Cell Theory PDF

CAPITOL UNIVERSITY COLLEGE OF HEALTH SCIENCES MC2 BIOCHEMISTRY Transcribed by: De La Torre, Hana Jaye B. spontaneous generation in his experiments about rotting meat. CHAPTER...

CAPITOL UNIVERSITY COLLEGE OF HEALTH SCIENCES MC2 BIOCHEMISTRY Transcribed by: De La Torre, Hana Jaye B. spontaneous generation in his experiments about rotting meat. CHAPTER 1: CELL THEORY LOUIS PASTEUR-GERM THEORY The Cell Theory Grew Out Of The Work Of Many Scientists And Improvements In The 1856-Used the microscope to Microscope. discover that tiny, one- celled (eukaryotic) yeast created alcoholic ROBERT HOOKE fermentation and that other one-celled, rod-shaped organism He was the first person to look at (prokaryotic bacteria) caused cells and named them. He looked at beverages to spoil. cork cells which are not living. Pasteur (1864) designed a flask It is the bark of a tree so they are experiment that disproved the idea dead plant cells. They are small of spontaneous generation once and squares and they reminded him of for all! the small rooms in a monastery called cells PROKARYOTIC AND EUKARYOTIC CELLS ANTON VAN LEEUWENHOEK There are two cell types: eukaryotic Credited with improving the cells and prokaryotic cells. microscope. (Zacharias Janssen is credited with discovering/creating microscope). Leeuwenhoek’s EUKARYOTIC CELLS microscope could magnify 200x the human eye! Today’s microscopes have a nucleus (true nucleus) which can magnify up to 1500! contains DNA that forms many chromosomes. MATTHIAS SCHLEIDEN Eukaryotic cells have membrane-bound organelles. was a German botanist (scientist who studies plants.) PROKARYOTIC CELLS He found that the plant parts he examined were made of cells. He Prokaryotic cells do not have a made the generalization that all nucleus. plants were made of cells. Prokaryotic cells do not have membrane-bound organelles, but THEODOR SCHWANN they do have some organelles like ribosomes. Studied animals. His microscopic Prokaryotic cells do not have a investigations of animal parts led nucleus, but they have one him to generalize that all animals are chromosome and “extra” circular made of cells pieces of DNA called “plasmids”. After looking at Schleiden’s work ,he further proposed that all organisms are made of cells. CELL THEORY RUDOLF VIRCHOW is one of the basic principles of biology. German doctor that said that new CREDIT FOR THE FORMULATION OF plant cells arise only from existing THIS THEORY IS GIVEN TO: plant cells, and new animal cells German scientists Theodor arise only from existing animal cells. Schwann Building off the work of Redi (1668) (1810–1882), Matthias Schleiden who disproved the idea of (1804–1881), and Rudolph Virchow  CHAPTER 2: CARBOHYDRATES CELL THEORY STATES THAT: METABOLISM All living organisms are composed of cells. They may be unicellular or multicellular. The cell is the basic unit of life. Cells arise from pre-existing cells. (They are not derived from spontaneous generation.) MODERN CELL THEORY STATES THAT: Energy flow occurs within cells. Carbohydrate Metabolism - is a Heredity information (DNA) is fundamental biochemical process that passed on from cell to cell. ensures a constant supply of energy to All cells have the same basic living cells. The most important chemical composition. carbohydrate is glucose, which can be broken down via glycolysis, enter into the In addition to the cell theory, the gene Kreb's cycle and oxidative theory, evolution, homeostasis, and the phosphorylation to generate ATP. laws of thermodynamics form the basic principles that are the foundation for the Carbohydrates are defined as biomolecules study of life. containing a group of naturally occurring carbonyl compounds (aldehydes or CELL PROCESSES ketones) and several hydroxyl groups. It consists of carbon (C), hydrogen (H), and CELL PROCESSES: ENDOCYTOSIS AND oxygen (O) atoms, usually with a EXOCYTOSIS hydrogen-oxygen atom ratio of 2:1 (as in water). It’s represented with the empirical Cells perform a number of important formula Cm(H2O)n (where m and n may or processes that are necessary for the may not be different) or (CH2O)n. survival of an organism. Cells