Efnisyfirlit

• Cover image
• Title page
• Table of Contents
• Copyright
• Preface
• Faculty resources
• Part One: Principles of Molecular Structure and Function
• Chapter 1: Introduction to Biomolecules
• Water is the solvent of life
• Water contains hydronium ions and hydroxyl ions
• Ionizable groups are characterized by their pk values
• The blood pH is tightly regulated
• Acidosis and alkalosis are common in clinical practice
• Bonds are formed by reactions between functional groups
• Isomeric forms are common in biomolecules
• Properties of biomolecules are determined by their noncovalent interactions
• Triglycerides consist of fatty acids and glycerol
• Monosaccharides are polyalcohols with a keto group or an aldehyde group
• Monosaccharides form ring structures
• Complex carbohydrates are formed by glycosidic bonds
• Polypeptides are formed from amino acids
• Nucleic acids are formed from nucleotides
• Most biomolecules are polymers
• Summary
• Questions
• Chapter 2: Introduction to Protein Structure
• Amino acids are zwitterions
• Amino acid side chains form many noncovalent interactions
• Peptide bonds and disulfide bonds form the primary structure of proteins
• Proteins can fold themselves into many shapes
• α-helix and β-pleated sheet are the most common secondary structures in proteins
• Globular proteins have a hydrophobic core
• Proteins lose their biological activities when their higher-order structure is destroyed
• The solubility of proteins depends on pH and salt concentration
• Proteins absorb ultraviolet radiation
• Proteins can be separated by their charge or their molecular weight
• Abnormal protein aggregates can cause disease
• Neurodegenerative diseases are caused by protein aggregates
• Protein misfolding can be contagious
• Summary
• Questions
• Chapter 3: Oxygen-Binding Proteins: Hemoglobin and Myoglobin
• The heme group is the oxygen-binding site of hemoglobin and myoglobin
• Myoglobin is a tightly packed globular protein
• Red blood cells are specialized for oxygen transport
• The hemoglobins are tetrameric proteins
• Oxygenated and deoxygenated hemoglobin have different quaternary structures
• Oxygen binding to hemoglobin is cooperative
• 2,3-Bisphosphoglycerate is a negative allosteric effector of oxygen binding to hemoglobin
• Fetal hemoglobin has a higher oxygen-binding affinity than does adult hemoglobin
• The Bohr effect facilitates oxygen delivery
• Most carbon dioxide is transported as bicarbonate
• Summary
• Questions
• Chapter 4: Enzymatic Reactions
• The equilibrium constant describes the equilibrium of the reaction
• The free energy change is the driving force for chemical reactions
• The standard free energy change determines the equilibrium
• Enzymes are both powerful and selective
• The substrate must bind to its enzyme before the reaction can proceed
• Rate constants are useful for describing reaction rates
• Enzymes decrease the free energy of activation
• Many enzymatic reactions can be described by michaelis-menten kinetics
• Km and vmax can be determined graphically
• Substrate half-life can be determined for first-order but not zero-order reactions
• Kcat/km predicts the enzyme activity at low substrate concentration
• Allosteric enzymes do not conform to michaelis-menten kinetics
• Enzyme activity depends on temperature and pH
• Different types of reversible enzyme inhibition can be distinguished kinetically
• Covalent modification can inhibit enzymes irreversibly
• Enzymes stabilize the transition state
• Chymotrypsin forms a transient covalent bond during catalysis
• Summary
• Questions
• Chapter 5: Coenzymes
• Enzymes are classified according to their reaction type
• Adenosine triphosphate has two energy-rich bonds
• ATP donates phosphate in phosphorylation reactions
• ATP hydrolysis drives endergonic reactions
• Cells always try to maintain a high energy charge
• Dehydrogenase reactions require specialized coenzymes
• Coenzyme a activates organic acids
• S-adenosyl methionine donates methyl groups
• Many enzymes require a metal ion
• Summary
• Questions
• Part Two: Genetic Information: DNA, RNA, and Protein Synthesis
• Chapter 6: DNA, RNA, and Protein Synthesis
• All living organisms use DNA as their genetic databank
• DNA contains four bases
