Answer:
G1 phase: 2C
S phase: 4C
G2 phase: 4C
Meiosis-I: 2C and Meiosis-II: C
Mitosis: 2C
Explanation:
Let's suppose that a cell with 2C DNA content enters the cell cycle. As the G1 cell with 2C content would enter the S phase, DNA replication would double the amount of DNA. Therefore, the cell by the end of the S phase and in the G2 phase would have 4C DNA.
If the G2 cell with 4C DNA enters meiosis-I, separation of homologous chromosomes to the opposite poles in anaphase-I would reduce the DNA content to 2C. Therefore, the cell by the end of anaphase-I would have 2C content. Meiosis-II would further reduce the DNA content in anaphase-II by separation of sister chromatids to opposite poles. Therefore, each of the four daughter cells formed by the end of meiosis would have C DNA content.
If the G2 cell with 4C DNA enters mitosis, separation of sister chromatids to opposite poles in anaphase would reduce the DNA content. Therefore, each of the two daughter cells formed by the end of mitosis would have 2C DNA content.
Three levels of structure, however some proteins are made up of multiple polypeptide chains.
Answer:
True
Explanation:
Gregor Mendel worked with pea plant (Pisium sativum) and one of the genes he closely observed was the one coding for seed colour.
He crossed a yellow seeded pea plant (YY) with a green seeded one (yy). These parent plants are referred to as PUREBRED PARENTS. He realized that the resulting offsprings called F1 generation were all Yellow seeded, which is in accordance with Mendel's law of dominance and uniformity (expression of a dominant allele in a gene)
A significant observation was that the F1 offsprings were genetically mixed or heterozygous i.e. their genotype consisted of two different alleles (Yy).
This concept explained that, in a gene, an allele is capable of masking the expression of another. The allele that masks or is expressed is the DOMINANT allele while the allele being masked is called RECESSIVE allele.
In this case, the yellow seeded pea plant is dominant over the green seeded pea plant (recessive).
Mendel provided proof that an allele can be present but masked when he crossed two heterozygous F1 plants to produce F2 offsprings (3 yellow, 1 green).