undergo the complex process of CLASSIFICATION OF CARBOHYDRATES cellular respiration in order to obtain energy stored in the nutrients Four major groups based on the degree consumed. of polymerization: CELL PROCESSES: CELL MIGRATION MONOSACCHARIDES is a process that is vital for the - Building blocks development of tissues and organs. - Simple sugars Cell movement is also required for - Colorless mitosis and cytokinesis to occur. - crystalline solids that are soluble Cell migration is made possible by in water and insoluble in a interactions between motor enzymes nonpolar solvent. and cytoskeleton microtubules. - Dihydroxyacetone and D- and L-glyceraldehydes are the CELL PROCESSES: DNA REPLICATION smallest monosaccharides – here, AND PROTEIN SYNTHESIS n=3. The cell process of DNA replication Examples: is an important function that is - Aldolases containing the needed for several processes aldehyde group (the functional including chromosome synthesis group with the structure, R-CHO) and cell division to occur. DNA - Ketoses containing ketone transcription and RNA translation groups functional group with the make the process of protein structure synthesis possible.  FUNCTIONS OF MONOSACCHARIDES FUNCTIONS OF DISACCHARIDES - Glucose (C6H12O6) is an important - Sucrose is a product of source of energy in humans and photosynthesis, which functions as a plants. Plants synthesize glucose major source of using carbon dioxide and water, carbon and energy in plants. which in turn is used for their energy - Lactose is a major source of energy requirements. They store the excess in animals. glucose as starch which humans - Maltose is an important intermediate and herbivores consume. in starch and glycogen digestion. - The presence of galactose is in milk - Trehalose is an essential energy sugar (lactose), and fructose in fruits source for insects. and honey makes these foods - Cellobiose is essential in sweet. carbohydrate metabolism. - Ribose is a structural element of - Gentiobiose is a constituent of plant nucleic acids and some coenzymes. glycosides and some - Mannose is a constituent of polysaccharides. mucoproteins and glycoproteins required for the proper functioning of the OLIGOSACCHARIDES Body. - yield 3 to 10 molecules of the same DISACCHARIDES or different monosaccharides on hydrolysis - consist of two sugar units. - are classified as trisaccharides, - The covalent bond formed between tetrasaccharides, pentasaccharides, the two sugar molecules is known as and so on. a glycosidic bond or glycosidic - Cn(H2O)n-2, and that of tetrasaccharides is Cn(H2O)n-3, and Disaccharides can be classified into two so on. groups based on their ability to undergo - normally present as glycans. oxidation-reduction reactions - They are linked to either lipids or amino acid side chains in proteins by REDUCING SUGAR N- or O-glycosidic bonds known as glycolipids or glycoproteins. A disaccharide in which the reducing sugar has a free hemiacetal unit serving as a The glycosidic bonds are formed in the reducing aldehyde group. Examples include process of glycosylation, in which a maltose and cellobiose. carbohydrate is covalently attached to an organic molecule, creating structures such NON-REDUCING SUGAR as glycoproteins and glycolipids. Disaccharides that do not have a free N-LINKED OLIGOSACCHARIDES: hemiacetal because they bond through an - It involves the attachment of acetal linkage between their anomeric oligosaccharides to asparagine via a centers. Examples are sucrose and beta linkage to the amine nitrogen of trehalose. the side chain. In eukaryotes, this process occurs at the membrane of the endoplasmic reticulum. Whereas  in prokaryotes, it occurs at the heteropolysaccharides. plasma membrane. HOMOPOLYSACCHARIDES O-LINKED OLIGOSACCHARIDES - are composed of repeating units of - It involves the attachment of only one type of monomer. oligosaccharides to threonine or - Examples: cellulose, chitin, serine on the hydroxyl group of the starches (amylose and amylopectin), side chain. It occurs in the Golgi glycogen, and xylans. apparatus, where monosaccharide - Based on functional role these units are added