Anatomy Ch 4 Cellular Metabolism
List 3 ways that RNA differs from DNA
1. RNA is single-stranded 2. RNA nucleotides have ribose instead of deoxyribose sugar 3. In place of thymine nucleotides, RNA molecules have uracil nucleotides
State two factors that control the rate of an enzyme-catalyzed reaction
1. an increase in the enzyme concentration 2. an increase in the substrate concentration
For each glucose molecule decomposed completely by cellular respiration, up to ___ molecules of ATP can be produced. All but ___ of the ATP molecules form in the aerobic reactions
38; 2
Define cofactor
A cofactor is a separate non-protein molecule that binds to an enzyme to aid in the reaction. Usually, a cofactor is a non-organic molecule. A coenzyme is a cofactor that is an organic molecule.
Distinguish between the functions of mRNA, rRNA, and tRNA.
A messenger RNA (mRNA) molecule is a special type of RNA that is made of the complementary base sequences, necessary for the production of a protein, from the DNA molecule. Transfer RNA (tRNA) is a group of RNA molecules that bind to activated amino acids in the cytoplasm and bring them to the mRNA molecule for assembly into a protein. A tRNA molecule can bind with only one kind of amino acid. THerefore, since there are twenty different amino acids, there must be at least twenty different kinds of tRNA molecules. In protein synthesis, a ribosome, composed of ribosomal RNA (rRNA) and protein molecules, moves along with the mRNA and knits together a chain of amino acids by attaching itself to a portion of the mRNA and bonding with the complementary amino acid on a tRNA molecule. As it moves along the mRNA, it attaches each amino acid in sequence and releases the empty tRNA back into the cytoplasm
Discuss two major ways that mutations occurs
A mutation is defined as a mistake in, or damage to, the DNA strand that is not corrected and is passed on to the new cells. Mutations can occur durig replication when an incorrect nucleotide or extra nucleotides bind to the parental DNA strand. Mutations can also occur if sections of the DNA strands are deleted, misplaced, or attached to the wrong chromosome.
peptide bond
A water molecule forms, and the amino acid molecules join by a bond between a carbon and nitrogen atom. This ____ bond is holds the amino acids together.
complementary base pairs
A-T G-C
Explain the importance of ATP, and its relationship to ADP.
ATP is the primary energy-carrying molecule in the cell. It acts as a rechargeable battery for cellular processes by carrying energy in the terminal bond of the phosphate molecule and returning to recapture energy when it is used. Without ATP, the cell would die. ATP releases its energy by breaking off the third, or terminal, phosphate molecule. When this occurs, it becomes ADP (with only 2 phosphate molecules). The ADP returns to "recharge" by picking up a third phosphate molecule with energy, an the cycle repeats.
Distinguish between catabolism and anabolism
Anabolism uses energy to build large molecules from smaller ones. Catabolism releases energy by breaking large molecules into smaller ones.
purines
Adenine and Guanine and consist of two organic ring structures
Explain the relationship between genes and cellular metabolism
Building block sequences of DNA instruct the cell to assemble amino acids into proteins
Define active site
During an enzyme-catalyzed reaction, regions of the enzyme molecule, called active sites, temporarily combine with portions of the substrate, forming an enzyme-substrate complex.
Distinguish between anaerobic and aerobic phases of cellular respiration
During cellular respiration, the oxidative processes that occur in the absence of oxygen are called anaerobic respiration. The oxidative processes that require the presence of oxygen for their reactions are called aerobic respiration.
Describe the events of DNA replication
During the phase before cell reproduction an enzyme called DNA polymerase breaks the hydrogen bonds between the complimentary base pairs of the DNA molecule. As the DNA molecule splits and unwinds, new nucleotides bond with the exposed nucleotides of the parental strand and a new sugar-phosphate backbone is built. The result is two complete DNA molecules, each containing one parental strand and one daughter strand. THese DNA molecules are then separated so that each new cell receives one complete DNA molecule.
codons
Each amino acid in a protein is specified by a series of three bases in DNA and then by a series of three bases in mRNA.
