1.2.1.1. Examples

Carbohydrates are polyhydroxy aldehydes or ketones or compounds that yield such products upon hydrolysis.

Classification Carbohydrates are classified based on their hydrolysis behavior:

1. Monosaccharides – Cannot be hydrolysed further (e.g., glucose, fructose).
2. Oligosaccharides – Yield 2–10 monosaccharide units on hydrolysis (e.g., sucrose, lactose).
3. Polysaccharides – Yield many monosaccharides on hydrolysis (e.g., starch, cellulose).

Carbohydrates are a type of biomolecule that serve as a major energy source for living organisms. They can be classified into three categories based on how they behave during hydrolysis, which is a chemical process that breaks down these molecules into smaller units:

1. Monosaccharides are the simplest form of carbohydrates and cannot be broken down further. Examples include glucose and fructose, both are single sugar units.
2. Oligosaccharides consist of 2 to 10 monosaccharides linked together. Examples include sucrose (table sugar) and lactose (milk sugar).
3. Polysaccharides are complex carbohydrates that are made up of many monosaccharides. These include starch (used by plants for energy storage) and cellulose (which forms the cell wall of plants).

Think of carbohydrates like a building made of blocks. Monosaccharides are the individual blocks (like LEGO pieces), oligosaccharides are combinations of a few blocks stuck together, and polysaccharides are large structures built with many blocks, providing strength and stability.

Monosaccharides • Simplest sugars with the general formula Cₙ(H₂O)ₙ. • Classified as aldoses (with an aldehyde group) or ketoses (with a ketone group). Examples: • Glucose (aldohexose) • Fructose (ketohexose)

Monosaccharides are the most basic form of carbohydrates. They are simple sugars that cannot be broken down into simpler sugars. They have the general formula Cₙ(H₂O)ₙ, meaning they are composed of carbon, hydrogen, and oxygen. There are two main types of monosaccharides:

1. Aldoses have an aldehyde group and include glucose, which is one of the most important sugars in biology.
2. Ketoses have a ketone group and example is fructose. These sugars serve as fundamental building blocks for larger carbohydrates.

Imagine monosaccharides as the basic ingredients in a recipe. Just like flour or sugar can be combined in various ways to make different cakes, monosaccharides can combine to form more complex sugars, contributing to a variety of flavors and structures.

Disaccharides • Formed by glycosidic linkage between two monosaccharide units. Examples: • Sucrose = Glucose + Fructose • Lactose = Glucose + Galactose • Maltose = Glucose + Glucose

Disaccharides are formed when two monosaccharides join together through a special bond called a glycosidic linkage. This process involves the elimination of a water molecule (condensation). Some common disaccharides include:

• Sucrose: formed from glucose and fructose, commonly known as table sugar.
• Lactose: found in milk, consisting of glucose and galactose.
• Maltose: made up of two glucose units, often found in malted products.

You can think of disaccharides like a pair of friends who come together to create a new team. Just like two friends might combine their strengths to create a new group activity, these simple sugars join forces to create a new sugar with unique properties.

Polysaccharides • Long chains of monosaccharide units. Examples: • Starch – Storage carbohydrate in plants. • Cellulose – Structural component in plant cell walls. • Glycogen – Storage carbohydrate in animals.

Polysaccharides are complex carbohydrates made up of long chains of monosaccharides linked together. They serve various functions based on their structure:

• Starch: used by plants to store energy, consisting of a large number of glucose units.
• Cellulose: provides structural support in plant cell walls, making plants rigid and strong.
• Glycogen: is the storage form of glucose in animals, primarily found in liver and muscle cells.

Think of polysaccharides like a long train. Each carriage (monosaccharide) is connected to create a longer structure, which can transport energy as starch or provide stability as cellulose. Just like trains can serve different purposes, polysaccharides have varied roles in living organisms based on their composition.

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