• DNA forms a double helix
• DNA can be denatured
• DNA is supercoiled
• DNA replication is semiconservative
• DNA is synthesized by DNA polymerases
• DNA polymerases have exonuclease activities
• Unwinding proteins present a single-stranded template to the DNA polymerases
• One of the new DNA strands is synthesized discontinuously
• RNA plays key roles in gene expression
• The σ subunit recognizes promoters
• DNA is faithfully copied into RNA
• Some RNAs are chemically modified after transcription
• The genetic code defines the structural relationship between mRNA and polypeptide
• Transfer RNA is the adapter molecule in protein synthesis
• Amino acids are activated by an ester bond with the 3′ terminus of the tRNA
• Many transfer RNAs recognize more than one codon
• Ribosomes are the workbenches for protein synthesis
• The initiation complex brings together ribosome, messenger RNA, and initiator tRNA
• Polypeptides grow stepwise from the amino terminus to the carboxyl terminus
• Protein synthesis is energetically expensive
• Gene expression is tightly regulated
• A repressor protein regulates transcription of the lac operon in E. coli
• Anabolic operons are repressed by the end product of the pathway
• Glucose regulates the transcription of many catabolic operons
• Transcriptional regulation depends on DNA-binding proteins
• Summary
• Questions
• Chapter 7: The Human Genome
• Chromatin consists of DNA and histones
• The nucleosome is the structural unit of chromatin
• Covalent histone modifications regulate DNA replication and transcription
• DNA methylation silences genes
• All eukaryotic chromosomes have a centromere, telomeres, and replication origins
• Telomerase is required (but not sufficient) for immortality
• Eukaryotic DNA replication requires three DNA polymerases
• Most human DNA does not code for proteins
• Gene families originate by gene duplication
• The genome contains many tandem repeats
• Some DNA sequences are copies of functional RNAs
• Many repetitive DNA sequences are (or were) mobile
• L1 elements encode a reverse transcriptase
• ALU sequences spread with the help of L1 reverse transcriptase
• Mobile elements are dangerous
• Humans have approximately 20,000 genes
• Transcriptional initiation requires general transcription factors
• Genes are surrounded by regulatory sites
• Gene expression is regulated by DNA-binding proteins
• Long noncoding RNAs play roles in gene expression
• mRNA processing starts during transcription
• Translational initiation requires many initiation factors
• mRNA processing and translation are often regulated
• Small RNA molecules inhibit gene expression
• Mitochondria have their own DNA
• Human genomes are very diverse
• Human genomes have many low-frequency copy number variations
• Summary
• Questions
• Chapter 8: Protein Targeting and Proteostasis
• A signal sequence directs polypeptides to the endoplasmic reticulum
• Glycoproteins are processed in the secretory pathway
• The endocytic pathway brings proteins into the cell
• Lysosomes are organelles of intracellular digestion
• Autophagy recycles cellular proteins and organelles
• Poorly folded proteins are either repaired or destroyed
• Ubiquitin marks proteins for destruction
• The proteostatic system protects cells from abnormal proteins
• Summary
• Questions
• Chapter 9: Introduction to Genetic Diseases
• Four types of genetic disease
• Mutations occur in the germline and in somatic cells
• Mutations are an important cause of poor health
• Small mutations lead to abnormal proteins
• Most mutations are caused by replication errors
• Mutations can be induced by radiation and chemicals
• Mismatch repair corrects replication errors
• Missing bases and abnormal bases need to be replaced
• Nucleotide excision repair removes bulky lesions
• Repair of dna double-strand breaks is difficult
• Hemoglobin genes form two gene clusters
• Many point mutations in hemoglobin genes are known
• Sickle cell disease is caused by a point mutation in the β-chain gene
• SA heterozygotes are protected from tropical malaria
• α-thalassemia is most often caused by large deletions
• Many different mutations can cause β-thalassemia
• Fetal hemoglobin protects from the effects of β-thalassemia and sickle cell disease