Calculate the number of amino acids that a DNA sequence of 27 nucleotides encodes.
Each of the 20 different types of amino acids is represented in a DNA molecule by a triplet code, consisting of sequences of three nucleotides. Therefore, a DNA sequence of 27 nucleotides encodes for 9 amino acids.
Discuss fates of glucose other than cellular respiration
Excess glucose in cells may enter anabolic carbohydrate pathways and be linked into storage forms such as glycogen. Following a meal, when blood glucose concentration is relatively high, liver cells obtain glucose from the blood and synthesize glycogen. Between meals, when blood glucose concentration is lower, the reaction reverses, and glucose is released into the blood. Glucose can also react to form fat molecules, which are later deposited in adipose tissue.
Identify the part of a DNA molecule that encodes information
Gene
Define DNA damage response
Ifthe mutation to a DNA molecule occurs on one strand, the cell uses special enzymes called repair enzymes to clip out the defective portion and rebuild correctly.
Explain why DNA replication is essential
In order for a newly formed daughter cells to function correctly, a complete copy of the DNA molecule is required during replication to ensure that metabolism and all cell functions can be carried out
Describe the function of a ribosome in protein synthesis
In protein synthesis, a ribosome, composed of rRNA and protein molecules, moves along with the mRNA and knits together a chain of amino acids by attaching itself to a portion of the mRNA and bonding with the complementary amino acid on a tRNA molecule. As it moves along the mRNA, it attaches each amino acid in sequence and releases the empty tRNA back into the cytoplasm.
Discuss the relationship between a coenzyme and a vitamin.
Many coenzymes are composed of vitamin molecules or incorporate altered forms of vitamin molecules into their structures
polypeptide
Many peptide bonds that join in a chain
Identify the final acceptor of the electrons released in the reactions of cellular respiration
Oxygen is the final electron carrier
Define energy
The ability to do work
Explain how the oxidation of molecules inside cells differs from the burning of substances outside cells
The burning of a substance outside the cell usually requires large amounts of energy to start the reaction. This burning indiscriminately breaks all chemical bonds in the substance and releases the energy as light and heat. Oxidation inside the cell utilizes enzymes that require less activation energy, controls the by-products released, and uses certain energy capturing molecules to trap about one-half of the released energy for use elsewhere. The rest is lost as heat.
Define cellular respiration
The controlled, sequential process of oxidation and energy recapture is referred to as cellular respiration
Explain how genetic information is carried from the nucleus to the cytoplasm
The first step in delivering information from the nucleus to the cytoplasm is the synthesis of mRNA.
Distinguish between a gene and a genome
The portion of a DNA molecule that contains the genetic information for making a particular protein is called a gene. The complete set of genetic instructions in a cell constitutes the genome.
Distinguish between transcription and translation
The process by which an mRNA molecule is formed from DNA is called transcription. The synthesis of protein molecules from the mRNA is called translation
transcription
The process of copying DNA information into an RNA sequence
Define cellular respiration
The process that transfers energy from molecules such as glucose and makes it available for cellular use
Distinguish among mutations, SNPs, and copy number varients
The rare distinctions in DNA sequence that affect how we look or feel are called mutations. More common genetic variants with no detectable effects are called single nucleotide polymorphisms (SNPs). Polymorphism is a term used to describe copy number variants.
Explain the importance of a rate-limiting enzyme
The rate at which a metabolic pathway functions is often determined by a regulatory enzyme that catalyzes one if its steps
Define metabolism
The sum total of chemical reactions in the cell
Explain how an enzyme "recognizes" its substrate
This ability to identify a substrate depends upon the shape of an enzyme molecule. That is, each enzyme's polypeptide chain twists and coils into unique three-dimensional conformation that fits the particular shape of its substrate molecule.
active site
a region of the enzyme molecule that temporarily combines with a specific part of the substrate, forming an enzyme-substrate complex - during an enzyme-catalyzed reaction. This interaction strains chemical bonds in the substrate in a way that makes a particular chemical reaction require less energy to occur.
