Biomolecules and Their Building Blocks

Study Notes

Biomolecules Overview

Monomers are small molecules that bond to form polymers, the key building blocks of biological macromolecules.
Four families of biomolecules: carbohydrates, lipids, proteins, nucleic acids.
Common elements in macromolecules: carbon (C), hydrogen (H), oxygen (O); nitrogen (N) present in proteins, phosphorus (P) in nucleic acids.

Functional Groups in Biomolecules

Carboxyl Group: Can donate protons, acting as acids.
Amino Group: Found in amino acids, accepts protons, important for protein structure.
Methyl Group: Regulates gene expression.
Carbonyl Group: Functional group in carbohydrates, lipids, and proteins.
Ester Group: Present in lipids for energy storage and cell membranes.
Amide Group: Connects amino acids in proteins and is found in nucleic acids.
Phosphate Group: Vital for nucleic acid structure, found in ATP for energy transfer.
Hydroxyl Group: Present in carbohydrates, enables hydrogen bond formation.

Carbohydrates

Monosaccharides: Simple sugars, e.g., glucose, fructose; provide short-term energy.
Disaccharides: Composed of two monosaccharides, e.g., sucrose; formed through dehydration reactions.
Polysaccharides: Long chains of monosaccharides linked by covalent bonds; provide longer-lasting energy.
- Homopolysaccharides: Include starch (energy storage in plants) and cellulose (structural component of plant cell walls).
- Heteropolysaccharides: Include pectin and hyaluronic acid.

Lipids

Non-polar molecules including fats, oils, and waxes; hydrophobic in nature.
Monomer: Fatty acids, characterized by long hydrocarbon chains.
Types of fatty acids:
- Saturated Fatty Acids: Solid at room temperature; saturated with hydrogen.
- Unsaturated Fatty Acids: Liquid at room temperature; healthier, reducing heart disease risk.

Proteins

Composed of 20 amino acids, with 9 essential amino acids from diet.
Amino acids form polypeptides (proteins) by linking through peptide bonds.
Hemoglobin is the protein responsible for red blood color.

Nucleic Acids

Monomer: Nucleotide, key for energy transfer (e.g., ATP).
DNA and RNA functions: Store genetic information, self-replication, and catalytic properties.
RNA was the first macromolecule identified in protobionts.

Energy Storage

Glycogen: Polysaccharide that serves as a key energy reserve in animals.

Origin of Biomolecules

Early Earth conditions may have favored the spontaneous formation of organic molecules.
Miller Experiment: First experimental test for prebiotic synthesis, simulating early Earth conditions.
Four Stage Hypothesis:
- Production of nucleotides and amino acids before life.
- Polymerization of nucleotides to RNA/DNA and amino acids to proteins.
- Enclosure of polymers in membranes.
- Membrane-enclosed polymers gaining cellular properties.
Oparin Hypothesis: Proposed the concept of primordial soup, where organic molecules arose spontaneously.

The Prebiotic Soup Theory

Organic molecules accumulated slowly in the ocean, possibly sparked by lightning as the energy source for the beginning of life.

Description

Explore the fundamental concepts of biomolecules, including their monomeric building blocks and functional groups. This quiz covers the four major types of biomolecules—carbohydrates, lipids, proteins, and nucleic acids—and their elemental compositions. Test your knowledge on the essential roles these molecules play in living organisms.