Answer:
False
Explanation:
The most specific feature of cardiac muscles is the presence of intercalated discs. Intercalated disc connects the ends of cardiac muscle fibers to one another. The discs have desmosomes and gap junctions. The function of desmosomes is to hold the cardiac fibers together. The gap junctions of cardiac fibers allow muscle action potentials to spread from one cardiac muscle fiber to another. These gap junctions have tubular connexons that form channels and connect the cytosol of adjacent cardiocytes to allow the flow of ions and spread of action potential from one cell to another.
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)
The answer for the above question is the Avascular Necrosis. It occurs as an interruption in the blood flow within the bone resulting in the death of the hematopoietic cells, osteocytes, and marrow fat cells making up the bony structure. It is also called osteonecrosis or ischemic bone necrosis, which occurs when there is loss of blood to the bone, since the bone is a living tissue that needs blood, this interruption of blood supply will result to the death of the bone.
In identical twins, alleles are identical and the order of the bases on the interior of the DNA molecule is identical (Options C and E). It is because genetic material is identical.
<h3>What are identical twins?</h3>
Identical twins refer to individuals produced by the same zygote cell, i.e., they are monozygotic twins.
Since these individuals are produced by the same zygote cell, their genetic material (DNA) will be identical.
Identical twins are useful to understand the exact role of genetics and environment in a given phenotypic trait.
Learn more about identical twins here:
brainly.com/question/17180337
The answer is a pedigree chart.
<span>Pedigree charts are used to explain the occurrence of particular genes from one generation to the next. It gives enough information about family disease history. They are used in families to find out the probability of inheriting some disease. So, if Maria and Juanita are cousins and the genotypes of other members of their family are known, the pedigree chart could predict their genotypes. Still, it is not as precisely as DNA test.</span>