Secondary metabolites
are not essential to survival, but may provide an advantage or enhancement. Best studied in plants.
Primary metabolites
are products of metabolism essential to survival
-zym
causing to ferment: enzyme- protein that speeds up a chemical reaction without itself being consumed
mut-
change: mutation- change in genetic information
carrier molecules and enzymes extract energy and store it as ATP, releasing water and heat
citric acid cycle
anaerobic reactions
do not require oxygen
pyruvic acid molecules enter mitochondria and become acetyl CoA that enters this series of reactions
electron transport chain
catalase
enzyme found in the peroxisomes of liver and kidney cells. The substrate is hydrogen peroxide, a toxic by-product of certain metabolic reactions. This enzymes only function is to decompose hydrogen peroxide into water and oxygen, an action that helps prevent accumulation of hydrogen peroxide, which damages cells.
vitamins
essential organic molecules that human cells cannot synthesize (or may not synthesize in sufficient amounts) and therefore must come from the diet
deoxyribonucleic acid DNA
genetic material which contains the information that instructs a cell to synthesize a particular protein
Excess glucose in cells may link and be stored as
glycogen
glucose molecules are broken down into pyruvic acid
glycolysis
A cell has ___ of types of enzymes and metabolic reactions
hundreds
Intermediary metabolism
refers to the processes that obtain, release, and use energy
aerobic reactions
require oxygen
genome
the complete set of genetic instructions in a cell, including the genes as well as other sequences
The genetic code is..
the correspondence between DNA triplet and amino acid
genetic code
the correspondence between a unit of DNA information and a particular amino acid
mutations
the long process of DNA replication can result in errors, adding a different nucleotide base than the one specified to a new DNA molecule
Protein synthesis- Translation (in the Cytoplasm)
1. A ribosome binds to the mRNA near the codon at the beginning of the messenger strand. 2. a tRNA molecule that has the complementary anticodon brings its amino acid to the ribosomes 3. A second tRNA brings the next amino acid to the ribosome 4. A peptide bond forms between the two amino acids, and the first tRNA is released 5. This process repeats for each codon in the mRNA sequence as the ribosomes moves along its length, forming a chain of amino acids. 6. The growing amino acid chain folds into the unique conformation of a functional protein. 7. The completed protein molecule is released. The mRNA, ribosome, and tRNA are recycled.
List the steps of protein synthesis
1. DNA information is transcribed into mRNA as a result of complementary base pairing 2. mRNA leaves the nucleus and attaches to a ribosome 3. Translation begins as an initial tRNA anticodon recognizes its complementary mRNA codon at the start of a gene, and brings the first amino acid into position 4. Translation continues as specific tRNA molecules bring the correct amino acids to the growing polypeptide chain 5. As the ribosome moves along the mRNA, more amino acids are added 6. tRNA molecules can pick up another molecule of the same amino acid and be reused 7. At the end of the mRNA, the ribosome releases the new polypeptide chain
3 important consequences of the citric acid cycle
1. One ATP is produced directly for each citric acid molecule that goes through the cycle. 2. For each citric acid molecule, eight hydrogen atoms with high-energy electrons are transferred to the hydrogen carriers NAD+ and the related molecule FAD (flavine adenine dinucleotide): NAD+ + 2H -> NADH + H+ FAD + 2H -> FADH2 3. As the 6-carbon citric acid reacts to form the 4-carbon oxaloacetic acid, two carbon dioxide molecules are produced
Protein synthesis - Transcription (in the nucleus)
