Asexual Reproduction Animals and Plant
Reproduction in organisms mitosis and meiosis
Sexual Reproduction in plants
In most the Animals male and female individuals are involve in Sexual reproduction . each individual produces gametes, male gamete is called sperm cell and female gamete is called egg, During sexual reproduction sperm unites(fuses) with female egg. male gamete and female gametes are haploid nature both unite gives diploid zygote. The Fusion of male gamete with female gamete is called fertilization.Fertilization is two types , Self Fertilization and Cross Fertilization.
Self Fertilization: observe protozoans, many invertebrates like tape warm and parasites, those not able to find pair for mating , in this animals. It occurs in bisexual animals, they produces both male and female gametes.The production of male and female gamete by single parent is called Autogamy. bisexual animals called hermaphrodite they are not generally reproduce by self fertilization usually cross fertilization.
As an evolutionary and reproductive mechanism, self-fertilization allows an isolated individual to create a local population and stabilizes desirable genetic strains, but it fails to provide a significant degree of variability within a population and thereby limits the possibilities for adaptation to environmental change.
Cross fertilization:Male gamete from one parent and female gamete from other parent. this type of fertilization is called Allogamy.
Cross Fertilization is two varieties 1. external fertilization , 2 . Internal fertilization.
1.External Fertilization: This type of fertilization observe in aquatic animals like Fishes and Amphibians. Here animals produces more number of gametes .Sperm cells are released into water ,eggs also release into water . The flagellated sperm need an aquatic environment to swim to the eggs, the eggs require water to prevent drying out. These animals release large numbers of sperm and eggs, thereby overcoming large losses of gametes in the water.
whereby the male introduces sperm inside the females reproductive tract where the eggs are fertilized. Internal fertilization is an adaption for life on land, for it reduces the loss of gametes that occurs during external fertilization. Sperms are provided with a fluid (semen) that provides an aquatic medium for the sperm to swim when inside the male's body. Mating behavior and reproductive readiness are coordinated and controlled by hormones so that sperm and egg are brought together at the appropriate time.
