Answer:
C. Aa and aa
Explanation:
The question tell us that shaded symbols represent individuals who express a dominant trait (or phenotype). This means that symbols that are not shaded represent individuals who express a recessive trait (or phenotype).
A dominant allele (A in this case) will always mask a recessive allele (a in this case) when present and be shown in the organism's phenotype. Therefore genotypes AA and Aa, which both contain the dominant allele A, will both result in dominant phenotypes, while the genotype aa will result in a recessive one due to the absence of a dominant A allele.
Looking at the pedigree chart we can see that individual 1 has a dominant phenotype, and individual 2, a recessive phenotype. Since the only way for an organism to have a recessive phenotype is to only have recessive alleles, organism 2 must have genotype aa. Similarly organism 1 must have at least one dominant A allele, therefore C is the correct answer.
Hope this helped!
The answer is A: Mass extinction.
"Abrupt disappearance of many land and marine species" = extinction of many species.
Characteristics of Lancelets:
Small
Elongated
Marine invertebrate
Lacks a jaw
No sense organs
Has a notochord
Example: Lamprey
Characteristics of Tunicates:
Marine invertebrate
Has an outer coat that is rubbery or hard
Has two siphons
Examples: sea squirts, salps
I hope this is the answer that you were looking for.
Answer:
1) Waterfalls also create erosion. Soft rock erodes, leaving a hard ledge that it washes over. Rocks fall over the waterfall and swirl around in the pool, creating more erosion. The process is repeated, and the waterfall retreats, leaving a gorge behind.
2) Coastal erosion from oceans is always occurring. An eroding beach can lose several feet of sand in one year. In California, waves and rain create mudslides that take down houses by the dozen.
Answer:
The consumption of a drug that inhibits or block the enzyme primase will have problems for the replication of DNA, since it is not possible to synthesize a new strand without this enzyme.
Explanation:
During DNA replication, the enzyme primase is responsible for synthesizing the primers, RNA fragments necessary for the DNA polymerase III to synthesize the new DNA strand.
If for any reason the action of the primase is blocked, the primer could not be synthesized and the effect of DNA polymerase III would be null, so the new DNA strand could not be synthesized.
In DNA replication, the primase contributes to the formation of small fragments of DNA, by the action of polymerase III, which are called Okazaki fragments. These fragments will require the action of another enzyme, ligase, in order to form a continuous DNA strand.