1. RNA polymerase bind to the DNA base sequence of a gene 2. This enzyme unwinds and exposes part of the DNA molecule 3. RNA polymerase moves along one strand of the exposed gene and catalyzes synthesis of an mRNA, whose nucleotides are complementary to those of the strand of the gene. 4. When RNA polymerase reaches the end of the gene, the newly formed mRNA is released. 5. The DNA rewinds and closes the double helix. 6. The mRNA passes through a pore in the nuclear envelope and enters the cytoplasm
Three phases occur during glycolysis
1. two phosphate groups are added to a glucose molecule, one at each end, in a step called phosphorylation. This step requires energy from two ATPs , which are used to "prime" the glucose so that it is activated for some of the energy-releasing reactions that will happen. 2. the 6-carbon glucose molecule is cleaved into two 3-carbon molecules 3. the electron carrier NADH is produced, ATP is synthesized, and two 3-carbon pyruvic acid molecules result
dehydration synthesis
A type of anabolic process. Joins many simple sugar molecules (monosaccharides) to form larger molecules of glycogen, which store energy in their chemical bonds. When monosaccharide units join, an --OH (hydroxyl group) from one monosaccharide molecule and an --H (hydrogen atom) from an --OH group of another is reoved. As the --H and --OH react to produce a water molecule, the monosaccharides are joined by a shared oxygen atom. As the process repeats, the molecular chain extends, forming a polysaccharide. Also links glycerol and fatty acid molecules in fat cells (adipose tissue) to form triglyceride molecules. Also build up protein molecules by joining amino acid molecules. Nucleic acids are also formed by dehydration synthesis.
phosphorylation
ADP can be converted back into ATP using energy released from cellular respiration to attach a third phosphate. ATP and ADP molecules shuttle back and forth between the energy-releasing reactions of cellular respiration and the energy-utilizing reactions of the cell.
What is the role of a cofactor?
An enzyme may be inactive until it combines with a nonprotein component called a cofactor, which helps the active site fold into its appropriate conformation or helps bind the enzymes to its substrate.
hydrolysis
An example of catabolism. Can decompose carbohydrates, lipids, and proteins. A water molecule is used for each bond that breaks. EX: Hydrolysis of a disaccharide, yields two monosaccharide molecules. The bond between the simple sugars breaks, and the water molecule supplies a hydrogen atom to one sugar molecule and a hydroxyl group to the other. Reverse of dehydration synthesis.
What type of molecule is formed by the anabolism of monosaccharides? Of glycerol and fatty acids? Of amino acids?
Anabolism of... -monosaccharides form larger molecules of glycogen (store energy in their chemical bonds) -Links glycerol and fatty acid molecules in fat cells (adipose tissue) to form triglyceride forms as 3 hydrogen atoms are removed from a glycerol molecule and an --OH group is removed from each of 3 fatty acid molecules. The result of this reaction is 3 water molecules and 1 fat molecule whose glycerol and fatty acid portions are bound by shared oxygen atoms. -When two amino acid molecules are united, an --Oh from the --COOH group of one and an --H from the --NH2 group of another are removed. A water molecule forms , and the amino acid molecules join by a bond between a carbon atom and a nitrogen atom. Peptide bonds.
Glycolysis
Both aerobic and anaerobic pathways begin with glycolysis. Means "breaking of glucose". it is a series of ten enzyme-catalyzed reactions that break down the 6-carbon glucose molecule into two 3-carbon pyruvic acid molecules. Occurs in the cytosol, and because it does not require oxygen, it is referred to as anaerobic phase of cellular respiration
What are the final products of cellular respiration?
Carbon dioxide (CO2), water, and energy. Although most of the energy is lost as heat, almost half is captured as ATP.
Explain how gene expression is controlled
Certain types of proteins called transcription factors activate certain genes, moving aside the surrounding histone proteins to expose the promoter DNA sequences that start genes.
