Within minutes of a baby’s birth, people start remarking about who this new baby resembles.’Oh, he has his dad’s chin!’ or` She’s got her mother’s eyes!’ but from where exactly do these similarities arise? Every individual has 46 chromosomes, 23 chromosomes from each parent. The chromosomes are composed of DNA. Now certain, segments of the DNA which are responsible for different traits in an individual are termed genes. Each chromosome has many genes .DNA in chromosome is copied to pass all these genes from parents to the newly growing baby. Sometimes mistake are made in copying process and resulting baby may have some defect.
(a)What is a Gene?
(b)What is the importance of variations?
(c) Give any two examples of human traits which show variations.
(d) In human what is the no of chromosomes in sperm and egg?
answer me fast it's exam time!!!
Answers
Answer:
A gene is the basic physical and functional unit of heredity. Genes are made up of DNA. Some genes act as instructions to make molecules called proteins. ... In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases
2
Genetic variationis advantageous to a population because it enables some individuals to adapt to the environment while maintaining the survival of the population. Genetic variation creates a larger pool of traits in a species so that given a novel environment, at least someone would have the trait needed to survive.
3
For example, the human eye color and skin color show variation as they are polygenic traits, meaning, they are influenced by a number of genes in combination with various environmental factors, including the temperature, and humidity of the area that they reside in.
4 both are 23 chromosome