Biomolecules - Introduction to Biomolecules

• Biomolecules are the organic compounds found in living organisms.
• They are essential for the proper functioning and survival of living beings.
• Biomolecules are composed of various elements such as carbon, hydrogen, oxygen, nitrogen, and phosphorus.
• The four main classes of biomolecules are carbohydrates, proteins, lipids, and nucleic acids.
• Carbohydrates are important sources of energy and include sugars, starches, and cellulose.
• Proteins are involved in various cellular functions and are composed of amino acids.
• Lipids are a diverse group of molecules that include fats, oils, and phospholipids.
• Nucleic acids are responsible for storing genetic information and include DNA and RNA.
• Biomolecules are interconnected and play important roles in the functioning of organisms.
• Understanding biomolecules is crucial for understanding the biochemistry of living organisms.

====== 11. Carbohydrates

• Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen atoms.
• They are the main source of energy for living organisms.
• Monosaccharides are the simplest form of carbohydrates, such as glucose, fructose, and galactose.
• Disaccharides are formed by joining two monosaccharides through a glycosidic bond, such as sucrose and lactose.
• Polysaccharides are complex carbohydrates made up of many monosaccharide units, such as starch and cellulose.

12. Proteins

• Proteins are large, complex molecules composed of amino acids.
• They have various functions in living organisms, including enzymes, structural components, and antibodies.
• Amino acids are the building blocks of proteins and are connected by peptide bonds.
• Proteins have a unique three-dimensional structure, including primary, secondary, tertiary, and quaternary structures.
• Examples of proteins include hemoglobin, insulin, and collagen.

13. Lipids

• Lipids are hydrophobic organic molecules that are insoluble in water.
• They have various roles in living organisms, such as energy storage, insulation, and cell membrane structure.
• Fatty acids are the building blocks of lipids, and they can be saturated or unsaturated.
• Triglycerides are the most common form of lipid storage in organisms.
• Other types of lipids include phospholipids, steroids, and waxes.

14. Nucleic Acids

• Nucleic acids are the genetic material of living organisms and play a crucial role in protein synthesis.
• DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are the two main types of nucleic acids.
• DNA carries genetic information and is responsible for the inheritance of traits.
• RNA is involved in protein synthesis and other cellular functions.
• Nucleotides are the building blocks of nucleic acids and consist of a sugar, phosphate group, and nitrogenous base.

15. Carbohydrate Functions

• Carbohydrates serve as the primary energy source for all organisms.
• They provide quick and readily available energy through the process of cellular respiration.
• Carbohydrates also play a role in cell adhesion and recognition.
• Some carbohydrates function as structural components, such as cellulose in plant cell walls.
• Dietary fibers, which are complex carbohydrates, promote healthy digestion and prevent constipation.

16. Protein Functions

• Proteins have diverse functions in living organisms.
• Enzymes are proteins that catalyze biochemical reactions in cells.
• Structural proteins, such as collagen and keratin, provide support to tissues and organs.
• Antibodies are proteins produced by the immune system to fight against foreign substances.
• Transport proteins, like hemoglobin, transport oxygen and nutrients throughout the body.

17. Lipid Functions

• Lipids serve as a concentrated source of energy in living organisms.
• They play a significant role in energy storage, providing more energy per gram than carbohydrates or proteins.
• Lipids are a vital component of cell membranes, maintaining their structure and integrity.
• Some lipids serve as insulation and protection, such as adipose tissue under the skin.
• Lipids are also involved in hormone production and signaling.

18. Nucleic Acid Functions

• Nucleic acids store, transmit, and express genetic information in living organisms.
• DNA carries the instructions for building and maintaining an organism’s structure and function.
• RNA is involved in protein synthesis, where it transfers and translates the genetic code.
• Nucleic acids play a crucial role in the transmission of genetic information from one generation to the next.
• They are also involved in regulating gene expression and cell signaling processes.

19. Carbohydrate Examples

• Glucose is a monosaccharide and is the primary source of energy for most organisms.
• Fructose is a monosaccharide found in fruits and is sweeter than glucose.
• Sucrose is a disaccharide formed by combining glucose and fructose and is commonly known as table sugar.
• Lactose is a disaccharide found in milk and is broken down by the enzyme lactase.
• Starch and glycogen are polysaccharides that serve as energy storage in plants and animals, respectively.

20. Protein Examples

• Hemoglobin is a protein found in red blood cells and transports oxygen throughout the body.
• Insulin is a hormone protein that regulates blood sugar levels.
• Collagen is a structural protein found in the skin, bones, and connective tissues.
• Antibodies are proteins produced by the immune system to target and destroy foreign substances.
• Enzymes, such as amylase and pepsin, are protein catalysts that speed up biochemical reactions.