DNA repair
DNA damage response restores the original DNA sequence
Distinguish between dehydration synthesis and hydrolysis
Dehydration synthesis is a special form of anabolism where larger molecules are formed by removing an --OH (hydroxyl group) from the end of one molecule and an --H (hydrogen atom) from the end of another. The --OH and --H combine to form H2O, and the ends of the two molecules join by sharing the remaining oxygen atom. Hydrolysis is the opposite of dehydration synthesis. In hydrolysis, a large molecule is split apart at certain point and a hydrogen atom is attached to one of the new molecules, while a hydroxyl group is attached to the other. Both of these processes can occur over and over until the original molecule is altered to the cell's needs. In short, dehydration synthesis dehydrates a molecule and hydrolysis rehydrates it.
Distinguish between dehydration synthesis and hydrolysis.
Dehydration synthesis is an anabolic process that joins many monosaccharides to form larger molecules of glycogen. Hydrolysis is a catabolic reaction which can decompose carbohydrates, lipids, and proteins.
Give examples of a dehydration synthesis reaction and a hydrolysis reaction
Dehydration synthesis joins many simple sugar molecules to form larger molecules of glycogen. Glycerol and fatty acid molecules join to form larger fat molecules. Hydrolysis of a disaccharide yields two monosaccharide molecules. Fats are broken down into glycerol and fatty acids.
Explain enzyme action in a metabolic reaction
Different types of cells carry out specialized metabolic processes, but all cells perform certain basic reactions, such as the buildup an breakdown of carbohydrates, lipids, proteins, and nucleic acids. These common reactions include hundreds of very specific chemical changes that must occur in particular sequences. Enzymes control the rate of these metabolic reactions.
List the products of the citric acid cycle
Each turn of the citric acid cycle (two turns or citric acids per glucose) produces 1 ATP directly and 2 CO2 molecules.
metabolic pathways
Enzyme-catalyzed reactions form pathways when the product of one reaction is the substrate of another reaction. Metabolic pathways lead to the synthesis or breakdown of particular biochemicals.
Explain why enzymes are important in the body.
Enzymes control the rate of thousands of chemical reactions essential to life.
List factors that can denature enzymes
Exposure to excessive heat, radiation, electricity, certain chemicals, or fluids with extreme pH values can denature the conformation of an enzyme. Many enzymes become inactive at 45C and nearly all are denatured at 55C. Some proteins denature enzymes.
How does a rate-limiting enzyme illustrate negative feedback?
For some metabolic pathways, the product inhibits the rate-limiting enzyme. This type of control is an example of negative feedback. Accumulating product inhibits the pathway, and synthesis of the product falls. When the concentration of product decreases, the inhibition lifts and more product is synthesized.
List the steps of DNA replication
Hydrogen bonds break between the complementary base pairs of the two strands. Then the strands unwind and separate, exposing unpaired bases. New nucleotides pair with exposed bases, forming hydrogen bonds. An enzyme, DNA polymerase, catalyzes this base pairing. Other enzymes then knit together the new sugar-phosphate backbone.
acetyl coenzyme A
If enough oxygen is available, the pyruvic acid generated by glycolysis can continue through the aerobic pathways. These reactions include the synthesis of acetyl coenzyme A or acetyl CoA, the citric acid cycle, and the electron transport chain.
rate-limiting enzyme
In many metabolic pathways, a regulatory enzyme that catalyzes one step sets the rate for the entire sequence of reactions. The number of molecules of such a regulatory enzyme is limited. These enzymes can become saturated when the substrate concentration exceeds a certain level. Once this happens, increasing the substrate concentration no longer affects the reaction rate. Because the enzyme does not work at high substrate concentrations, it is called a ___ ____ ____. Often the first in the series of reactions that comprises the metabolic pathway.
mutagens
Induced mutations are a response to exposure to certain chemicals or radiation called mutagens. EX: ultraviolet radiation
What are the general functions of anabolism and catabolism?
Metabolic reactions and pathways are of two types: anabolism and catabolism. Anabolism, small molecules are built up into larger ones, requiring energy. In catabolism, larger molecules are broken down into smaller ones, releasing energy. Anabolism provides all the materials a cell requires for maintenance, growth, and repair.
