Key Points

Objects around us are categorized into living and non-living based on specific characteristics they exhibit, helping us understand the world.

Living beings share common characteristics: movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, and eventual death.

Animals move from one place to another, while plants show specific movements like opening of flowers, bending towards light, or closing leaves when touched.

All living beings grow in size and require food (nutrition) for their proper growth, development, and energy needs.

Respiration is the process where living beings take in and let out air; plants respire through tiny pores called stomata on their leaves.

Living beings remove waste products from their bodies, a process called excretion, such as sweat and urine in animals or water droplets on plant leaves.

Living beings react to changes in their surroundings, known as stimuli; for example, a touch-me-not plant folds its leaves when it is touched.

Reproduction is the process by which living beings produce new ones of their own kind, which is necessary for the continuity of life on Earth.

Seeds require essential conditions such as adequate water, air, and suitable light or dark conditions to germinate and develop into a sprout.

Plant roots generally grow downwards towards gravity, while shoots grow upwards and often bend towards a light source, demonstrating specific movements.

A plant's life cycle progresses from seed germination to a mature plant that produces flowers, fruits, and new seeds, which then restart the cycle.

Mosquitoes undergo four distinct life stages: egg, larva, pupa, and adult, with larvae and pupae developing in stagnant water.

Mosquito larvae and pupae require air from the water surface; covering stagnant water with kerosene oil can prevent them from breathing and disrupt their life cycle.

Frogs have a life cycle that includes eggs (spawn), tadpoles, froglets, and adult frogs, demonstrating significant changes in form and habitat.

Animals like mosquitoes and frogs exhibit metamorphosis, which involves significant changes in appearance, body shape, and structure during their various life cycle stages.

Indian scientist Jagadish Chandra Bose invented the crescograph to measure plant growth and demonstrated that plants can sense and respond to various stimuli.