The Living World

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3. MËTÅBØLÏSM

It is the sum total

of all biochemical

reactions taking

place inside a living

system. (Catabolism

+ Anabolism)

It is the defining

feature of living

organisms.

Metabolic

reactions can be

demonstrated

outside the body in

cell-free systems.

Isolated metabolic

reactions, in vitro are

not living things but

are living reactions.

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4. ÇËLLÜLÅR ØRGÅÑÏZÅTÏØÑ

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It is the defining feature of living organisms. Organisms are made up of

one or more cells. [AIPMT 2007]

5. ÇØÑSÇÏØÜSÑËSS

01

It is the ability of organisms to sense their

environment and respond to environmental stimuli

(like light, water, temperature, other organisms,

chemicals, pollutants, etc).

02

All organisms are ‘aware’ of their surroundings.

So, it is the defining property of living organisms.

03

Human is the only organism having self-

consciousness.

6. ÏÑTËRÅÇTÏØÑS



All living phenomena are due to underlying interactions.

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Living organisms are self-replicating, self-evolving and self-regulating

interactive system capable of responding to external stimuli.