• Polygenic diseases have multiple genetic risk factors
• Genetic risk factors are discovered in genome-wide association studies
• Summary
• Questions
• Chapter 10: Viruses
• Viruses can replicate only in a host cell
• Bacteriophage T4 destroys its host cell
• DNA viruses substitute their own DNA for the host cell DNA
• λ phage can integrate its DNA into the host cell chromosome
• RNA viruses require an RNA-dependent RNA polymerase
• Retroviruses replicate through a DNA intermediate
• Plasmids are small “accessory chromosomes” or “symbiotic viruses” of bacteria
• Bacteria can exchange genes by transformation and transduction
• Jumping genes can change their position in the genome
• Summary
• Questions
• Chapter 11: DNA Technology
• Restriction endonucleases cut large DNA molecules into smaller fragments
• Large probes are used to detect copy number variations
• Small probes are used to detect point mutations
• Southern blotting determines the size of restriction fragments
• DNA can be amplified with the polymerase chain reaction
• PCR is used for preimplantation genetic diagnosis
• Allelic heterogeneity is the greatest challenge for molecular genetic diagnosis
• Normal polymorphisms are used as genetic markers
• Tandem repeats are used for DNA fingerprinting
• DNA microarrays can be used for genetic screening
• DNA microarrays are used for the study of gene expression
• DNA is sequenced by controlled chain termination
• Massively parallel sequencing permits cost-efficient whole-genome genetic diagnosis
• Gene therapy targets somatic cells
• Viruses are used as vectors for gene therapy
• Retroviruses can splice a transgene into the cell’s genome
• Genome editing is based on the making and healing of DNA double strand breaks
• Designer nucleases are used for genome editing
• Antisense oligonucleotides can block the expression of rogue genes
• Genes can be altered in animals
• Tissue-specific gene expression can be engineered into animals
• Human germline genome editing is technically possible
• Summary
• Questions
• Part Three: Cell and Tissue Structure
• Chapter 12: Biological Membranes
• Membranes consist of lipid and protein
• Phosphoglycerides are the most abundant membrane lipids
• Most sphingolipids are glycolipids
• Cholesterol is the most hydrophobic membrane lipid
• Membrane lipids form a bilayer
• The lipid bilayer is a two-dimensional fluid
• The lipid bilayer is a diffusion barrier
• Membranes contain integral and peripheral membrane proteins
• Membranes are asymmetrical
• Membranes are fragile
• Membrane proteins carry solutes across the lipid bilayer
• Transport against an electrochemical gradient requires metabolic energy
• Active transport consumes ATP
• Sodium cotransport brings molecules into the cell
• Summary
• Questions
• Chapter 13: The Cytoskeleton
• The erythrocyte membrane is reinforced by a spectrin network
• Keratins give strength to epithelia
• Actin filaments are formed from globular subunits
• Striated muscle contains thick and thin filaments
• Myosin is a two-headed molecule with ATPase activity
• Muscle contraction requires calcium and ATP
• The cytoskeleton of skeletal muscle is linked to the extracellular matrix
• Microtubules consist of tubulin
• Eukaryotic cilia and flagella contain a 9 + 2 array of microtubules
• Cells form specialized junctions with other cells and with the extracellular matrix
• Summary
• Questions
• Chapter 14: The Extracellular Matrix
• Collagen is the most abundant protein in the human body
• The tropocollagen molecule forms a long triple helix
• Collagen fibrils are staggered arrays of tropocollagen molecules
• Collagen is subject to extensive posttranslational processing
• Collagen metabolism is altered in aging and disease
• Many genetic defects of collagen structure and biosynthesis are known
• Elastic fibers contain elastin and fibrillin
• The amorphous ground substance contains hyaluronic acid
• Sulfated glycosaminoglycans are covalently bound to core proteins
• Cartilage contains large proteoglycan aggregates
• Proteoglycans are synthesized in the er and degraded in lysosomes
• Mucopolysaccharidoses are caused by deficiency of glycosaminoglycan-degrading enzymes
• Bone consists of calcium phosphates in a collagenous matrix
