Question

An example of a monosaccharide is ________. a. fructose b. glucose c. galactose d. all of the above

Short answer

d. all of the above

Step-by-step solution

Understanding monosaccharides

A monosaccharide is the simplest form of a carbohydrate, consisting of a single sugar unit. They are the building blocks of more complex carbohydrates like disaccharides and polysaccharides.

Evaluate option a: fructose

Fructose is a simple sugar found in fruits and honey. It is a monosaccharide, as it consists of a single sugar unit.

Evaluate option b: glucose

Glucose is a simple sugar found in various foods and is a major source of energy for organisms. It is a monosaccharide, as it consists of a single sugar unit.

Evaluate option c: galactose

Galactose is a simple sugar found in milk and dairy products. It is a monosaccharide, as it consists of a single sugar unit.

Evaluate option d: all of the above

Since all of the given options (fructose, glucose, and galactose) are examples of monosaccharides, the correct answer is "d. all of the above."

Key concepts

Simple Sugars

Simple sugars, also known as monosaccharides, are the most basic form of carbohydrates. They consist of a single sugar molecule and cannot be broken down into simpler sugars. Three common examples of simple sugars are fructose, glucose, and galactose. These sugars play essential roles in our body's energy cycles. Fructose is commonly found in fruits and honey, while glucose is a primary energy source for our cells. Galactose is often found in milk and dairy products. Simple sugars are crucial in building more complex sugars and carbohydrates.
Knowing about these simple sugars helps us understand how our bodies extract energy from different foods. Next time you're enjoying a piece of fruit or drinking a glass of milk, remember that these foods provide quick energy through these simple sugar molecules!

Carbohydrates

Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen atoms. They are one of the primary sources of energy for living organisms. Carbohydrates are classified based on their complexity into simple carbohydrates and complex carbohydrates. Simple carbohydrates include mono- and disaccharides, like the simple sugars we discussed earlier.
On the other hand, complex carbohydrates consist of polysaccharides, like starch, glycogen, and cellulose. These carbohydrates provide sustained energy as they take longer to break down in our stomachs. Carbohydrates are mainly found in foods like bread, pasta, fruits, and vegetables. Our bodies convert carbohydrates into glucose, which is then used to fuel our cells. By understanding carbohydrates, we get a better idea of how different foods can impact our energy levels, metabolism, and overall health.

Disaccharides

Disaccharides are carbohydrates composed of two monosaccharide molecules. They are a step up in complexity from simple sugars, providing more prolonged energy releases compared to monosaccharides. Some common disaccharides include:

• Sucrose: Made from glucose and fructose, commonly known as table sugar.
• Lactose: Comprised of glucose and galactose, usually found in milk and dairy products.
• Maltose: Formed from two glucose molecules, found in malted foods and beverages.

These sugars must be broken down into their monosaccharide components during digestion before our bodies can use them. Disaccharides are abundant in a typical diet and contribute to our daily energy requirements. Understanding disaccharides helps us appreciate how our body processes different sources of sugar, balancing quick energy sources with those that offer sustained energy release.

Polysaccharides

Polysaccharides are complex carbohydrates made up of long chains of monosaccharide units. They serve various functions, ranging from energy storage to providing structural support for plants. In terms of human nutrition, important polysaccharides include:

• Starch: The primary energy storage polysaccharide in plants, found in foods like potatoes, rice, and wheat.
• Glycogen: The main storage form of glucose in humans and animals, usually stored in liver and muscle tissues.
• Cellulose: Provides structural support in plant cell walls, although not digestible by humans, it's an important dietary fiber.

Polysaccharides are broken down more slowly than simple sugars, making them a more enduring energy source. By including polysaccharides in our diet, we ensure a steady and reliable energy supply. Further, the fiber from indigestible polysaccharides, such as cellulose, plays a crucial role in maintaining healthy digestive functions. Understanding polysaccharides gives insight into how complex carbohydrates influence our energy levels and digestive health.