Biology Chapter 3 Flashcards

Study Notes

Biological Macromolecules

Large molecules essential for life, constructed from smaller organic molecules that contain carbon.
Often include hydrogen, oxygen, nitrogen, and trace elements.

Major Classes of Biological Macromolecules

Four primary categories: carbohydrates, lipids, proteins, and nucleic acids.

Monomers

Basic building blocks or single subunits that combine to form larger structures.

Polymers

Formed when monomers link together via covalent bonds, creating larger macromolecules.

Metabolism

Encompasses all chemical processes in a living organism to maintain life, including both catabolism (breaking down) and anabolism (building up).

Dehydration Synthesis/Anabolism

Also known as condensation, this process builds polymers from monomers while releasing water as a byproduct.
Involves the combination of hydrogen from one monomer with the hydroxyl group from another, creating covalent bonds and releasing water.

Hydrolysis/Catabolism

A reaction that breaks down polymers into monomers using water.
Involves a water molecule splitting, allowing one part to gain hydrogen and the other to gain a hydroxyl group.

Reactions of Dehydration and Hydrolysis

Both reactions are catalyzed by specific enzymes and involve energy changes: dehydration builds bonds (requires energy), while hydrolysis breaks bonds (releases energy).
Each reaction is specific to its respective class of macromolecules.

Role of Electrons in Reactions

In dehydration synthesis, shared electrons between monomers form covalent bonds, stabilizing the structure while water is released.

Carbohydrates

Serve as the primary energy source for the body, classified into three subtypes: monosaccharides, disaccharides, and polysaccharides.
Follow the stoichiometric formula (CH2O)n, where the carbon, hydrogen, and oxygen ratio is 1:2:1.

Monosaccharides

Simple sugars with a common structure, primarily glucose; carbon count ranges from three to seven.
Typically end with the suffix -ose.

Disaccharides

Formed when two monosaccharides undergo a dehydration reaction, resulting in a covalent glycosidic bond.

Polysaccharides

Long chains created when multiple monosaccharides link together; examples include starch.
Typically do not react with Benedict's reagent due to a lack of free aldehyde groups.

Glucose

Chemical formula: C6H12O6; crucial as an energy source in the body.
Classified as an aldose, it is one of the isomeric monosaccharides and belongs to the hexose category.

Description

This quiz covers essential concepts from Biology Chapter 3, focusing on biological macromolecules. Learn about the four major classes of macromolecules and their importance for life. Test your knowledge of terms like monomers and their functions.