420 likes | 1.37k Vues
Anabolic Metabolism. Metabolism is the transformation of energy and matter within the body. Anabolism ~ constructive metabolism Energy IS Required (ATP) ATP~ nucleotide ~ Major energy currency. Provides substances needed for growth and repair.
E N D
Anabolic Metabolism • Metabolism is the transformation of energy and matter within the body. • Anabolism~ constructive metabolism • Energy IS Required (ATP) • ATP~ nucleotide ~ Major energy currency
Provides substances needed for growth and repair. • Occurs by dehydration synthesis~ when two smaller molecules are joined water is lost. • Polysaccharides, lipids, & proteins are constructed. Molecules join H2O lost
Catabolic Metabolism • There are different metabolic reactions. These reactions occur one after the other. • The product of one reaction is the being the next reaction. • Catabolism is a type of metabolic reaction. Anabolism is the other metabolic reaction. • Catabolism, the opposite of anabolism, is the breaking down of larger molecules into smaller ones. For example...
Hydrolysis • An example of catabolism is hydrolysis, which can decompose lipids, carbohydrates, and proteins • Hydrolysis is the opposite of dehydration synthesis because a water molecule is needed to split the carbs, lipids, and proteins. • It breaks down carbs into monosaccharide; proteins into amino acids; fats into glycerol; and nucleic acids into nucleotides. • During hydrolysis, the bond between the simple sugars break. The water molecules supply a Hydrogen atom to the sugar molecule and a hydroxyl group to the other. • This doesn’t occur automatically. Hydrolysis requires certain enzymes in order to occur.
Enzymes & Their Actions/ Metabolic Pathways • enzymes: proteins that speed up biochemical reactions. (globular proteins) • Enzymes provide the energy for metabolic actions to occur. • Each enzyme has their own area which is a “pocket-shaped gap in the molecule”. This gap is called an active site. • Substrates (reactants) ,enzyme working on a particular molecule. • Enzymes are used in small quantities b/c they are not always consumed and can be reused multiple times. • Enzymes are used to quickly convert the substrates or reactants, into products. (afterward the substrate and enzyme split which releases the enzyme and they enzyme is free to be used again.)
The enzyme catalase is helpful when cleansing a cut with hydrogen peroxide. Injured cells release catalase. Then bubbles of oxygen are released which clears the cut of debris from places that are hard to reach. • Enzyme catalysis: Substrate + Enzyme Enzyme- Product + Enzyme • Subtrate Complex • Metabolic Pathway: sequence of chemical reactions that occur in an organism. • The enzymes maybe become saturated or filled to capacity when the substrate concentration goes over a certain level. When this happens it no longer affects the reaction rate. • It is very important that the rate-limiting enzyme, (usually used in small amounts) enzyme that regulates the rate of a metabolic pathway, comes first in the sequence. If it comes later some product might accumulate and that will block the pathway and the product does not finish.
Metabolic Pathways • A rate-limiting enzyme is the 1st in a series. • A coenzyme, or cofactor, is a non-protein component that either helps the active site attain its appropriate shape or helps bind the enzyme to its substance. • Some enzymes can’t function without a “partner”. EXAMPLE: Batman & Robin • Vitamins: • provide coenzymes • are essential organic molecules that human cells can’t synthesize • must come from the diet • required by the body
FACTORS:(that alter enzymes regulation) • exposure to excessive heat • radiation • electricity • certain chemicals EX: poisons • fluids w/ extreme pH values
ATP - the Release of Chemical Energy ATP is an energy-yielding molecule that is used mainly by the mitochondrion for the cell to have energy. When the mitochondrion receives energy from an outside source, such as nutrients received from sugars (mainly glucose) and proteins, the mitochondrion breaks down these materials into simpler molecules, then reattaches them to special chemical bonds named adenosine triphosphate, which is used by the cell to perform tasks, such as the continuing breakdown of nutrients that enter the cell or for other organelles to do their functions that keep the cell alive.
Electrons are what fuel the process of ATP. Coenzymes receive and take electrons away from six-carbon molecules producing 2 three-carbon molecules. The electrons are accepted by an ion in mitochondrion called NAD+ which is then turned into G3P (glyceraldehyde-3-phosphate). The broken down sugar’s bonds are rearranged by glycolytic reaction, which produces only a small amount of ATP. A Glycolytic reaction is a weak reaction that is only capable of capturing about 2% of the available energy that is released from glucose during the ATP synthesis. After the energy is released from the ATP molecules, electrons are released from it, creating ADP molecules, which are then returned to the mitochondrion to be used again for ATP synthesis. ATP is mostly used by the cell to maintain life and to perform basic functions such as movement and mitosis, but the ATP produced by the mitochondrion is also used by the mitochondrion so that it is able to break down other nutrients taken in by the cell. (This image shows the build up and breakdown of glucose, and how ATP supplies energy and phosphates to continue the procedure ATP - the Release of Chemical Energy cont.