to a complete compounds are classified into polypeptide chain. structural polysaccharides and storage polysaccharides. FUNCTIONS OF OLIGOSACCHARIDES - Cellulose is a linear, unbranched polymer of glucose units joined by - Glycoproteins are carbohydrates beta 1-4 linkages. It’s one of the attached to proteins involved in most abundant organic compounds critical functions such as antigenicity, in the biosphere. solubility, and resistance to - Chitin is a linear, long-chain polymer proteases. Glycoproteins are of N-acetyl-D-glucosamine (a relevant as cell-surface receptors, derivative of glucose) residues/units, cell-adhesion molecules, joined by beta 1-4 glycosidic immunoglobulins, and tumor linkages. It’s the second most antigens. abundant natural biopolymer after - Glycolipids are carbohydrates cellulose. attached to lipids that are important - Starch is made of repeating units of for cell recognition and modulate D-glucose that are joined together membrane proteins that act as by alpha-linkages. It’s one of the receptors. most abundant polysaccharides - Cells produce specific found in plants and is composed of a carbohydrate-binding proteins mixture of amylose (15-20%) and known as lectins, which mediate amylopectin (80-85%). cell adhesion with oligosaccharides. - Oligosaccharides are a component HETEROPOLYSACCHARIDES of fiber from plant tissues. - composed of two or more repeating POLYSACCHARIDES units of different types of monomers. - Examples: glycosaminoglycans, agarose, and peptidoglycans. In natural systems, they are linked to proteins, lipids, and peptides. Glycosaminoglycans (GAG) are negatively charged unbranched heteropolysaccharides. They are composed of repeating units of disaccharides with the general structural formula n. Amino acids - a chain of more than 10 like N-acetylglucosamine or carbohydrates joined together N-acetylgalactosamine and uronic acid (like through glycosidic bond formation. glucuronic acid) are normally present in the - They are ubiquitous and mainly GAG structure. involved in the structural or storage functions of organisms. - They are also known as glycans. Based on the type of monosaccharides involved in the formation of polysaccharide structures, they are classified into two groups: homopolysaccharides and  - Peptidoglycan protects bacterial cells from bursting by counteracting the osmotic pressure of the cytoplasm. HYALURONIC ACIDS are an essential component of the vitreous humor in the eye and synovial fluid (a lubricant fluid present in the body’s joints). It’s also involved in other developmental processes like tumor metastasis, angiogenesis, and blood coagulation. - Peptidoglycan is a heteropolymer HEPARIN of alternating units of acts as a natural anticoagulant that prevents N-acetylglucosamine (NAG) and blood from clotting. N-acetylmuramic acids (NAM), linked together by KERATAN beta-1,4-glycosidic linkage. sulfate is present in the cornea, cartilage, - Agarose is a polysaccharide and bones. In joints, it acts as a cushion to composed of repeating units of a absorb mechanical disaccharide, agarobiose, consisting shocks. of D-galactose and 3,6-anhydro-L-galactopyranose. CHONDROITIN is an essential component of cartilage that FUNCTIONS OF POLYSACCHARIDES provides resistance against compression. STRUCTURAL POLYSACCHARIDE: DERMATAN SULFATE They provide mechanical stability to cells, is involved in wound repair, blood organs, and organisms. Examples include coagulation regulation, infection responses, chitin and cellulose. Chitin is involved in the and cardiovascular synthesis of fungal cell walls, while cellulose diseases. is an important constituent of diet for ruminants. DIGESTION AND ABSORPTION OF CARBOHYDRATES STORAGE POLYSACCHARIDES: 1. Mouth - the enzyme salivary They are carbohydrate storage reserves amylase begins breaking down that release sugar monomers when required starch into shorter polysaccharides by the body. Examples include starch, glycogen, and inulin. Starch stores energy 2. Stomach - Salivary amylase is for plants, and in animals, it is catalyzed by inactivated and no further the enzyme amylase (found in saliva) to carbohydrate digestion occurs fulfill the energy requirement. Glycogen is a polysaccharide food reserve of animals, 3. Small Intestine - Majority of starch bacteria, and fungi, while inulin is a storage digestion and breakdown of reserve in plants. disaccharides occur here. The enzyme pancreatic amylase breaks AGAROSE down starch into mono, di, and provides a supporting structure in the cell oligosaccharides. wall of marine algae. PEPTIDOGLYCAN is an essential component of bacterial cell walls. It provides strength to the cell wall and participates in binary fission during bacterial reproduction.  