Biochemistry Overview Quiz

Principles of Biochemistry

• Biochemistry is the study of chemical substances and vital processes in living organisms.
• Topics covered include DNA replication and transcription, enzymes and cofactors, ATP, and energy production.

Introduction to Biochemistry

• Cosmetic products often claim to influence biochemical skin processes.
• Some products claim to supply compounds that decline with aging, others to enhance or decrease cellular organelle activities.
• A thorough understanding of biochemistry is crucial to appreciate the proposed mechanisms of action.

Definition of Biochemistry

• Biochemistry is the study of the chemical substances and vital processes occurring in living organisms.

Structure of an Animal Cell

• Includes a diagram showing organelles like the mitochondria, ribosomes, Golgi complex, plasma membrane, nucleus (with nucleolus and nuclear pores), endoplasmic reticulum (rough and smooth), peroxisome, and secretory vesicles.
• A link is provided for more detailed explanations for each cellular part.
• Human cells are complex bioreactors and perform all required processes for survival, growth and reproduction.

Biomolecules - Carbohydrates

• Carbohydrates are divided into monosaccharides, disaccharides, oligosaccharides, and polysaccharides.
• They serve as a primary energy source for the body and are stored as glycogen in the liver and muscles.
• Carbohydrates are water-soluble.

Biomolecules - Lipids

• Lipids are organic molecules primarily composed of mostly hydrophobic chemical moieties, such as fatty acids, sterols.
• Major types of lipids include triglycerides, phospholipids, and ceramides.
• Sterols like cholesterol, testosterone, and estrogen are also lipids.

Biomolecules - Amino Acids, Peptides, and Proteins

• There are 21 different types of amino acids, 9 essential (need to be obtained from diet).
• Amino acids have an amine group, carboxylic acid group, and a variable R-group.
• They form proteins via peptide bonds.
• Proteins have a variety of structures (primary, secondary, tertiary, quaternary).

Biomolecules - Other Small Molecules

• ATP, hormones (e.g., cAMP, NO, hydrocortisone), vitamins (co-factors essential in biological processes and can't be synthesized by the human cells), and minerals are covered.

Biomolecules - Nucleic Acids

• DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are nucleic acids.
• The structural unit is the nucleotide.
• Nucleotides consist of a phosphate group, a pentose sugar (5-carbon), and a nitrogenous base.

The Nitrogenous Bases

• There are 5 different nitrogen containing bases: Adenine (A), Thymine (T), Cytosine (C), Guanine (G), and Uracil (U).
• A and G are large two-ringed bases (purines).
• C, T, and U are smaller, single-ringed bases (pyrimidines).

DNA Structure

• DNA is double-stranded forming a double helix.
• The two strands are joined by hydrogen bonds between complementary base pairs (A with T, C with G).
• Alternating sugar and phosphate molecules form the backbone of each DNA strand.
• Sugar in DNA is deoxyribose.
• Nucleotides are joined via phosphodiester linkages.

RNA Structure

• RNA is single-stranded.
• The sugar in RNA is ribose.
• Bases in RNA are A, U, C, and G.
• There are three main types of RNA: tRNA, rRNA, and mRNA.

Summary: DNA vs RNA

• DNA is the genetic material, directing protein synthesis & self-replicating; located in the nucleus.
• RNA carries out genetic instructions; found in the cytoplasm; involved in protein synthesis.
• Summary table of differences (Major cellular site, Major function, Sugar, Bases, Structure) is presented.

DNA → RNA → Amino Acids

• DNA is the master blueprint for protein synthesis.
• A gene is a segment of DNA that codes for a polypeptide chain.
• Information is in the sequence of bases.
• Codons consist of three bases and encode amino acids.
• Processes involved are transcription and translation.

The Central Dogma of Molecular Biology

• DNA is transcribed into RNA.
• RNA is translated into protein.

Transcription - RNA Synthesis

• DNA stays in the nucleus.
• RNA copies DNA's information and carries the "code" to the cytoplasm for protein synthesis.
• The process of copying is transcription.

Translation - Protein Synthesis

• Translation occurs in ribosomes (free or bound).
• Transfer RNA (tRNA) links mRNA to proteins/amino acids.
• tRNA recognizes codons on mRNA for specific amino acids.

Mechanism of Enzyme Activity

• Enzymes catalyze biochemical reactions by binding to substrates at their active sites.
• The enzyme-substrate complex undergoes changes forming a product.
• The product is released, leaving the enzyme free to catalyze additional reactions.

Lock & Key Theory

• Enzyme shape strongly determines the active site.
• The lock-and-key theory describes the precise fit between the enzyme's active site and the substrate.

Factors Affecting Enzyme Activity

• Temperature: Optimal temperature range; enzymes denature outside the range.
• pH: Optimal pH range; changes in pH alter enzyme shape.
• Substrate concentration: increasing the substrate increases the rate of enzyme catalyzed reactions until it reaches a certain threshold.
• Enzyme concentration: increasing the enzyme concentration increases the rate until a certain threshold.
• Inhibition: substances that alter or stop enzyme activity. Inhibitors can be reversible or irreversible.

Enzyme Cofactors

• Many enzymes require cofactors (coenzymes or metal ions) for activity.
• Table with a list of cofactors and corresponding enzymes.

Enzymes and Collagen Synthesis

• Collagen synthesis involves enzymes to regulate collagen production.
• Necessary elements for collagen synthesis are listed.

ATP and Energy Production

• Adenosine Triphosphate (ATP) is the main energy currency in the body.
• Energy from food is captured and stored in ATP bonds.
• ATP has a molecular weight of 507 Da and is water soluble.

Cellular Respiration

• Cellular respiration is the process for ATP production.
• Glucose is broken down to release energy for ATP synthesis.

Co-enzyme Q10 (ubiquinone)

• Ubiquinone is a fat-soluble compound found in mitochondria.
• It is a part of the electron transport chain, crucial for generating most of the body's energy.

Components of an Animal Cell

• Detailed information for Centrioles, Peroxisomes, Smooth endoplasmic Reticulum (ER), Rough ER and Golgi complex/ apparatus, Lysosomes, Vacuoles and Mitochondria is provided.
• Function and structure of each organelle presented.

Epigenetics

• Epigenome are chemical compounds marking/modifying the genome altering DNA instructions.
• Epigenetic factors can activate or deactivate genes.
• They do not change the DNA sequence but affect related proteins.
• Examples of possible epigenetic effects from products.

Gene Regulation

• Cell mechanisms are used to increase or decrease the production of RNA or proteins following specific gene products.
• Regulation occurs at several points along the pathway.
• Examples are Transcriptional control, RNA processing control, RNA transport control and translation control are presented.

Upregulation and Downregulation

• Upregulation and downregulation increase or decrease the quantity of a cellular component (RNA or protein), in response to an external stimulus.
• Example about a specific study relating to urban particulate matter and how these components downregulate various related components is presented.

Test your knowledge on essential concepts in biochemistry, including the roles of carbohydrates, lipids, and cellular processes. This quiz covers fundamental topics that are crucial for understanding biochemistry's impact on human health and its applications, such as in cosmetics. Dive into the cellular world and discover how biomolecules function uniquely in our bodies.