• Basement membranes contain type iv collagen, laminin, and heparan sulfate proteoglycans
• Fibronectin glues cells and collagen fibers together
• Summary
• Questions
• Part Four: Molecular Physiology
• Chapter 15: Extracellular Messengers
• Steroid hormones are made from cholesterol
• Progestins are the biosynthetic precursors of all other steroid hormones
• Thyroid hormones are synthesized from protein-bound tyrosine
• T4 becomes activated to T3 in the target tissues
• Both hypothyroidism and hyperthyroidism are common disorders
• Insulin is released together with the C-peptide
• Proopiomelanocortin forms several active products
• Angiotensin is formed from circulating angiotensinogen
• Immunoassays are used for determination of hormone levels
• Catecholamines are synthesized from tyrosine
• Indoleamines are synthesized from tryptophan
• Histamine is produced by mast cells and basophils
• Neurotransmitters are released at synapses
• Acetylcholine is the neurotransmitter of the neuromuscular junction
• There are many neurotransmitters
• Summary
• Questions
• Chapter 16: Intracellular Messengers
• Receptor-hormone interactions are noncovalent, reversible, and saturable
• Many neurotransmitter receptors are ion channels
• Steroid and thyroid hormones bind to transcription factors
• Seven-transmembrane receptors are coupled to G proteins
• Adenylate cyclase is regulated by G proteins
• Hormones can both activate and inhibit the camp cascade
• Cytoplasmic calcium is an important intracellular signal
• Phospholipase C generates two second messengers
• Both camp and calcium regulate gene transcription
• Muscle contraction and exocytosis are triggered by calcium
• Atrial natriuretic factor acts through a membrane-bound guanylate cyclase
• Nitric oxide stimulates a soluble guanylate cyclase
• cGMP is a second messenger in retinal rod cells
• Receptors for insulin and growth factors are tyrosine-specific protein kinases
• Growth factors and insulin trigger multiple signaling cascades
• Cytokine receptors use the JAK-STAT pathway
• Many receptors become desensitized after overstimulation
• Summary
• Questions
• Chapter 17: Plasma Proteins
• Plasma proteins are both synthesized and destroyed in the liver
• Albumin prevents edema
• Albumin binds many small molecules
• Some plasma proteins are specialized carriers of small molecules
• Deficiency of α1-antitrypsin causes lung emphysema
• Levels of plasma proteins are affected by many diseases
• Blood components are used for transfusions
• Blood clotting must be tightly controlled
• Platelets adhere to exposed subendothelial tissue
• Insoluble fibrin is formed from soluble fibrinogen
• Thrombin is derived from prothrombin
• Factor X can be activated by the extrinsic and intrinsic pathways
• Negative controls are necessary to prevent thrombosis
• Plasmin degrades the fibrin clot
• Heparin and vitamin K antagonists are used as anticoagulants
• Clotting factor deficiencies cause abnormal bleeding
• Tissue damage causes release of cellular enzymes into blood
• Summary
• Questions
• Chapter 18: Defense Mechanisms
• Lipophilic xenobiotics are metabolized to water-soluble products
• Cytochrome P-450 is involved in phase I metabolism
• Phase II metabolism makes xenobiotics water-soluble for excretion
• Phase III metabolism excretes xenobiotic metabolites
• Drug-metabolizing enzymes are inducible
• The innate immune system uses pattern recognition receptors
• Infection triggers inflammation
• Lymphocytes possess antigen receptors
• B Lymphocytes produce immunoglobulins
• Antibodies consist of two light chains and two heavy chains
• Different immunoglobulin classes have different properties
• Adaptive immune responses are based on clonal selection
• Immunoglobulin genes are rearranged during B-cell development
• The T-cell receptor recruits cytosolic tyrosine protein kinases
• Mediators of inflammation are produced from arachidonic acid
• Prostaglandins are synthesized in all tissues
• Prostanoids participate in many physiological processes
• Leukotrienes are produced by the lipoxygenase pathway
• Antiinflammatory drugs inhibit the synthesis of eicosanoids
• Summary
• Questions
• Chapter 19: Cellular Growth Control and Cancer
• The cell cycle is controlled at checkpoints
