Biological macromolecules are large molecules essential for life. Cells build them from smaller organic molecules and break them down when needed. This lesson explains the four major classes of macromolecules and the reactions that join or separate their building blocks.
The four major classes of biological macromolecules are carbohydrates, lipids, proteins, and nucleic acids. They perform many different functions and together make up most of a cell’s dry mass. Water, by contrast, makes up most of a cell’s total mass.
All flashcards
What are the four major biological macromolecule classes?
Carbohydrates, lipids, proteins, and nucleic acids. They are important components of cells and perform a wide range of functions.
What is the difference between a monomer and a polymer?
A monomer is a smaller molecular building block. A polymer is a larger molecule formed when multiple units are joined, often through covalent bonds.
How does dehydration synthesis join monomers?
A hydrogen from one monomer and a hydroxyl group from another combine to form water. The monomers form a covalent bond as water is released.
How does hydrolysis break a polymer?
Hydrolysis adds a water molecule across a covalent bond. The water splits, with a hydrogen added to one product and a hydroxyl group added to the other.
How do digestive enzymes support nutrient absorption?
Specific enzymes hydrolyze food macromolecules into smaller molecules that can be absorbed by cells. Examples include amylase for carbohydrates, proteases for proteins, and lipases for lipids.
Quiz questions
Which set lists the four major classes of biological macromolecules?Answer: Carbohydrates, lipids, proteins, and nucleic acids.
Which statement describes biological macromolecules and cell mass?Answer: They make up most of a cell's dry mass.
What is a general effect of enzymes on chemical reactions?Answer: They speed reactions by catalyzing them.
What does enzyme selectivity mean?Answer: An enzyme acts on particular molecules or types of bonds.
Which substance contributes to protein digestion in the stomach alongside proteases?Answer: Hydrochloric acid.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.