BIO-Intro to macromolocules and carbs

Macromolecules

Extremely large molecules important for life.

Four categories of macromolecules

Carbohydrates, proteins, lipids (fats), and nucleic acids.

Polymer

A large molecule made of many similar subunits.

Monomer

A small subunit that can join with other subunits to form a larger molecule.

Dehydration synthesis

A reaction that joins monomers to form a polymer by removing a molecule of water.

What happens to water during dehydration synthesis?

A molecule of water is removed as each bond forms.

Hydrolysis

A reaction that breaks a polymer into smaller units by adding water.

What happens to water during hydrolysis?

A molecule of water is added to break a bond.

Carbohydrate monomer

Monosaccharide (simple sugar).

Elements in carbohydrates

Carbon, hydrogen, and oxygen.

Carbohydrate linkage

Glycosidic linkage.

Typical carbohydrate element ratio

Approximately 1 carbon : 2 hydrogen : 1 oxygen (1:2:1).

Examples of simple sugars

Glucose and fructose.

Simple carbohydrates

Monosaccharides and disaccharides; they are generally readily dissolved in water.

Complex carbohydrates

Polysaccharides, such as starch; they are generally harder to break down quickly.

What makes small carbohydrates polar?

They have hydroxyl (-OH) groups.

Hydrophilic

Water-attracting; a polar substance that interacts readily with water.

Function of simple carbohydrates

Provide immediate energy and serve as building blocks for larger molecules.

Functions of complex carbohydrates

Provide structural support and store energy.

Protein monomer

Amino acid.

Elements commonly found in proteins

Carbon, hydrogen, oxygen, and nitrogen.

Lipid (fat) monomers

Lipids do not have one true repeating monomer; many are built from glycerol and fatty acids.

Elements found mostly in lipids

Carbon and hydrogen.

Nucleic acid monomer

Nucleotide.

Parts of a nucleotide

Phosphate group, sugar, and nitrogenous base.

Examples of nucleic acids

DNA and RNA.

Polysaccharide

A carbohydrate polymer made of many sugar units.

Glycogen

Polysaccharide animals use to store excess glucose; it can be broken down when energy is needed.

Starch

Polysaccharide plants use to store excess glucose.

Foods that commonly contain starch

Potatoes, corn, and wheat.

Cellulose

The most common polysaccharide on Earth; it provides structural support in plant cell walls.

Can most animals digest cellulose?

No; cellulose is indigestible by most animals.

Chitin

A polysaccharide used in arthropod exoskeletons and in the shells of crustaceans.

Which polysaccharide stores glucose in animals?

Glycogen.

Which polysaccharide stores glucose in plants?

Starch.

Which polysaccharide supports plant cell walls?

Cellulose.

Which polysaccharide helps form arthropod exoskeletons?

Chitin.

Monosaccharide

A single sugar unit; examples include glucose and fructose.

Disaccharide

A carbohydrate made of two monosaccharides joined together.

Polysaccharide examples

Glycogen, starch, cellulose, and chitin.

What does “hydrolysis” literally involve?

Using water to split a bond.

What does “dehydration synthesis” involve?

Removing water to join units together.

How are monomers and polymers related?

Many monomers can join to form a polymer.

Why are carbohydrates useful to organisms?

They provide energy, store energy, and provide structural support.