Carbon and Functional Groups

Introduction

• Course: Biology 189: Fundamentals for Life Sciences

• Instructor: Earl Yoon

• 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