Answer:
False
Explanation:
A double-helical DNA molecule consists of two DNA strands. A DNA strand has free 5' phosphate at one end and a free hydroxyl group (OH) at its 3' end. A DNA double helix is said to be antiparallel since each end of the double helix has an exposed 5' phosphate on one strand and a free 3' hydroxyl group (OH) on the other. This means that the two DNA strands run in opposite directions. A phosphate group is always esterified to the 5' carbon of the pentose sugar; never at its 3' end.
The correct answer would be D, because the ending result for mitosis is 2 diploid cells, meaning the number chromosomes are the same. While in meiosis, the ending result is 4 haploid cells. Because the cell was divided twice, this means that each daughter cell has half of the number of chromosomes.
Answer:
Crossing two chickens heterozygous for the trait feather color, when brown feathers are dominant over red feathers, will produce offspring with brown and red feathers in a brown:red phenotypic ratio of 3:1.
Explanation:
Knowing that in chickens brown feathers are the expression of the dominant allele (B) and the recessive allele is red (b), crossing two heterozygous individuals (Bb) will result in offspring that are likely to have brown or red feathers.
The cross can be represented by a Punnett Square:
<u>Bb X Bb cross
</u>
alleles B b
B BB Bb
b Bb bb
Where the result is:
<u>Genotypes</u>:
<u>Phenotypes</u>:
- Brown feathers, 75%
- Red feathers, 25%.
In this case, the probability of having brown or red feathers is 3:1.