Answer:
SA Node
Inter-nodal Pathways
AV Node
AV Bundle
Bundle Branches
Purkinje Fibers
The SA nodes functions first for setting pace for the heart, then the inter-nodal pathway make link b/w SA and AV node. AV node is site of delay when contraction of atria occurs. AV bundle is the mean of electrical link b/w atria and ventricle. The conveying of impulse to the inter-ventricular septum occurs through bundle branches, while conveying of impulse throughout and along the walls of ventricle occurs through Purkinje fibers.
They have kingdom, class, and phylum, I’m kind of confused about the answer because of that.
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1. 4th option
2.the 3rd option
3.the 1st option
4. the 2nd option (i think)
5. 3rd option
page 2:
1. 3rd option i think
2.3rd option
3.2nd option
4.2nd option
5.3rd option (i think)
Lysosomes use a degenerative enzyme to eliminate un necessary materials from the cell and recycle parts that can be re used, much like a recycling centers eliminate waste from cities and find ways to reuse it.
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)
