Answers:
- Transcription takes place in the <u>nucleus</u> of the cell.
- In this process, an enzyme called<u> RNA polymerase </u>unzips approximately <u>14 base pairs of DNA </u>and adds new nitrogenous bases to the template strand to create a new strand of mRNA.
- This new strand has one difference in the base pair rules. In DNA, adenine pairs with <u>Thymine.</u>
- In mRNA, adenine pairs with <u>Uracil.</u>
Explanation:
Transcription is the first step of expression of DNA into the protein product. During transcription, the DNA is replicated in the form of RNA (Ribo nucliec acid). It takes place in the nucleus of the cell while the second step of gene expression, translation takes place in the cytoplasm of the cell.
Once the transcription is completed, all the information of a particular DNA segment is obtained in form of RNA segment. RNA contains exactly the same genetic information as contained by DNA, the difference is it has base Uracil in place of Thymine.
The general steps of the translation are six:
- An enzyme called RNA polymerase unwinds or unzips a certain segment of DNA.
- This unwinding occurs at a specific site called promoter region and forms transcription bubble.
- The enzyme RNA polymerase starts to add RNA nucleotides that are complementary wit the specific region of DNA>
- RNA nucleotides form the bonds with each other to form a complete sequence of RNA.
- The newly synthesized RNA strand detaches from DNA template
- Rewinding of DNA occurs and mRNA is ready to go into the next stage of gene expression called Translation.
Hope it helps!
The skin is an example of a non-specific defense.
For example, bacteria or diseases have trouble entering a healthy person's skin because it is formed by closely packed cells with multiple layers and a substance called keratin that protects is.
On the other hand, the immune system is a specific defense mechanism.
When bacteria is able to enter the body in cases of fever for example, the immune system is activate and sends out protector cells such as the white blood cells to combat infection.
It should be "population" but I'm not 100% sure. I hope this helps a little bit.