Answer No 1) The correct option is a. Structures B and C are located within Structure A and code for inherited traits.
Answer No 2)
According to the most widely accepted Watson and Crick's model of DNA, the DNA comprises of two strands.
- The backbone of the DNA strands is made up of sugar-phosphate.
- The two strands are joined together by the hydrogen bonds in between the nitrogenous bases of the two strands.
<em>The two strands of the DNA are twisted around each other and form a helix. It is due to the hydrogen bonds between the two strands and their twisting that the DNA is called the double helix. </em>
Answer 3)
<em>DNA is like a recipe because the sequence of the DNA is just like the ingredients of a recipe which will be added to form the right organism. </em>
The DNA contains nitrogenous bases which will code for the traits of a particular organism with its specific characteristics just as different ingredients make up a different recipe.
<em>If DNA changes abnormally, then the traits of an organism will be affected. Serious complications might release due to the DNA changing abnormally. </em>
Answer 4)
<u><em>Differences between gene and allele</em></u>
1) Gene are a part of the chromosomes. Alleles are a part of the gene.
2) Genes determine the expression of a trait. Alleles will determine the variations which can arise in a particular trait.
3) Genes will produce a particular protein whereas alleles will produce a particular genotype.
Similarities
Both the gene and allele will determine the particular genotype and the resulting phenotype of the organism.
Answer 7)
a) Claim: Yes, genes do affect physical features of an organism.
Evidence: The genotype produces the resulting phenotype.
Reason: The genotype of an organism is determined by the particular alleles of the genes which make up the organism. The expression of these genes results in the physical characteristics of the organism.
b) Claim: Some DNA mutations are heritable, other are not.
Evidence: Those mutations might be carried along the germ line and hence can be inherited.
Reason: Some mutations are carried from the parents to the children and these mutations will be heritable. Other mutations might not be carried along the germ line and will non-heritable.
Answer 5)
Drawing of the chromosome is shown in the attachment.
A chromosome is made up of different genes. Each particular gene is made up of a allele pair. The genes comprise of a section of a DNA.
This means that all the array of chromosomes in an individual will comprise of the entire DNA.
Each cell in an organism comprises of the particular number of chromosomes which are essential for the survival of that organism, Only the sex cells contain half the number of chromosomes of the somatic cells.
