Answer:
The type of mutation that occurs when in the DNA strand there is a change from guanine to cytosine is a nonsense mutation, since the triplet that should encode the amino acid encodes a stop codon and the protein cannot be completely synthesized.
Explanation:
The nonsense mutation consists of a change in one of the bases of the stranded DNA, which is transcribed into an altered mRNA, producing a stop codon, instead of an amino acid.
In the table it is observed that the CCA codon is a stop codon that cuts off the protein synthesis prematurely, leaving it incomplete and probably non-functional.
Sometimes this type of mutation can alter the sequence of amino acids but the protein may be complete enough to partially fulfill its function.
Answer:
The answer includes all of the options.
Explanation:
Some of the major changes that happened in agriculture during the 1920s include the use of electrical tools and vehicles and chemical fertilizers. These changes along with their low availability to the average farmers made it harder for them to compete with agricultural corporations who could use these advanced methods easily. Hybrid seeds were also used by corporations to get increase the yield of the fields. The answer includes all of the options.
I hope this answer helps.
Answer:
c. a high percentage of very long chain saturated fatty acids
Explanation:
Saturated fatty acids do not have double bonds (they are saturated with hydrogens), so their tails are relatively straight. Unsaturated fatty acids, on the other hand, contain one or more double bonds, which often produces an elbow or bend. (You can see an example of an unsaturated bent tail in the phospholipid structure diagram that appears at the beginning of this article.) Saturated and unsaturated phospholipid fatty acid tails behave differently when the temperature drops:
- At colder temperatures, the straight tails of saturated fatty acids can be tightly bound, producing a dense and quite rigid membrane.
- Phospholipids with unsaturated fatty acid tails cannot bind so closely due to the bent structure of their tails. For this reason, an unsaturated phospholipid membrane remains fluid at lower temperatures than a saturated phospholipid membrane.
Most cell membranes contain a mixture of phospholipids, some with two saturated (straight) tails and others with a saturated tail and an unsaturated (folded) tail. <u>Many organisms — fish, for example — can adapt physiologically to cold environments by changing the proportion of unsaturated fatty acids in their membranes, that is, increasing the proportion of saturated long-chain fatty acids.</u>
In addition to phospholipids, animals have an additional component in their membrane that helps them maintain fluidity. Cholesterol, another type of lipid that is embedded between the membrane phospholipids, helps decrease the effects of temperature on fluidity.
Answer:
C. 3 indirect transmissions
Explanation:
In epidemiology, direct transmission is considered to occur when an individual has direct contact with a pathogen, which infects him and develops a disease. Indirect infections, on the other hand, occur when individuals come into contact with the pathogen through a transmission vehicle.
In this case, we can conclude that in the question above, there were 3 cases of indirect transmission. This is because all people who had contact with the pathogen, established that contact through the contaminated marker. In this case, the marker is a transmission vehicle.