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Living Chemistry
Biochemistry is the study of chemical substances and reactions that occur in living organisms.
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Living Chemistry
Living things are made of chemicals.
Inside cells, thousands of chemical reactions occur all the time.
These reactions help organisms:
obtain energy; grow; repair tissues; build molecules; remove wastes; respond to the environment.
Recommended for Class 9
Living Chemistry
Definition
Biochemistry is the study of chemical substances and reactions that occur in living organisms.
Formula / Key Relation
Important biological molecules include:
carbohydrates; proteins; lipids; nucleic acids; vitamins; minerals; * water.
The complete set of chemical reactions occurring in a living organism is called metabolism.
Metabolism:
`catabolism + anabolism`
Catabolism:
`complex molecules → simpler molecules`
Anabolism:
`simpler molecules → complex molecules`
Living Chemistry — Advanced
Metabolism consists broadly of:
Catabolic reactions → break larger molecules down.
Anabolic reactions → build larger molecules from smaller ones.
Living systems depend on organised reaction networks regulated by enzymes.
Common Mistakes
Common Mistakes
- Mistake
Do not assume chemical reactions only occur outside living organisms.
- Mistake
Life itself depends on continuous chemistry.
- Mistake
### Sticky Notes
- Mistake
LIVING CHEMISTRY
- Mistake
BIOCHEMISTRY
- Mistake
↓
- Mistake
Chemical reactions in life
- Mistake
Metabolism:
- Mistake
CATABOLISM → breaks down
- Mistake
ANABOLISM → builds up
- Mistake
Enzymes control reactions
Revision Zone
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Biochemistry studies chemicals and reactions in living systems, and metabolism includes both breakdown and building reactions.
Biochemistry is the chemistry of living organisms. Cells contain carbohydrates, proteins, lipids, nucleic acids and many other substances that continuously take part in chemical reactions. Together, these reactions form metabolism. Catabolic pathways break molecules down, often releasing usable energy, while anabolic pathways build larger molecules and require energy input. Enzymes regulate many of these reactions so that life processes occur efficiently.
- Definition
- Biochemistry is the chemistry of living organisms. Cells contain carbohydrates, proteins, lipids, nucleic acids and many other substances that continuously take part in chemical reactions. Together, these reactions form metabolism. Catabolic pathways break molecules down, often releasing usable energy, while anabolic pathways build larger molecules and require energy input. Enzymes regulate many of these reactions so that life processes occur efficiently.
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Practice
PQ
Q1. Define biochemistry
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Q2. Define metabolism
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Q3. What is catabolism?
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Q4. What is anabolism?
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Q5. What regulates many biological reactions?
Exam Practice
EQ
Q1. Define biochemistry
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Q2. Define metabolism
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Q3. Differentiate catabolism and anabolism
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Q4. Explain why enzymes are important
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Q5. Explain why chemistry is essential for life
School-standard facts for Matric and Intermediate. Original explanations — not copied from textbooks.