Anaerobic Respiration • Uses no oxygen. • Usually referred to as fermentation • C6H12O6 ---> 2C3H6O3 + 2 ATP • (glucose) (lactic acid) • One that is anaerobic is called an anaerobe. • Since oxygen is the final receptor of electrons in the electron transport chain and anaerobic has no oxygen. To over come this predicament, NADH+H+ gives its hydrogen and electrons to pyruvic acid which in turn changes to lactic acid. • This changes NADH back to NAD. When lactic acid builds up, it inhibits ATP production and is then diffused into blood stream and filtered by liver and turned into pyruvic acid. For example, when we work out we produce lactic acid and it builds up in our muscles. This makes us sore because lactic acid is toxic and bad for us.
Glycolysis • Translates to “the breaking of glucose”. • Breaks down 6 carbon glucose into two 3 carbon one. • Occurs in cytosol. • Does not need oxygen. • Three Steps: 1. - Add two phosphate groups to glucose. - requires ATP, but primes molecule for energy releasing reactions 2. - One 6 carbon glucose in split into two 3 carbon glucoses. 3. - NADH is made. - 4 ADP is turned into 4 ATP. - Pyruvic acid is made • This reaction makes hydrogen atoms and they are passed by NAD+ and transform into NADH.
Aerobic Respiration • Aerobic Respiration is the process of obtaining energy for the cell when oxygen is required. • After glycolysis, the pyruvic acid generated can proceed onto aerobic respiration; which includes the citric acid cycle and electron transport chain. • These aerobic reactions yield not only CO2 and water, but up to 36 ATP molecules per glucose. • It begins with the pyruvic acid yielded in glycolysismoving from the cytosol into the mitochondria.
Aerobic Respiration (cont.) • From there, enzymes inside the mitochondria remove 2 hydrogen atoms, a carbon atom,& 2 oxygen atoms from the pyruvic acid(C3H4O3). • This generates NADH( oxidized form of Nicotinamide adenine dinucleotide)and CO2, leaving a 2-carbon acetic acid(C2H4O2). • This acid then combines with a molecule of Coenzyme A to form acetyl CoA. • CoA then “carries” the acetic acid into the citric acid cycle.
Citric Acid Cycle • The citric acid cycle is a series of chemical reactions that oxidizes certain molecules, releasing energy. • The cycle is the first step of cellular respiration that occurs inside the mitochondria. • The body’s catabolic pathways assemble on the Citric Acid Cycle. • The cycle is the second step in cellular respiration.Through glycolysis, glucose is broken down into pryuvate. In eukaryotes, pyruvate travels to the mitochondria and is changed into acetyl-CoA and enters the citric acid cycle. • The citric acid formed changes through a series of reactions back into oxaloacetic acid.(6-carbon acid and CoA) • The cycle repeats until the mitochondrion releases oxygen and pyruvic acid (product of carbohydrate oxidation). • For every turn in the cycle, one ATP (chemical bonds of energy released from the mitochondrion) is directly produced, 8 hydrogens with high energy electrons are released , and 2 CO2 molecules are produced. • These turns release 4 carbon dioxide molecules and 16 hydrogen atoms, along with 2 more molecules of ATP.
If Oxygen is available, CAC uses oxygen in cell. Resp. One ATP produced for each cycle. First in mitoch. Produsces co2 and ATP Sends molecules of energy to electron transport chain so they can produce majority of energy in H20 Lots of enzymes needed Lots have to occur for cell. Resp. to occur correctly http://en.wikipedia.org/wiki/Image:TCA_reactions.png#file difficult Reference pg. 119 Fig. 4.9 in textbook Easier
Electron Transport Chain • Series of enzyme complexes that carry and pass electrons along from one to another. • The chain passes each electron along, gradually lowering the electrons energy level and transferring the lost energy to ATP synthase. • The final enzyme of the chain gives up a pair of electrons that combine with two hydrogen ions and an atom of oxygen to form a water molecule.
Protons are translocated across the membrane, from the matrix to the intermembrane space • Electrons are transported along the membrane, through a series of protein carriers • Oxygen is the terminal electron acceptor, combining with electrons and H+ ions to produce water • As NADH delivers more H+ and electrons into the ETS, the proton gradient increases, with H+ building up outside the inner mitochondrial membrane, and OH- inside the membrane.