How does cellular oxidation differ from burning?
Oxidation of substances inside cells and the burning of substances outside them have important differences. Burning in nonliving systems (such as starting a fire in a fireplace) usually requires a great deal of energy to begin, and most of the energy released escapes as heat or light. In cells, enzymes initiate oxidation by lowering the activation energy. Also, by transferring energy to ATP, cells are able to capture almost half of the energy that is released in the form of chemical energy.
What is the role of oxygen in cellular respiration?
Oxygen acts as the final electron receptor at the end of the electron transport chain, enabling the chain to continue processing electrons and recycling NAD+.
lactic acid
Reaction regenerates NAD+, the buildup of lactic acid eventually inhibits glycolysis, and ATP production declines. The lactic acid diffuses into the blood, and when oxygen levels return to normal the liver converts the lactic acid back into pyruvic acid, which can finally enter the aerobic pathway.
Explain the functions of the electron transport chain
Special carrier molecules bring the high-energy electrons to a series of enzymes that transfer much of the remaining energy to more ATP molecules. The electrons eventually combine with hydrogen ions and an oxygen atom to form water. The function of oxygen as the final electron acceptor in this last step is why the overall process is called aerobic respiration.
messenger RNA - mRNA
The first step in delivering information from the nucleus to the cytoplasm is the synthesis of mRNA. Carries a gene's information on how to build a specific polypeptide. As it is synthesized, its nucleotides form complementary base pairs with one of the two strands of DNA that encodes a particular protein.
Describe how an enzyme interacts with its substrate?
The surface of an enzyme contains areas called active sites that will bind to a specific substrate only. When the correct substrates are attached to the active sites (called an enzyme-substrate complex), the enzyme alters the shapes of the substrates in a way that promotes the reaction. All enzymes demonstrate this specificity to its substrates. To illustrate, an enzyme-substrate complex is a like a "lock-and-key" model with this enzyme as the lock and the substrate as the key. Although many keys may fit the lock, only one type of key will make it work.
pyrimidines
Thymine and Cytosine and they have a single organic ring structure
translation
To complete protein synthesis, mRNA must leave the nucleus and associate with a ribosome. There, the mRNA is translated from the language of nucleic acids to the language of amino acids.
dipeptide
Two such peptide bonds that bind amino acids
Under what conditions does a cell produce lactic acid?
Under anaerobic conditions the electron transport chain has no oxygen, and as a result it can nolonger accept new electrons from NADH. As an alternative, NADH + H+ can give its electrons and hydrogens back to byruvic acid in a reaction that forms lactic acid.
Explain why DNA must replicate
When a cell divides, each newly formed cell must receive a copy of the entire genome so ti can synthesize the proteins necessary to build basic cellular parts and metabolize, as well as the proteins that give a cell type its distinctive features.
promoter
a DNA base sequence that begins a gene
gene
a DNA sequence that contains the information for making a particular polypeptide called a ____
Adenosine triphosphate ATP
a molecule that carries energy in a form that the cell can use. It is the primary energy-carrying molecule in a cell. Even though a cell has other energy carriers, cells quickly die without enough. Consists of 3 main parts- an adenine, ribose, and 3 phosphates in a chain. The 2nd and 3rd phosphates of ATP are attached by high-energy bonds, and the chemical energy stored in one or both high-energy bonds may be quickly transferred to another molecule in a metabolic reaction. Energy from the breakdown of ATP powers cellular work such as skeletal muscle contraction, active transport across cell membranes, secretion, and many other functions.
Electron Transport Chain
a series of enzyme complexes that pass electrons. Complexes of the electron transport chain dot the folds of the inner mitochondrial membranes, which, if stretched out, may be 45 times as long as the cell membrane in some cells. As an electron passes along the electron transport chain, it gradually loses energy. The final enzyme of the electron transport chain gives up a pair of electrons that combines with two hydrogen ions and an atom of oxygen to form a water molecule. Oxygen is the final electron "carrier". In the absence of oxygen, electrons cannot continue to pass through the electron transport chain, and the aerobic reactions of cellular respiration stop.
