Question

define heredity . explain the mechanism of hereditary changes

Answer 1

Transmission of characters / traits from one generation to another ie; from a parent to an offspring is called Heredity

Transmission of traits from parents to offspring through genes , the functional units of heritable material that are found within all living cell s. From his studies in the mid-19th century, Gregor Mendel derived certain basic concepts of heredity, which eventually became the foundation for the modern science of genetics . Each member of the parental generation transmits only half its genes to the offspring, and different offspring of the same parents receive different combinations of genes. Many characteristics are polygenic (i.e., influenced by more than one gene). Many genes exist in numerous variations ( allele s) throughout a population. The polygenic and multiple allelic nature of many traits gives a vast potential for variability among hereditary characteristics. While the genotype (an individual 's total hereditary makeup) determines the broad limits of features an individual may develop, the actual features that do develop (the phenotype ) are dependent on complex interactions between genes and their environment. variation .

Answer 2

Answer:

Heredity refers to the passing of traits from parents to offsprings either through asexual or sexual reproduction. Gregor Johann Mendel (1822 – 1884) was the first to carryout the study on the transmission of characteristics from the parents to the offsprings. He proposed that heredity is controlled by factors, which are now believed to be segments of chromosomes or genes.

These traits are passed on in the form of genetic information from parents to offsprings. This genetic information is stored in molecules called DNA. During the process of reproduction, the child receives genetic information from both the parents in the form of DNA. 50% genetic information is passed on from the paternal DNA whereas rest 50% information is passed on by the maternal DNA. This is why a child closely resembles its parents and has traits similar to both of them. Commonly observed heritable features are curly hair, a particular type of ear lobe, hair on ears etc

Explanation: