Biology
Distinguish between the following pairs:
(i) Monohybrid and Dihybrid cross
(ii) Genotype and Phenotype
(iii) Character and Trait
(iv) Dominant and Recessive Allele
(v) Autosomes and Sex chromosomes
Answer
(i) Difference between Monohybrid and Dihybrid cross:
| Monohybrid Cross | Dihybrid cross |
|---|---|
| Single feature is taken into consideration | Two features are taken into consideration. |
| Phenotypic ratio in second generation is 3:1 | Phenotypic ratio in second generation is 9:3:3:1 |
| Genotypic ratio is 1:2:1 | Genotypic ratio obtained is very complex |
(ii) Difference between Genotype and Phenotype:
| Genotype | Phenotype |
|---|---|
| Set of genes present in any organism is known as its genotype. | Characters expressed or physical appearance of characters is called phenotype. |
| Can be determined by genotyping method. | Can be determined by observation. |
| It is formed by expressed and unexpressed genes. | It consists of only expressed genes. |
(iii) Difference between Character and Trait:
| Character | Trait |
|---|---|
| Any inheritable feature of an organism is a character. | The alternative forms of a character are called traits. |
| For example, flower colour is a character. | For example, within the character of flower colour, specific traits will be red, blue, or white flower colour. |
(iv) Difference between Dominant and Recessive Allele:
| Dominant Allele | Recessive Allele |
|---|---|
| The gene that expresses itself phenotypically. | The gene that remains unexpressed in presence of dominant allele. |
| Expresses in homozygous as well as heterozygous condition. | Expresses only in homozygous condition. |
| Represented by capital letters. | Represented by small letters. |
(v) Difference between Autosomes and Sex chromosomes:
| Autosomes | Sex chromosomes |
|---|---|
| Autosomes are chromosomes that determine the general body features. | Sex chromosomes determine the sex of an organism. |
| Humans have 22 pairs of autosomes. | Humans have 1 pair sex chromosomes. |
Related Questions
Who discovered for the first time the basic principles of genetics?
Give the common and scientific names of the organism on which Gregor Mendel had worked.
Write two characters of pea pod with their alternative traits.
Which one of the following is the phenotypic monohybrid ratio in F2 generation?
- 3 : 1
- 1 : 2 : 1
- 2 : 2
- 1 : 3