Answer/Explanation:
DNA polymerase is the enzyme responsible for replicating DNA. It is hugely important that is performs its functions accurately, as if incorrect bases are incorporated this can lead to mutations that disrupt the structure and function of genes. It adds nucleotides in a 5' - 3' direction only.
DNA polymerase III also has high processivity, which means that for every time it binds DNA, it is able to add many bases before it becomes dissociated.
A. DNA polymerase avoids the incorporation of improperly paired nucleotides in two ways:
- The first way depends on the structure of the enzyme. If the nucleotide that the enzyme is in the process of adding is not complementary to the template, then the nucleotide will not align with the template, and thus it is more inefficient to add. This inefficiency means the nucleotide is more likely to leave the active site before it is added, and DNA polymerase can replace it with the correct nucleotide.
- It also has proofreading capabilities. This means, when an incorrect base is added, it recognises the error and can fix this. It can do this because it possesses 3'-5' exonuclease activity. That means, it can chop out incorrectly added bases.
B. Ribonucleotides are the nucleotides that are incorporated into a growing RNA molecule. They are different from deoxyribonucleotides because of the differences in the sugar backbone (ribose vs deoxyribose). Their incorporation would disrupt the structure and function of the DNA, leading to problems with transcription and replication.
DNA polymerase avoids incorporating these nucleotides primarily because of the structure of the enzyme. Ribonucleotides cannot fit into the active site of DNA polymerase due to what is called a "steric filter" or "steric gate". This gate/filter function is performed by specific amino acid residues which usually have a bulky side chain and thus block the incorporation of the 2'OH of the ribose sugar (which is lacking in the deoxyribose sugar)
I believe the answer is Gene splicing because they remove specific genes in order to create a transgenic organism.
I hope this helps!
Answer:
Explanation:
A retrovirus is an RNA virus that is duplicated in a host cell using the reverse transcriptase enzyme to produce DNA from its RNA genome. The DNA is then incorporated into the host’s genome by an integrase enzyme. The virus thereafter replicates as part of the host cell’s DNA. Retroviruses are enveloped viruses that belong to the viral family Retroviridae. A special variant of retroviruses are endogenous retroviruses, which are integrated into the genome of the host and inherited across generations. Endogenous retroviruses are a type of transposon.
Answer:
The answer is C- Lysosomes are present in both bacterial and animal cells.
Explanation:
Lysosomes contain digestive enzymes inside them, which when released break down damaged cell parts. These enzymes are <em>acidic</em> in nature and are separated from other organelles with the help of a membrane.
Lysosomes help in<em> killing bacteria and virus</em> invading the cell body. Lysosomes also take part in the process of cell death known as '<em>apoptosis</em>'. This happens only when a certain cell is beyond repair.
Lysosomes are present in plant cells, animal cells, bacterial and yeast cells.
Answer:
A: The balloon expands
Explanation:
Since the heat is absorbed by the balloon, the molecules inside will spread apart. When this happens, the balloon will also expand as the molecules expand which therefore the balloon grows.
