Correct answer: Option D- DNA ligase
Explanation: In option A, thymine is a nucleotide, so it is present throughout the replication process, wherever it is required. It is added to the newly formed DNA. In option B, Helicase enzyme is active during initiation and elongation stage, as it facilitates the opening of the winded DNA strands. Option C is nucleotidase and it has no role in DNA replication. So, the correct answer is DNA ligase, which is option D.
The okazaki fragments formed during DNA replication are sealed at the end. And in this step, DNA ligase is used. It catalyzes the formation of phosphodiester bond between the nucleotides of okazaki fragments. So it is the last active molecule of the process.
<u>The right answers are:</u>
HOX genes are very similar in all animals.
Many species share much the same DNA.
Plant and animal cells have almost all of the same structures.
When you combine the genotypes in the Punnet square you get :
1. EeRR
2.Eerr
3.EeRr
4.eerr
The ratio would be typical for a dihybrid cross: 9 of the individuals with both dominant traits, 3 of the individuals dominant for one trait, 3 dominant for the other trait and only one recessive for both traits.
There will be 9/16 of ebony flyes with red eyes
3-16 of ebony flies with orange eyes
3/16 of yellow flies with red eyes
1/16 of yellow flies with orange eyes
