16.Fertilization: The process of fusion of male and female gametes 17.Parthenogenesis: The development of egg to new form without fertilization. E.g Rotifers, Honey bees, Turkey birds etc. 18.External fertilization: When fertilization takes place outside the body of organisms. E.g Frog and Bony Fishes. 19.Internal Fertilization: When fertilization takes place inside the body of female organisms. E.g Female human. 20.Zygote: The product of fusion of male and female gametes. The development of embryo from the zygote. 21.Embryogenesis: Egg laying animals e.g Fishes, Reptiles, Amphibians and Birds. 22.Oviparous: 23.Viviparous: The organism which gives birth of young one. E.g Mammals excepting Echidra ( oviparous mammals) 24.Pericarp: Protective wall of fruit, sometimes pericarp is differentiated into mesocarp and Endocarp. 25.Clone: Organisms which are morphologically and Genetically identical with eah other. B. Important Notes: 1.Life Span Period from birth till natural death.Every organism lives only for certain period of time Eg Elephant 60 -90 years, Fruit fly 4-5 weeks. Life span of mayfly is one day.Life span of Man is 100 years.Life span of parrot is 140 years Life span of a banyan tree is 200 yearsLife span of Tortoises is 100- 150 years PHASES OF LIFE SPAN. Juvenile phase: The phase of growth before reproductive maturity. Reproductive phase: Reproductive maturity. Senescent phase: Phase between reproductive maturity and death. 2.Reproduction: The biological process by which an organism produces its own kind to maintain the race. Reproduction enables the continuity of species generation after generation. Types of Reproduction: Asexual reproduction
16.Fertilization: The process of fusion of male and female gametes 17.Parthenogenesis: The development of egg to new form without fertilization. E.g Rotifers, Honey bees, Turkey birds etc. 18.External fertilization: When fertilization takes place outside the body of organisms. E.g Frog and Bony Fishes. 19.Internal Fertilization: When fertilization takes place inside the body of female organisms. E.g Female human. 20.Zygote: The product of fusion of male and female gametes. 21.Embryogenesis: The development of embryo from the zygote. 22.Oviparous: Egg laying animals e.g Fishes, Reptiles, Amphibians and Birds. 23.Viviparous: The organism which gives birth of young one. E.g Mammals excepting Echidra ( oviparous mammals) 24.Pericarp: Protective wall of fruit, sometimes pericarp is differentiated into mesocarp and Endocarp. 25.Clone: Organisms which are morphologically and Genetically identical with eah other. B. Important Notes: 1.Life Span Period from birth till natural death.Every organism lives only for certain period of time Eg Elephant 60 -90 years, Fruit fly 4-5 weeks. Life span of mayfly is one day.Life span of Man is 100 years.Life span of parrot is 140 years Life span of a banyan tree is 200 yearsLife span of Tortoises is 100- 150 years PHASES OF LIFE SPAN. Juvenile phase: The phase of growth before reproductive maturity. Reproductive phase: Reproductive maturity. Senescent phase: Phase between reproductive maturity and death. 2.Reproduction: The biological process by which an organism produces its own kind to maintain the race. Reproduction enables the continuity of species generation after generation. Types of Reproduction: Asexual reproduction
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