CHE 476 Chapter 1

The Foundations of Biochemistry

High Complexity Organization

Living organisms are composed of numerous and diverse molecules organized into intricate structures that perform specialized functions.

Energy Transformation and Usage

Organisms extract energy from their environment (e.g., through photosynthesis or metabolism) to build and maintain their structures and perform work.

Dynamic and Coordinated Interactions

Cellular components interact in a coordinated manner to sustain life processes.

Sensory and Responsive Capabilities

Organisms can sense environmental changes and respond accordingly to maintain homeostasis.

Precise Self-Replication with Evolutionary Change

Organisms reproduce with high fidelity, allowing genetic information to be passed on, while also introducing variations for evolution.

Nucleus

Houses genetic material (DNA) and controls gene expression and replication.

Chromatin

DNA wrapped around proteins, facilitating its organization and function.

Chloroplast

Organelles in plant cells that conduct photosynthesis, converting solar energy into chemical energy.

Lysosomes

Contain enzymes for digesting cellular waste and recycling cellular components.

Rough Endoplasmic Reticulum

Involved in protein synthesis and modification.

Smooth Endoplasmic Reticulum

Associated with lipid synthesis and detoxification.

Golgi Apparatus

Modifies, sorts and packages proteins and lipids for secretion or delivery to other organelles.

Small Molecules

Include water, ions, and small organic molecules that participate in metabolic reactions and signaling.

Large Biomolecules

Proteins, Nucleic Acids (DNA and RNA), Carbohydrates and Lipids

Proteins

Perform a wide range of functions including catalysis (enzymes), structural support, and transport.

Nucleic Acids

DNA and RNA; store and transmit genetic information.

Carbohydrates

Provide energy and structural support.

Lipids

Form cell membranes, store energy, and act as signaling molecules.

Sunlight

Used by plants, algae, and some bacteria through photosynthesis.

Chemical Fuels

Used by animals and most bacteria through metabolic pathways.

Energy Coupling

Cells couple exergonic (energy-releasing) reactions with endergonic (energy-consuming) reactions to drive essential processes.

ATP

Adenosine Triphosphate; The primary energy currency of the cell, these to power various biological processes.

Catalysts

Enzymes; Proteins that increase the rate of biochemical reactions by lowering the activation energy without being consumed.

Metabolic Pathways

Series of enzyme-catalyzed reactions that convert substrates into products, regulated to meet the cell’s needs.

Feedback Inhibition

A regulatory mechanism where the end product of a pathways inhibits an upstream process to prevent overproduction.

DNA Structure

Double helix composed of nucleotides (adenine, thymine, cytosine, guanine) with complementary base pairing (A-T, C-G)

DNA Replication

Process by which DNA makes an exact copy of itself before cell division.

Central Dogma of Molecular Biology

Genetic information flows from DNA to RNA to protein. DNA is transcribed into RNA, which is then translated into proteins.

Mutations

Random changes in the DNA sequence that can lead to variations in traits.

Natural Selection

Process where organisms with advantageous traits are more likely to survive and reproduce, passing those traits to the next generation.

Evolution

Cumulative changes in populations over time, driven by mutation, natural selection, and genetic drift.

Domains

Bacteria, Archaea, Eukarya

Kingdoms

Bacteria, Archaea, Protista, Fungi, Plantae, Animalia

Prokaryotic Cells

Lack of a nucleus and organelles.

Eukaryotic Cells

Have a nucleus and membrane-bound organelles, more complex.

Carbon

Central element in organic molecules due to its ability to form 4 covalent bonds.

Functional Groups

Specific groupings of atoms that confer specific chemical properties.

Thermodynamics

Principles governing energy transformations. Free energy (Delta G) indicates the spontaneity of reactions.

Bioenergetics

Study of energy flow and transformation in living organisms.

Enzyme Mechanism

Enzymes bind substrates at the active site, forming an enzyme-substrate complex and lowering activation energy.

Regulation

Enzyme activity can be regulated by factors such as pH, temperature, and the presence of inhibitors or activators.

RNA World Hypothesis

Suggests that early life forms may have relied on RNA for both genetic information and catalysis,

Endosymbiotic Theory

Proposed that eukaryotic cells evolved through a symbiotic relationship between primitive eukaryotes and certain prokaryotes.

Mutation and Selection Processes

Depiction of how genetic variations arise and are selected for.

Mitochondria

Organelles that generate ATP through oxidative phosphorylation, essential for cellular energy.