• Cells can be grown in culture
• Cyclins play key roles in cell cycle control
• Retinoblastoma protein guards the G1 checkpoint
• Cell proliferation is triggered by mitogens
• Mitogens regulate gene expression
• Cells can commit suicide
• Cancers are monoclonal in origin
• Cancer is caused by activation of growth-promoting genes and inactivation of growth-inhibiting genes
• Some retroviruses contain an oncogene
• Retroviruses can cause cancer by inserting themselves next to a cellular proto-oncogene
• Many oncogenes code for components of mitogenic signaling cascades
• Cancer susceptibility syndromes are caused by inherited mutations in tumor suppressor genes
• Many tumor suppressor genes are known
• Components of the cell cycle machinery are abnormal in most cancers
• DNA Damage causes either growth arrest or apoptosis
• Most spontaneous cancers are defective in p53 action
• The PI3K/protein kinase B pathway is activated in many cancers
• The products of some viral oncogenes neutralize the products of cellular tumor suppressor genes
• Tumors become more malignant through darwinian selection
• Intestinal polyps are benign lesions
• Intestinal polyps can evolve into colon cancer
• Summary
• Questions
• Part Five: Metabolism
• Chapter 20: Digestive Enzymes
• Saliva contains α-amylase and lysozyme
• Protein and fat digestion start in the stomach
• The pancreas is a factory for digestive enzymes
• Fat digestion requires bile salts
• Some digestive enzymes are anchored to the surface of the microvilli
• Poorly digestible nutrients cause flatulence
• Many digestive enzymes are released as inactive precursors
• Summary
• Questions
• Chapter 21: Introduction to Metabolic Pathways
• Alternative substrates can be oxidized in the body
• Metabolic processes are compartmentalized
• Free energy changes in metabolic pathways are additive
• Most metabolic pathways are regulated
• Feedback inhibition and feedforward stimulation are the most important regulatory principles
• Metabolism is regulated to ensure homeostasis
• Inherited enzyme deficiencies cause metabolic diseases
• Vitamin deficiencies, toxins, and endocrine disorders can disrupt metabolic pathways
• Summary
• Questions
• Chapter 22: Glycolysis, Tricarboxylic Acid Cycle, and Oxidative Phosphorylation
• Glucose uptake into the cells is regulated
• Glucose degradation begins in the cytoplasm and ends in the mitochondria
• Glycolysis begins with ATP-dependent phosphorylations
• Most glycolytic intermediates have three carbons
• Phosphofructokinase is the most important regulated enzyme of glycolysis
• Lactate is produced under anaerobic conditions
• Pyruvate is decarboxylated to acetyl-CoA in the mitochondria
• The TCA cycle produces two molecules of carbon dioxide for each acetyl residue
• Reduced coenzymes are the most important products of the TCA cycle
• Oxidative pathways are regulated by energy charge and [NADH]/[NAD+] ratio
• The TCA cycle provides a pool of metabolic intermediates
• Antiporters transport metabolites across the inner mitochondrial membrane
• The respiratory chain channels electrons from NADH and FADH2 to molecular oxygen
• The standard reduction potential is the tendency to donate electrons
• The respiratory chain contains flavoproteins, iron-sulfur proteins, cytochromes, ubiquinone, and protein-bound copper
• The respiratory chain contains large multiprotein complexes
• The respiratory chain creates a proton gradient
• The proton gradient drives ATP synthesis
• The efficiency of glucose oxidation is close to 40%
• Oxidative phosphorylation is limited by the supply of ADP
• Brown adipose tissue contains an uncoupling protein
• Mutations in mitochondrial DNA can cause disease
• Summary
• Questions
• Chapter 23: Oxygen Deficiency and Oxygen Toxicity
• Ischemia leads to infarction
• Oxidative phosphorylation is inhibited by many poisons
• Hypoxia inducible factor adjusts cell metabolism to hypoxia
• Reactive oxygen derivatives are formed during oxidative metabolism
• The respiratory chain is a major source of superoxide
• Cells have specialized enzymes to destroy reactive oxygen species
• Free radical formation is affected by energy supply and energy consumption
• Some vitamins and phytochemicals can scavEnge free radicals
