome is a condition in which there is an extra copy of the chromosome number 21. Hence, it is a chromosome number variation.
Physiological traits refers to any function of a body. Hence, it matches with lactose metabolism.
Human Genome Project was a project under which the whole genome of the humans were sequenced. Hence, it is a discovery based science.
A genetic cross is made between model organisms to test for the offsprings that would be produced from a cross. Hence, genetic cross and model organism math with each other.
Answer:
The first anticodon leaves the ribosome through the E-site
Explanation:
Translation is the second stage of gene expression. It occurs in the ribosomes (organnelles of protein synthesis) where amino acid sequence is synthesized using a mRNA template. The tRNA (transfer RNA) is responsible for reading the mRNA codon using its ANTICODON, which is complementary to the mRNA codon.
The tRNA reads the mRNA codon and carries the amino acid that corresponds what it reads. tRNA has three binding sites on the ribosome; A-site, P-site and E-site. A tRNA molecule with the complementary anticodon binds to the codon on the P-site, and carries its corresponding amino acid. Another tRNA with complementary anticodon occupies the A-site, carrying the corresponding amino acid again.
Once both sites are occupied, the tRNA on the P-site transfers its amino acid to the one on the A-site to form a peptide bond. This causes the ribosome to shift the tRNA on the P-site, allowing the one on the A-site to be free. When this happens, the anticodon of the first tRNA on the P-site leaves the ribosome via the E-site in order to bind to another complementary mRNA codon and continue the translation process.
If atoms share two , three or more pairs of electrons..they are covalent bonds..for example, methane
if the atoms share only a lone pair of electron contributed by only one of the combining atoms but shared by both ..then it is a coordinate bond ..for example, ammonium ion