21. Lipid Examples

• Triglycerides are the most common type of lipid found in our body and are involved in energy storage.
• Phospholipids are essential components of cell membranes, forming a lipid bilayer.
• Steroids, such as cholesterol, are lipid molecules that have various functions in the body.
• Fats and oils are examples of lipids used as a source of energy in the diet.
• Waxes are lipids that provide waterproofing and protection in plants and animals.

22. Nucleic Acid Examples

• DNA (deoxyribonucleic acid) is a double-stranded nucleic acid that stores genetic information.
• RNA (ribonucleic acid) is a single-stranded nucleic acid that is involved in protein synthesis and other cellular processes.
• ATP (adenosine triphosphate) is a nucleotide that serves as the primary energy carrier in cells.
• Messenger RNA (mRNA) carries genetic information from DNA to the ribosomes in protein synthesis.
• Transfer RNA (tRNA) transfers amino acids to the ribosomes during protein synthesis.

23. Carbohydrate Structure

• Carbohydrates have a general formula of (CH2O)n, where n represents the number of carbon atoms.
• Monosaccharides have a linear or ring structure, depending on the number of carbon atoms.
• In glucose, a hexose sugar, the linear structure can form a ring structure through an intramolecular reaction.
• The ring structure can exist in two forms: alpha and beta, depending on the position of the hydroxyl group.
• Disaccharides and polysaccharides are formed by linking monosaccharides through glycosidic bonds.

24. Protein Structure

• Proteins have a hierarchical structure with primary, secondary, tertiary, and quaternary levels.
• The primary structure is the sequence of amino acids linked by peptide bonds.
• Secondary structures include alpha-helices and beta-sheets, which are formed by hydrogen bonding.
• Tertiary structure is the overall 3D shape of a protein, determined by interactions between amino acid side chains.
• Quaternary structure occurs when multiple protein subunits come together to form a functional protein.

25. Lipid Structure

• Lipids are composed of glycerol and fatty acids.
• Fatty acids have a carboxyl group at one end and a hydrocarbon chain at the other.
• Saturated fatty acids have single bonds between carbon atoms and are solid at room temperature.
• Unsaturated fatty acids have one or more double bonds between carbon atoms and are liquid at room temperature.
• Phospholipids have two fatty acid chains and a phosphate group, making them amphipathic.

26. Nucleic Acid Structure

• Nucleic acids are composed of nucleotides.
• Nucleotides consist of a sugar (ribose or deoxyribose), a phosphate group, and a nitrogenous base (adenine, guanine, cytosine, or thymine/uracil).
• DNA is a double helix structure, with two antiparallel strands held together by hydrogen bonds between the nitrogenous bases.
• RNA is usually single-stranded, but it can fold into various secondary structures.
• The base pairing rules for DNA are adenine with thymine and guanine with cytosine, while in RNA, adenine pairs with uracil.

27. Carbohydrate Reactions

• Carbohydrates undergo various chemical reactions, such as oxidation, reduction, and hydrolysis.
• Mono- and disaccharides can undergo fermentation, producing ethanol or lactic acid.
• Carbohydrates can form glycosidic bonds with alcohols, forming glycosides.
• Under acidic conditions, monosaccharides can undergo mutarotation, interconverting alpha and beta forms.
• Carbohydrates can also undergo condensation reactions to form larger polysaccharides.

28. Protein Reactions

• Proteins undergo various reactions, including denaturation, hydrolysis, and oxidation.
• Denaturation occurs when a protein loses its structure and function due to factors like temperature, pH, or chemicals.
• Proteins can be hydrolyzed by enzymes or acids to break peptide bonds and release individual amino acids.
• Proteins can undergo oxidation by reactive oxygen species, leading to oxidative damage.
• Proteins can also undergo post-translational modifications, such as phosphorylation or glycosylation.

29. Lipid Reactions

• Lipids can undergo reactions like hydrolysis, saponification, and esterification.
• Hydrolysis of lipids breaks the ester bond between the glycerol and fatty acids, releasing fatty acids and glycerol.
• Saponification is a reaction between lipids and bases, forming soap molecules.
• Esterification involves the reaction of fatty acids with alcohols to form esters.
• Lipids can also undergo oxidation reactions, leading to the formation of rancid odors and flavors.

30. Nucleic Acid Reactions

• Nucleic acids can undergo various reactions, including replication, transcription, and translation.
• Replication is the process of DNA synthesis, where each strand serves as a template to create a complementary strand.
• Transcription is the synthesis of RNA from a DNA template, producing mRNA, tRNA, or rRNA.
• Translation is the process of protein synthesis, where mRNA is translated into an amino acid sequence by ribosomes and tRNA.
• Nucleic acids can also undergo mutation, which is a change in the genetic sequence.