GLYCOGEN AND GLYCOGENOLYSIS GLYCOGEN - Storage form of glucose in animals. - Stored in the liver (6-8%) & muscle (1-2%). - Quantity more in the muscle(~250g) than liver(75g) due to higher muscle mass. - Stored as granules in the cytosol. Glycogen vs. Fat as source of energy - Fat cannot be rapidly metabolized - The first organ to receive glucose, like glycogen. fructose, and galactose is the liver - Fat cannot generate energy in the absence of oxygen. - Brain requires a continuous supply The liver takes them up and converts of glucose, which come from galactose to glucose, breaks fructose into glycogen. even smaller carbon-containing units, and - Fat cannot produce glucose. either stores glucose as glycogen or exports it back to the blood. How much glucose the GLYCOGENOLYSIS liver exports to the blood is under hormonal - occurs by a pathway distinctly control and you will soon discover that even different from the reversal glycogen the glucose itself regulates its breakdown concentrations in the blood. GLYCOGEN STORAGE DISEASE GLYCOGENESIS - A process of making a glucose to a storage Glycogen. GLYCOGENOLYSIS - A process of breaking glycogen to free glucose. - A process of breaking the bonds of MAINTAINING BLOOD GLUCOSE glycogen to have a free glucose. LEVELS: THE PANCREAS AND LIVER - Debranching of glucose –1-phosphate to form glucose Glucose regulates its levels in the blood via a process called negative feedback. Von Gierke Disease - opposing hormone called glucagon. - Occur in the absence of Glucagon-secreting cells in the glucose-6-phophatase. pancreas sense the drop in glucose and, in response, release glucagon - HEPATOMEGALY is- enlarged liver into the blood. Glucagon - HYPOGLYCEMIA is a condition in communicates to the cells in the which your blood sugar (glucose) body to stop using all the glucose. level is lower than normal More specifically, it signals the liver Hyperlipidemia means your blood to break down glycogen and release has too many lipids (or fats), such as the stored glucose into the blood, so cholesterol and triglycerides. that glucose levels stay within the - HYPERURICEMIA, is an excess of target range and all cells get the uric acid in your blood. Uric acid is needed fuel to function properly. produced during the breakdown of  purines, which are found in certain foods and are also formed by your body - GSDIII or Cori disease is - an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. GSDV or McArdle disease - is an inherited disorder caused by an inability to break down a complex sugar called glycogen in muscle cells. A lack of glycogen breakdown interferes with the function of muscle cells. - People with GSDV typically experience fatigue, muscle pain, and cramps during the first few minutes of exercise (exercise intolerance). type VI (also known as GSDVI or Hers disease) - an inherited disorder caused by an inability to break down a complex sugar called glycogen in liver cells. A lack of glycogen breakdown interferes with the normal function of the liver. Medline Plus,2020. Myoglobinuria is the presence of an excess amount of myoglobin in the urine. It is mostly caused by muscle breakdown, releasing a high amount of myoglobin in the blood. Myoglobinuria can lead to acute kidney injury. Andersen disease (GSD IV) is a rare genetic disorder of glycogen metabolism. It is caused by the deficient activity of the glycogen-branching enzyme, resulting in accumulation of abnormal glycogen in the liver, muscle, and/or other tissues. The disease is inherited as an autosomal recessive trait.