Cellular Respiration is the process that releases energy from molecules such as glucose and makes it available for cellular use Occurs in 3 series of reactions: glycolysis, the citric acid cycle, and the electron transport chain -> products of these reactions include CO2, H2O, and energy (38 molecules of ATP) Includes aerobic reactions (requires oxygen) and anaerobic reactions (doesn’t require oxygen) Glycolysis- the 6-carbon sugar glucose is broken down in the cytosol into two 3-carbon pyruvic acid molecules with a net gain of 2 ATP and the release of high-energy electrons Citric Acid Cycle (Krebs Cycle)- The 3-carbon pyruvic acids generated by glycolysis enter the mitochondria. Each loses a carbon (generating CO2) and is combined with a coenzyme to form a 2-carbon acetyl coenzyme A (acetyl CoA). More high-energy electrons released
Each acetyl CoA combines with a 4-carbon oxaloacetic acid to form the 6-carbon citric acid. For each citric acid, a series of reactions removes 2 carbons (generating two CO2’s), synthesizes 1 ATP, and releases more high-energy electrons. Electron Transport Chain- the high-energy electrons still contain most of the chemical energy of the original glucose molecule. Special carrier molecules bring the high-energy electrons to a series of enzymes that convert much of the remaining energy to more ATP molecules. The other products are heat and water. Image of Cellular Respiration ->
Lipid Pathway • Lipids- organic compounds that include fats, oils, and fatlike substances such as cholesterol. • Lipids supply energy and help build structures, such as cell membranes. • Most common dietary lipids are fats called triglycerides. • Saturated fats are found in food from animals and can cause cardiovascular disease. • Unsaturated fats are found in seeds, peanut and plant oils. • Monounsaturated fats are found in olive, peanut, and canola oils and these fats are the healthiest. • Triglyceride consists of glycerol and 3 fatty acids. • Fats contain twice as much energy as proteins or carbohydrates. • The body digests fat from foods into glycerol and fatty acids, which enters catabolic pathways to provide energy. • Before triglyceride can release energy it must go through hydrolysis. • They are then transported to the blood and then to the tissues. • Some of the resulting fatty acids can then form acetyl coenzyme A by reactions called beta oxidation. • In beta oxidation fatty acids are activated and once they are activated other enzymes called fatty acid oxidases breaks them down. • This phase removes two carbon segments of fatty acid chains.
Protein Pathway Cycle: Digestion turns proteins into amino acids. Then the liver takes the amino acids through deamination which removes the nitrogen and sends it to the kidneys. Then amino acids are decomposed or transferred to several different places. Some lead to the formation of acetyl coenzyme a, or go straight to steps of citric acid cycles. If not used in cycle or captured by ATP molecules then it forms glucose, fat, or goes to other uses. The glucose comes from protein catabolism going through gluconeogenesis to be part of blood glucose. Other proteins are saved and used for structural proteins which build/ repair tissues; Enzymes which control metabolic rate, clotting factors, keratins of skin and hair, elastin and collagen of connective tissue; Hormones; or Plasma Proteins which regulate water balance and muscle components actin and myosin. Will Gleeson Blk:2
Purpose: Important because they form muscle and connective tissues, and make antibodies to fight infections. Amino Acids are used to make protein molecules as specified by DNA base sequences. Also provides energy through helping with ATP and Acetyl coenzyme A. • Sources: Come from meat, fish, eggs, milk ,poultry, and cereals. They are essential proteins (8 in adults- 10 in children) that can’t be synthesized sufficiently or at all so people must eat fish, eggs, and dairy to get them. Without all 20 proteins in the body at the same time, growth and repair can not occur. The amount of dietary protein depends on body size. • Produced: When the processes are done the products produced consist of ATP, Acetyl coenzyme A, fat, glucose, structural proteins, enzymes, hormones, plasma proteins. • Pages: Please turn to pg. 125 and 720 for reference of pathways. Will Gleeson Blk:2
Carbohydrate Storage • Metabolic pathways are connected in ways that allow • molecules to enter more than one way connected. • METABOLIC PATHWAY = Chemical reactions that occur • Inside the oranganism. • Carbohydrate Molecules from foods can enter through • Anabolic and catabolic pathways. • Anabolic - be stored or react to form some of the twenty • different amino acids. B. Catabolic - used to store energy
There is excess glucose in cells that enter anabolic carbohydrate • pathways and be linked so that they are stored and form into • glycogen. * The liver and muscles cells do that best job of storing carbohydrates *When the glucose level is low, glucose is then released into the blood.
Genetic information Chromosomes are long molecules of D.N.A and protein Mitosis passes info of D.N.A to the new cell Genetic information tells the cell how to construct proteins and what the proteins jobs are. Gene: a particular part of your D.N.A strands that contains genetic info. Because enzymes control synthesis reactions, the 4 organic molecule( lipids, carbohydrates, protein,& nucleic acids) depends on protein, therefore needs genetic info to synthesis. Genome: is the set of genetic info in a cell Not all humans have genome proteins encoded.
