Macromolecules their significance types and other things

science

1. Introduction to Macromolecules L arge molecules………subunits called monomers. L inked together through chemical bonds……….larger, more complex structure. C arbohydrates, lipids, proteins, and nucleic acids. U nique properties and functions that are essential for life. Carbohydrates: Carbon, hydrogen, and oxygen atoms, P rimarily used as a source of energy in the body. S imple sugars, such as glucose, or complex carbohydrates, such as starch and cellulose. Lipids : Hy drophobic molecules (fats, oils, and waxes). They are primarily used for energy storage, insulation, and as structural components of cell membranes H ave a higher ratio of hydrogen to oxygen compared to carbohydrates. Proteins : A mino acids, wide range of biological processes. A s enzymes, transport molecules, antibodies, and structural components of cells and tissues. Complex three-dimensional structure that is crucial for their function. Nucleic acids: for storing and transmitting genetic information. DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA : Genetic instructions for the development and functioning of all living organisms, RNA : Protein synthesis. M acromolecules : essential for the structure and function of living organisms. Energy, store and transmit genetic information, and perform a wide range of biological processes necessary for life.

2. Classification of Carbohydrates Monosaccharides : S implest form and cannot be further hydrolyzed into smaller units. G lucose , fructose , and galactose . Disaccharides : Formed by the condensation of two monosaccharide units. Sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose). Polysaccharides : Complex carbohydrates composed of long chains of monosaccharide units. They can be further classified into two types: a. Homopolysaccharides : S ingle type of monosaccharide unit. starch (composed of glucose units) and cellulose (also composed of glucose units). b. Heteropolysaccharides : Different types of monosaccharide units. glycosaminoglycans (composed of repeating units of different monosaccharides) and peptidoglycans (found in bacterial cell walls).

3. Role of Monosaccharides Energy Source : G lucose , for cells. T hrough cellular respiration to produce ATP, the energy currency of cells. Building Blocks : F or disaccharides (two monosaccharides joined together) and polysaccharides (long chains of monosaccharides). Various functions, including energy storage (e.g., glycogen in animals, starch in plants) and structural support (e.g., cellulose in plant cell walls). Cell Signaling : R ibose and deoxyribose , nucleotides, building blocks of DNA and RNA. Play crucial roles in cell signaling, genetic information storage, and protein synthesis. Membrane Components : G lycolipids and glycoproteins , to cell recognition, cell adhesion, and cell signaling processes. Precursors for Biosynthesis : C onverted into other molecules through various metabolic pathways. For example, glucose can be converted into amino acids, fatty acids, and nucleotides, which are essential for the synthesis of proteins, lipids, and nucleic acids, respectively.

4. Role of Oligosaccharides Cell-cell recognition : Recognition markers, facilitating cell-cell communication and interaction. Glycoprotein and glycolipid modification : glycoproteins and glycolipids to a ffect the structure, stability, and function of the molecules. For example, oligosaccharides on the surface of glycoproteins can act as recognition sites for other molecules, such as hormones or antibodies. Prebiotic effects : fructooligosaccharides (FOS) and galactooligosaccharides (GOS), are resistant to digestion in the human gastrointestinal tract. Stimulate the growth and activity of beneficial bacteria in the gut, promoting a healthy gut microbiota and providing various health benefits. Signal molecules : S ignaling molecules in intercellular communication. C ytokinins are involved in plant growth and development, chitin oligosaccharides, can induce defense responses in plants against pathogens. Structural components : Structural components of certain molecules. Chitin forms the exoskeleton of arthropods and the cell walls of fungi . Chondroitin sulfate , a glycosaminoglycan composed of repeating disaccharide units, provides structural support to connective tissues in animals.

5. Role of Polysaccharides Energy storage and metabolism : G lycogen and starch, serve as storage forms of glucose in animals and plants, respectively. They can be broken down into glucose molecules to provide energy when needed. Oligosaccharides also play a role in carbohydrate metabolism, such as in the breakdown and synthesis of polysaccharides. Structural support: Cellulose and chitin provide structural support to plant cell walls and the exoskeletons of insects and crustaceans, respectively. Form strong, rigid structures that help maintain the shape and integrity of these organisms. Lubrication and protection: H yaluronic acid and mucins provide lubrication and protection to various tissues and organs. F orm a gel-like substance that helps reduce friction between tissues and protective barrier against pathogens and mechanical damage. Water retention : Hemicellulose and pectin , absorb and retain water. Important property in maintaining the hydration and structural integrity of plant cell walls. Dietary fiber : Cellulose , hemicellulose , and pectin dietary fiber. They are not digested by human enzymes, but they play a crucial role in maintaining digestive health by promoting regular bowel movements and providing a source of nourishment for beneficial gut bacteria.

6. Carbohydrates as information carrier molecules I n various biological processes R ole of carbohydrates in cell-cell communication and recognition O n the surface of cells, known as glycoproteins or glycolipids , M arkers ….cells to recognize and interact with each other. A re involved in processes such as immune response , tissue development , and cell adhesion . C rucial role in the immune system , r eceptors that can recognize specific carbohydrate structures on the surface of pathogens, such as bacteria or viruses. This recognition triggers an immune response and helps the body to identify and eliminate harmful invaders. In the storage and transmission of genetic information . In the form of nucleic acids, such as DNA and RNA, carbohydrates ( ribose and deoxyribose ) are essential components of the genetic code. Carry the instructions for protein synthesis and play a vital role in the transmission of hereditary information from one generation to the next.

7. Organisms Contain a Variety of Hexose Derivatives “Hydrate of carbon." general formula of carbohydrate is C n (H 2 O) n ‐ Simple hexoses such as glucose , galactose and mannose , A number of derivatives in which a hydroxyl group in the parent compound is replaced with another substituent, or a carbon atom is oxidized to a carboxyl group.

8. Oxidation of the carbonyl C of glucose to carboxyl level produces gluconic acid; other aldoses yield other aldonic acids . Oxidation of C at the C-6 of glucose, galactose , or mannose—forms the corresponding uronic acid : glucuronic , galacturonic , or mannuronic acid.

9. nine-carbon acidic sugar N -acetylneuraminic acid (a sialic acid, but often referred to simply as “sialic acid”), a derivative of N - acetylmannosamine , is a component of many glycoproteins and glycolipids in animals.

10. The substitution of H for OH group at C-6 of L- galactose or L-mannose produces L- fucose or L- rhamnose , respectively. L- Fucose (glycoproteins and glycolipids); L- rhamnose is found in plant polysaccharides.

11. Disaccharides (such as maltose, lactose, and sucrose) consist of two monosaccharides joined covalently by an O- glycosidic bond , which is formed when a hydroxyl group of one sugar reacts with the anomeric carbon of the other.

12. Starch 1. chains are 2. branch points (every 24 to 30 residues) Amylose Amylopectin