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Updated Mar 17, 2026

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Water and Biological Molecules: An Overview

Ffion

@ffion_lm

Water might seem ordinary, but it's actually one of the... Show more

WATER

Functions of water
1) Water is a reactant in loads of important chemical reactions, including hydrolysis reactions
2) Water is a solv

Water: The Ultimate Life Molecule

Water's structure is surprisingly simple yet brilliant. Each water molecule contains one oxygen atom bonded to two hydrogen atoms through shared electrons (covalent bonds). But here's where it gets interesting - the oxygen atom is a bit greedy and pulls those shared electrons towards itself.

This electron-hogging creates a polar molecule. The oxygen side becomes slightly negative (δ-) whilst the hydrogen sides become slightly positive (δ+). Think of it like a tiny magnet with positive and negative ends.

These opposite charges create hydrogen bonds between different water molecules - the slightly positive hydrogen of one molecule attracts the slightly negative oxygen of another. It's like molecular magnetism! This attraction between water molecules is called cohesion, and at room temperature, water molecules form a structured lattice pattern.

Quick Tip: Remember that hydrogen bonds are much weaker than covalent bonds, but when millions of them work together, they give water its amazing properties.

Water's biological functions are absolutely crucial for life. It acts as a reactant in hydrolysis reactions, works as a solvent for most biological reactions in cells, and transports vital substances like glucose and oxygen around organisms. Water also helps control temperature thanks to its high specific heat capacity, and provides a stable habitat for countless organisms.

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Updated Mar 17, 2026

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1 page

Water and Biological Molecules: An Overview

Ffion

@ffion_lm

Water might seem ordinary, but it's actually one of the most remarkable molecules on Earth. Its unique structure and properties make it absolutely essential for all life, from the smallest bacteria to the largest mammals.

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Water: The Ultimate Life Molecule

Quick Tip: Remember that hydrogen bonds are much weaker than covalent bonds, but when millions of them work together, they give water its amazing properties.