Distinguish the aerobic from the anaerobic reactions.
aerobic reactions, which require oxygen, and anaerobic reactions, which do not.
aer-
air: aerobic respiration- respiratory process that requires oxygen
transfer RNA - tRNA
aligns amino acids in a way that enables enzymes to bond them to each other. Consists of 70-80 nucleotides and has a complex 3D shape, somewhat like a cloverleaf. Transcribed in nucleus and then sent into the cytoplasm.
adenosine diphosphate ADP
an ATP molecule that loses its terminal (end) of phosphate becomes an ADP molecule, which has only 2 phosphates
Citric Acid Cycle
begins when a 2-carbon acetyl CoA molecule combines with a 4-carbon oxaloacetic acid molecule to form the 6-carbon citric acid and CoA. The citric acid is changed through a series of reactions back into oxaloacetic acid. The CoA can be used again to combine with acetic acid to form acetyl CoA. The cycle repeats as long as the mitochondrion receives oxygen and pyruvic acid.
cata-
down: catabolism- cellular processes that break down larger molecules into smaller ones
substrate
each enzyme is specific, acting only on a particular molecule, called its substrate
activation energy
energy needed to start a metabolic reactions
Cellular respiration requires __ and ___
glucose and oxygen
Cellular respiration occurs in three distinct, yet interconnected, series of reactions:
glycolysis, citric acid cycle, and the electron transport chain
What is the structure of DNA?
is double stranded, consisting of two polynucleotide chains. The nitrogenous bases project from the sugar-phosphate backbone of one strand and bind, or pair, by hydrogen bonding to the nitrogenous bases of the second strand.
catabolism
larger molecules are broken down into smaller ones, releasing energy
RNA - ribonucleic acid
molecules accomplish the transfer of information. They can exit the nucleus because they are single-stranded and much shorter than the DNA molecules that comprise chromosomes.
Enzymes
most are proteins that increase the rate of (catalyze) specific metabolic reactions
cofactor
nonprotein component which helps the active site fold into its appropriate conformation or helps bind the enzyme to its substrate. May be an ion of an element, such as copper, iron, or zinc, or a small organic molecule, called a coenzyme. Many coenzymes are composed of vitamin molecules or incorporate altered forms of vitamin molecules.
oxidation
process that releases the energy from the glucose, which is harnessed to power cellular metabolism. In cells, enzymes initiate oxidation by lowering the activation energy.
anabolism
small molecules are built up into larger ones, requiring energy
-strat
spread out: substrate- substance upon which an enzyme acts
ribosomal RNA - rRNA
the binding of tRNA and mRNA occurs in close association with a ribosome. A ribosome is an organelle that is a tiny particle of two unequal sized subuints composed of rRNA and protein molecules.
Energy
the capacity to change something; it is the ability to do work
What is energy?
the capacity to change something; it is the ability to do work.
anticodon
the other end of each tRNA molecule includes a specific three-nucleotide sequence, called the anticodon, unique to that type of tRNA. An anticodon bonds only to the complementary mRNA codon. In this way, the appropriate tRNA carries its amino acid to the correct place in the mRNA sequence.
Cellular respiration
the process that transfers energy from molecules such as glucose and makes it available for cellular use
sub-
under: substrate- substance upon which an enzyme acts
de-
undoing: deamination- process that removes nitrogen-containing portions of amino acid molecules
ana-
up: anabolism- cellular processes in which smaller molecules are built up into larger ones
co-
with: coenzyme- substance that units with a protein to complete the structure of an active enzyme molecule
an-
without: anaerobic respiration- respiratory process that does not require oxygen
State the products of the aerobic reactions
yield up to 36 ATP molecules per glucose