• The NRF2 transcription factor coordinates defenses against reactive oxygen species
• Phagocytic cells use reactive oxygen species for intracellular killing
• Summary
• Questions
• Chapter 24: Carbohydrate Metabolism
• An adequate blood glucose level must be maintained at all times
• Gluconeogenesis bypasses the three irreversible reactions of glycolysis
• Fatty acids cannot be converted into glucose
• Glycolysis and gluconeogenesis are regulated by hormones
• Glycolysis and gluconeogenesis are fine tuned by allosteric effectors and hormone-induced enzyme phosphorylations
• Fructose-2,6-bisphosphate switches the liver from gluconeogenesis to glycolysis
• Glucokinase is regulated by two regulatory proteins
• Carbohydrate is stored as glycogen
• Glycogen is synthesized from glucose
• Glycogen is degraded by phosphorolytic cleavage
• Glycogen metabolissm is regulated by hormones and metabolites
• Glycogen accumulates in several enzyme deficiencies
• Fructose is channeled into glycolysis/gluconeogenesis
• Excess fructose is problematic
• Excess galactose is channeled into the pathways of glucose metabolism
• The pentose phosphate pathway supplies NADPH and ribose-5-phosphate
• Fructose is the principal sugar in seminal fluid
• Amino sugars and sugar acids are made from glucose
• Summary
• Questions
• Chapter 25: The Metabolism of Fatty Acids and Triglycerides
• Fatty acids differ in chain length and number of double bonds
• Chylomicrons transport triglycerides from the intestine to other tissues
• Adipose tissue is specialized for the storage of triglycerides
• Fat metabolism in adipose tissue is under hormonal control
• Fatty acids are transported into the mitochondrion
• β-Oxidation produces acetyl-CoA, NADH, and FADH2
• Special fatty acids require special reactions
• The liver converts excess fatty acids to ketone bodies
• Fatty acids are synthesized from acetyl-CoA
• Acetyl-CoA is shuttled into the cytoplasm as citrate
• Fatty acid synthesis is regulated by hormones and metabolites
• AMP-Activated protein kinase adapts metabolic pathways to cellular energy status
• Most fatty acids can be synthesized from palmitate
• Fatty acids regulate gene expression
• Polyunsaturated fatty acids can be oxidized nonenzymatically
• Summary
• Questions
• Chapter 26: The Metabolism of Membrane Lipids
• Phosphatidic acid is an intermediate in phosphoglyceride synthesis
• Phosphoglycerides are remodeled continuously
• Sphingolipids are synthesized from ceramide
• Deficiencies of sphingolipid-degrading enzymes cause lipid storage diseases
• Cholesterol is the least soluble membrane lipid
• Cholesterol is derived from both endogenous synthesis and the diet
• Cholesterol biosynthesis is regulated at the level of HMG-CoA reductase
• Bile acids are synthesized from cholesterol
• Bile acids are subject to extensive enterohepatic circulation
• Most gallstones consist of cholesterol
• Summary
• Questions
• Chapter 27: Lipid Transport
• Most plasma lipids are components of lipoproteins
• Lipoproteins have characteristic lipid and protein compositions
• Dietary lipids are transported by chylomicrons
• VLDL is a precursor of LDL
• LDL is removed by receptor-mediated endocytosis
• Cholesterol regulates its own metabolism
• HDL is needed for reverse cholesterol transport
• Lipoproteins can initiate atherosclerosis
• Lipoproteins respond to diet and lifestyle
• Hyperlipoproteinemias are grouped into five phenotypes
• Hyperlipidemias are treated with diet and drugs
• Summary
• Questions
• Chapter 28: Amino Acid Metabolism
• Amino acids can be used for gluconeogenesis and ketogenesis
• The nitrogen balance indicates the net rate of protein synthesis
• The amino group of amino acids is released as ammonia
• Ammonia is detoxified to urea
• Urea is synthesized in the urea cycle
• Hyperammonemia can be treated with diet and drugs
• Some amino acids are closely related to common metabolic intermediates
• Glycine, serine, and threonine are glucogenic
• Proline, arginine, ornithine, and histidine are degraded to glutamate
• Methionine and cysteine are metabolically related
• Valine, leucine, and isoleucine are degraded by transamination and oxidative decarboxylation
• Phenylalanine and tyrosine are both glucogenic and ketogenic
• Melanin is synthesized from tyrosine
