Answer:
The correct answer is - hydrogen bond.
Explanation:
Hydrogen bonding is very essential for life on earth. DNA has a double-helix structure that means it has two distinct strands in its structure and hydrogen bonds hold together the nitrogen base pairs in the middle. In absence of hydrogen bonds, DNA would have to exist as a different structure. The principal force or bonds between those two strands are Hydrogen bonds between the nitrogen bases. Adenine always makes a hydrogen bond with Thymine whereas Guanine always binds with cytosine.
Thus, the correct answer is - hydrogen bond.
The thoracic cavity is separated from the abdominopelvic cavity by the diaphragm
They seem to be complex they are rapid and tend to spread
Answer:
Cross overs can lead to formation of chromosome pairs that have no mutant allele.
Explanation:
Cross overs can lead to formation of chromosome pairs that have no mutant allele.
For example -
Suppose "X" is a mutant allele and "x" is a mutant free allele.
Now when two homologous chromosomes contains a single mutant allele in different parts of the chromosome are crossed the following offspring are produced
X x
X XX Xx
x Xx xx
"xx" is a mutant free genotype.
Thus, crossing over can create a single mutation-free chromosome
The answer of the first question is double fertilization !!! I don't get the second question so.... comment if you have that question !!!
