Carbon and Functional Groups

Introduction

  • Course: Biology 189: Fundamentals for Life Sciences

  • Topic: Carbon, Functional Groups, and Chemical Reactions

Learning Objectives

  • Understand the role of carbon as the backbone of organic compounds.

  • Describe hydrocarbons and organic compounds.

  • Define isomers and identify them in different compounds.

  • Identify the seven functional groups (hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, methyl, phosphate) by name, structure, and properties.

  • Learn to read shorthand chemical structures, identifying all bonded atoms and their arrangements.

General Properties of Macromolecules

  • Carbon-based with a carbon backbone.

  • Presence of functional groups, enhancing diversity and functionality.

Carbon in Organic Molecules

  • Carbon is the foundational element of organic molecules, which typically consist of carbon and hydrogen.

  • Carbon is the “backbone” of large biologically-related molecules

  • Why? Carbon atoms have 4 unpaired valence electrons (can form lots of different bond configurations

Why Carbon Forms the Backbone

  • Carbon's tetravalence allows it to form four bonds with different atoms.

  • Capable of creating combinations of single, double, and triple bonds.

  • Catenation: Bonding of carbon atoms occurs due to high bond strength, small atomic size, and moderate electronegativity. (can catenate form chains and rings with itself)

Diversity in Organic Compounds

  • Carbons can be arranged in a linear structure or ring structures.

  • Examples:

    • C8H18 (Octane)

    • C2H6O (Ethanol)

    • C6H12O6 (Glucose)

Shapes of Organic Compounds

  • Length: Varies in carbon chain length.

  • Branching: Carbons can branch in various configurations.

  • Double bond position: Affects structure and properties.

  • Presence of rings: Can alter molecule stability and functionality.

Simplest Organic Compounds

  • Hydrocarbons: Organic compounds made solely of carbon and hydrogen.

  • Examples: Methane, Propane, Benzene, Octane

  • Characteristics: Hydrophobic and release significant energy when broken down.

Isomers

  • Isomers: Molecules with the same chemical formula but with different arrangement of atoms

  • Example: C6H12O6 can exist in various forms (e.g., glucose).

Functional Groups of Macromolecules

  • Functional Group: Chemical group that has specific properties (attached to carbon skeleton of compound)

  • Functional groups impart unique properties:

    • Ethane: Nonpolar

    • Ethanol: Polar, dissolves in water due to -OH group

    • Propanoic acid: Acidic, dissolves in water

Hydroxyl Group

  • Hydro- Hydrogen Oxyl-Oxygen

  • Properties:

    • Polar

    • Hydrophilic (forms w water)

  • Found in:

    • Alcohols

    • Monosaccharide sugars

Carbonyl Group

  • Carbo- Carbon Nyl- Oxygen

  • Properties:

    • Polar

    • Hydrophilic

  • Found in:

    • Sugars and other molecules

  • Types:

    • Ketone: Carbonyl group located between two carbons

    • Aldehyde: Carbonyl group at the end of a carbon chain

Carboxyl Group

  • Structure: O=C-OH; -COOH

  • Properties:

    • Polar

    • Acidic (donates H+ ions)

    • Hydrophilic

  • Found in:

    • Carboxylic acids (e.g., acetic acid)

Amino Group

  • Structure: -NH2

  • Properties:

    • Polar

    • Basic (accepts H+ ions)

    • Hydrophilic

  • Found in:

    • Amines (e.g., glycine)

Sulfhydryl Group

  • Structure: -SH (also written as HS-)

  • Properties:

    • Polar

    • Hydrophilic

  • Role:

    • Involved in forming disulfide bridges in proteins

    • Example: Cysteine

Methyl Group

  • Structure: -CH3

  • Properties:

    • Nonpolar

    • Hydrophobic

    • Example: 5-Methyl cytidine

Phosphate Group

  • Structure: Contains negatively charged phosphate.

  • Reacts with water to release energy.

  • Important in molecules like ATP (adenosine triphosphate).

  • Charged

  • Polar

  • Hydrophilic

Adenosine Triphosphate (ATP)

  • ATP is a pivotal organic molecule that provides energy for cellular activities.

  • Emphasizes the importance of understanding ATP in biological processes.

Hormones and Functional Groups

  • Hormones provide males and females with unique secondary sexual characteristics.

  • Similar base structure but differ in functional groups, which determine their properties.

Drugs and Functional Groups

  • Examples of opioids:

    • Codeine

    • Morphine

    • Heroin

    • Oxycodone

    • Fentanyl (synthetic, 100x more potent than morphine)

    • Naloxone (used for reversing overdoses)

Chemical Reactions

  • Overview of chemical reactions: convert reactants into products.

  • Central to creating biological molecules in cells.

In-Class Question 1

  • Which functional group is polar and acts as a base?

    • A) Sulfhydryl

    • B) Carboxyl

    • C) Amino

    • D) Carbonyl

    • E) Hydroxyl

In-Class Question 2

  • Identify the missing functional group in the provided molecule:

    • A) Hydroxyl

    • B) Carbonyl

    • C) Carboxyl

    • D) Amino

In-Class Question 3

  • Identify the functional groups present in given molecules, excluding methyl groups.

In-Class Question 4

  • Analyze Atenolol, a common beta blocker used for high blood pressure.

Chemical Shorthand

  • Atenolol illustration:

    • Kekulé structure: All atoms and bonds drawn out.

    • Bond-line structure: Simplified, showing only essential bonds.

Vocabulary

  • Key terms to know:

    • Carbon

    • Phosphate group

    • Organic compounds

    • Chemical reaction

    • Hydrocarbon

    • Reactant

    • Isomers

    • Product

    • Functional group

    • Hydroxyl group

    • Carbonyl group

    • Carboxyl group

    • Amino group

    • Sulfhydryl group

    • Methyl group