• Lysine and tryptophan have lengthy catabolic pathways
• The liver is the most important organ of amino acid metabolism
• Glutamine participates in renal acid-base regulation
• Summary
• Questions
• Chapter 29: Metabolism of Iron and Heme
• Iron is conserved very efficiently in the body
• Iron uptake by cells is regulated
• Dietary iron is absorbed in the duodenum
• Iron deficiency is the most common micronutrient deficiency worldwide
• Bone marrow and liver are the most important sites of heme synthesis
• Heme is synthesized from succinyl-CoA and glycine
• Porphyrias are caused by deficiencies of heme-synthesizing enzymes
• Heme is degraded to bilirubin
• Bilirubin is conjugated and excreted by the liver
• Elevations of serum bilirubin cause jaundice
• Many diseases can cause jaundice
• Summary
• Questions
• Chapter 30: The Metabolism of Purines and Pyrimidines
• Purine synthesis starts with ribose-5-phosphate
• Purines are degraded to uric acid
• Free purine bases can be salvaged
• Pyrimidines are synthesized from carbamoyl phosphate and aspartate
• DNA synthesis requires deoxyribonucleotides
• Many antineoplastic drugs inhibit nucleotide metabolism
• Uric acid has limited water solubility
• Hyperuricemia causes gout
• Abnormalities of purine-metabolizing enzymes can cause gout
• Gout can be treated with drugs
• Summary
• Questions
• Chapter 31: Micronutrients
• Riboflavin is a precursor of flavin mononucleotide and flavin adenine dinucleotide
• Niacin is a precursor of NAD and NADP
• Thiamine deficiency causes weakness and amnesia
• Vitamin B6 plays a key role in amino acid metabolism
• Pantothenic acid is a building block of coenzyme A
• Biotin is a coenzyme in carboxylation reactions
• Folic acid deficiency causes megaloblastic anemia
• Vitamin B12 requires intrinsic factor for its absorption
• Vitamin C is a water-soluble antioxidant
• Retinol, retinal, and retinoic acid are the active forms of vitamin A
• Vitamin D is a prohormone
• Vitamin E prevents lipid oxidation
• Many vitamins and phytochemicals are antioxidants
• Vitamin K is required for blood clotting
• Zinc is a constituent of many enzymes
• Copper participates in reactions of molecular oxygen
• Some trace elements serve very specific functions
• Summary
• Questions
• Chapter 32: Integration of Metabolism
• Insulin is released in response to elevated glucose
• Insulin stimulates the utilization of nutrients
• Protein synthesis is coordinated by the mTOR complex
• Glucagon maintains the blood glucose level
• Catecholamines mediate the flight-or-fight response
• Glucocorticoids are released in chronic stress
• Energy is expended continuously
• Stored fat and glycogen are degraded between meals
• Adipose tissue is the most important energy depot
• The liver converts dietary carbohydrates to glycogen and fat after a meal
• The liver maintains the blood glucose level during fasting
• Ketone bodies provide lipid-based energy during fasting
• Obesity is common in all affluent countries
• Appetite control is the most important determinant of obesity
• Obesity is related to insulin resistance
• Diabetes is caused by insulin deficiency or insulin resistance
• In diabetes, metabolism is regulated as in starvation
• Diabetes is diagnosed with laboratory tests
• Diabetes leads to late complications
• Many drugs are available for diabetes treatment
• Contracting muscle has three energy sources
• Physical exercise leads to adaptive changes
• Ethanol is metabolized to acetyl-CoA in the liver
• Liver metabolism is deranged by alcohol
• Alcohol abuse leads to fatty liver and liver cirrhosis
• Most “diseases of civilization” are caused by aberrant lifestyles
• Aging is the greatest challenge for medical research
• Antiaging treatments are being investigated
• Summary
• Questions
• Answers to Questions
• Chapter 1
• Chapter 2
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6
• Chapter 7
• Chapter 8
• Chapter 9
• Chapter 10
• Chapter 11
• Chapter 12
• Chapter 13
• Chapter 14
• Chapter 15
• Chapter 16
• Chapter 17
• Chapter 18
• Chapter 19
• Chapter 20
• Chapter 21
• Chapter 22
• Chapter 23
• Chapter 24
• Chapter 25
• Chapter 26
• Chapter 27
• Chapter 28
• Chapter 29
• Chapter 30
• Chapter 31
• Chapter 32
• Glossary
• Credits
• Index