IB Biology Topic B1.1.9 Formation of Triglycerides and Phospholipids by Condensation Reactions Revision Notes (SL/HL)

IB Biology Topic B1.1.9 Formation of Triglycerides and Phospholipids by Condensation Reactions Revision Notes (SL/HL) | RevisionDojo

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Triglycerides: Energy Storage Molecules

Glycerol: A three-carbon molecule with three hydroxyl (–OH) groups.
Fatty Acids: Long hydrocarbon chains ending in a carboxyl (–COOH) group.
1. Saturated (no C=C double bonds), monounsaturated (one double bond), or polyunsaturated(multiple double bonds).

Formation via Condensation

Each fatty acid reacts with a hydroxyl on glycerol, releasing water (H₂O) and forming an ester bond.
Glycerol can bond with three fatty acids → triglyceride (3 ester bonds, 3 H₂O molecules released).
The carboxyl and hydroxyl groups are consumed, making the resulting triglyceride hydrophobic.

Properties and Functions

Hydrophobic: Insoluble in water, forming compact droplets for energy storage.
Energy Density: Higher energy content per gram than carbohydrates.
Insulation and Protection: In animals, stored in adipose tissue to cushion organs and retain heat.

Condensation Reactions in Lipid Formation

Water Release: Each ester bond formed expels 1 H₂O molecule.
Energy Requirement: Formation typically needs energy input (e.g., from ATP) to build covalent bonds.
Covalent Bond Stability: Ester bonds provide the robust link between glycerol and fatty acids (or phosphate group).

Importance of Triglycerides and Phospholipids

Triglycerides
1. Long-Term Energy Storage: Higher energy density vs. carbohydrates.

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Triglycerides: Energy Storage Molecules

Glycerol: A three-carbon molecule with three hydroxyl (–OH) groups.
Fatty Acids: Long hydrocarbon chains ending in a carboxyl (–COOH) group.
1. Saturated (no C=C double bonds), monounsaturated (one double bond), or polyunsaturated(multiple double bonds).

Formation via Condensation

Each fatty acid reacts with a hydroxyl on glycerol, releasing water (H₂O) and forming an ester bond.
Glycerol can bond with three fatty acids → triglyceride (3 ester bonds, 3 H₂O molecules released).
The carboxyl and hydroxyl groups are consumed, making the resulting triglyceride hydrophobic.

Properties and Functions

Hydrophobic: Insoluble in water, forming compact droplets for energy storage.
Energy Density: Higher energy content per gram than carbohydrates.
Insulation and Protection: In animals, stored in adipose tissue to cushion organs and retain heat.

Condensation Reactions in Lipid Formation

Water Release: Each ester bond formed expels 1 H₂O molecule.
Energy Requirement: Formation typically needs energy input (e.g., from ATP) to build covalent bonds.
Covalent Bond Stability: Ester bonds provide the robust link between glycerol and fatty acids (or phosphate group).

Importance of Triglycerides and Phospholipids

Triglycerides
1. Long-Term Energy Storage: Higher energy density vs. carbohydrates.

Definition

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A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics

IB Biology Topic B1.1.9: Formation of Triglycerides and Phospholipids by Condensation Reactions Notes

A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics

Triglycerides: Energy Storage Molecules

Formation via Condensation

Properties and Functions

Condensation Reactions in Lipid Formation

Importance of Triglycerides and Phospholipids

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Duis aute irure dolor in reprehenderit

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Triglycerides: Energy Storage Molecules

Formation via Condensation

Properties and Functions

Condensation Reactions in Lipid Formation

Importance of Triglycerides and Phospholipids

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

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