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)
Answer:
A. Photosynthesis
Explanation:
Photosynthesis is a process in plants produce food materials by absorbing carbondioxide from the atmosphere which decreases the concentration of carbondioxide in the atmosphere. In photosynthesis reaction, plant take water from the soil and carbondioxide from the atmosphere in the presence of sunlight produces glucose and oxygen. Glucose is stored in different parts of plant such as grains, stem and roots while oxygen is released in the atmosphere.
The answer is B) hope this helped you
Answer:
Fungi
Explanation:
Fungi are multicellular,with a cell wall, organelles including a nucleus, but no chloroplasts.
Answer:D.D.) Suspend the cells in liquid agar culture and monitor which culture continues to grow.
Explanation
Options A-C are correct except D.
→Increase in Telomere length is indicative of abnormal growth, cancer cells can reactive telomerase to increase cell's length.
→Once a monolayer is reached; this a stage of a complete normal cell division , a cell that goes beyond this stage must be mutated. assuming all other factors are constant .
Uncontrolled cell division is an indication of virulent growth in mutated cells.
<u>Cancer cell requires a ,medium of living host to thrive, alga medium will not support growth for carcinoma cells -the correct answer. </u>
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Completed Que.
:Imagine that you are a graduate student working in a cancer lab. You accidentally mix unlabeled tubes of carcinoma cells with tubes of normal epithelial cells. Which of the following is NOT a possible strategy to allow you to distinguish which tubes contain carcinoma cells?
A.)Monitor telomere length over time during multiple cell divisions.
B.) Plate the cells in culture and look for the culture that stops dividing once a monolayer is reached.
C.) Monitor the rate of cell division.
D.) Suspend the cells in liquid agar culture and monitor which culture continues to grow.