Genetics & D.N.A • D.N.A has 2 polynucleotide chains( double helix) bonded by hydrogen. • The base can be: • A. Adenine- 2 ring structure • B. Thymine- 1 ring structure • C. Guanine- 2 ring structure • D. Cytosine- 1 ring structure A---T C---G • This is called complementary bases. • The combination of GACT would always bond with CTGA • D.N.A is a double helix • D.N.A may be composed of billions of prs. of bases • D.N.A is found wound around complex proteins to form chromatins. • D.N.A is the identity of a person.
Genetic Code What is Genetic Code? 1. It is universal. 2. It’s made up of base triplet. 3. The common bases: 4. Genetic codes are read like a sentence. 5.Definition: The Information for synthesizing proteins that is encoded in the DNA sequence. 6. The genetic code plays an important role in protein synthesis, messenger RNA, and extremely precise and specific. Base triplet- codon C,G,A,T, U (RNA)
Applications • Protein Synthesis: • mRNA carries the information for making a protein. • The “building blocks” of proteins is amino acids. • The amino acids must align in the correct sequence. • Viruses: • Virus injects an RNA into the host cell and produces proteins of the virus. • RNA: • 64 different possibilities of codons. • Contain an anticodon- end of the sequence that is only found in RNA strands.
What is DNA? • DNA is not a single molecule, but instead consists of a pair of molecules joined by hydrogen bonds. This is called a double helix. • The strands are made of nucleotides, which are adenine (A), thymine (T), uracil (U) which is rarely found in DNA, guanine (G), and cytosine (C). They are also known as bases. These bases are attached to the carbon on one side of the sugar that the body will need. • The nucleotides usually pair up by complementary pairing. For instance, A bonds with T, G bonds with C, and vice versa. A cannot bond with C or G, nor can G bond with A or T. • DNA molecules can duplicate themselves. This is called replication, During this process, the two halves of the helix separate and a new partner is created to match each half exactly.
The base-sugar unit is called a nucleoside. A phosphoric acid unit is attached to the other side of the sugar, linking the nucleoside to the neighboring sugar. Together, the phosphoric acid unit made up of bases and sugar is called a nucleotide. (You know what those are [: )
DNA Replication DNA has to be replicated in order for the cell to synthesize the proteins necessary to build cellular parts and carry on metabolism. *DNA Replication occurs during Interphase of the Cell Cycle. By: Yadira Kawaguchi
Steps • Hydrogen bonds break between the complimentary base pairs (which are A-T and C-G). • The double-stranded structure unwinds and pulls apart exposing the unpaired nucleotide bases. • New nucleotides are paired up with the exposed nucleotides. (They form hydrogen bonds) • DNA Polymerase is an enzyme that catalyzes the bonds. • Enzymes knit together the new sugar-phosphate backbone. • From 1 strand you result with 2 strands. 1 one old one and 1 new one. http://www.ncc.gmu.edu/dna/repanim.htm
Transcription is the transfer of genetic information from DNA into RNA. abby long
Transcription happens in the cell nucleus where the DNA is because the DNA cannot leave the nucleus. (The RNA is produced in the nucleolus.) • Think of DNA as instructions to build a bicycle but they are written in Japanese. The RNA polymerase will come in and change the instructions to an understandable language. • The DNA is unzipped and the RNA polymerase (an enzyme) moves along one half of the DNA and starts the synthesis of an mRNA. • RNA does not contain thymine but instead it contains uracil which binds to adenine. • The RNA polymerase comes to the end of the DNA, the mRNA is released. • The DNA winds back up and closes. • The new mRNA then passes through a pore in the nuclear envelope and into the cytoplasm.
Overview of Protein Synthesis • Protein Synthesis as a whole, is transcription and translation working together. • In order for translation to happen, transcription has to happen first. • When transcription happens, it creates a mRNA which then leaves the nucleus and enters a ribosome. • When the mRNA successfully enters the ribosome, the final step of protein synthesis occurs, translation. • After translation has successfully occurred, it has created a polypeptide chain, which is a protein that will then go where it is needed to help another cell form and develop according to what is needs to be. ( EX. A liver cell or a skin cell)
Polymerase Chain Reaction (PCR) • *A procedure that borrows a cell’s machinery for DNA replication • *Allows researchers to make many copies of a gene • *Uses a target DNA, two types of short DNA pieces called primers, a polymerase DNA, and enzymes that replicate DNA • *Steps of PCR: • Heat is used to separate two strands of target DNA • Temp is lowered, 2 DNA primers are added by complementary base pairing to target strands • DNA polymerase & bases are added to build sequence similar to target sequence • ~New synthesized strands act as templates for next round of replication which repeats itself. • *** www.dnalc.org/ddnalc/resources/pcr.html
*The steps of PCR are completed using an automated device called a thermal cycler that controls key temp. changes Strengths: it is used to work on crucial samples of rare and short DNA sequences Weaknesses: *super sensitive to fine detail which could lead to a false positive result *it is limited in that user must know sequence to be amplified; can lead to mutations