What is the major function of the cytosol?
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Glycolysis, fatty acid synthesis.
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What is the major function of the cytosol?
Glycolysis, fatty acid synthesis.
What does determining the structure of a biomolecule allow?
Detailed correlations to be made between structure and function.
What type of reaction involves the transfer of electrons?
Oxidation-reduction (redox) reactions.
What is the functional group represented by -SH?
Sulfhydryl.
How many different centrifugation steps are used in the classic differential centrifugation method?
Three different centrifugation steps at successively greater speeds.
What organ was often used for pioneering work in subcellular fractionation?
Rat liver.
What is the basic unit of biology?
The cell.
What does gas-liquid chromatography (GLC) and thin-layer chromatography (TLC) allow the extensive study of?
Lipids.
What is the purpose of homogenization in subcellular fractionation?
To disrupt cells under mild conditions and extract organelles.
What are some of the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
Why is isolation of biomolecules in pure form important?
To determine the function of any biomolecule.
Which element plays a key role in numerous biologic processes?
Calcium.
Why is the rat hepatocyte extensively studied from a biochemical standpoint?
Due to its availability in relatively large amounts, suitability for fractionation studies, diversity of functions, and containing major organelles found in eukaryotic cells.
What did the introduction of the detergent SDS permit for electrophoresis?
The solubilization of many proteins that were previously insoluble.
What are the major constituents of most biomolecules?
Carbon, hydrogen, oxygen, and nitrogen.
What are the most frequent reactions encountered in biochemical processes?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is subcellular fractionation?
A biochemical method involving centrifugation to separate cellular components.
Why is it necessary to isolate organelles in relatively pure form?
To study their function in detail, free of significant contamination by other organelles.
What is the chemical formula for the aldehyde functional group?
-CHO
What determines the chemical properties of organic molecules?
Specific arrangement of atoms called functional groups.
What is the reciprocal relationship between biochemistry and medicine?
All diseases are manifestations of abnormalities of molecules, chemical reactions, or processes, hence a reciprocal relationship exists.
What is the role of AH2 in the oxidation-reduction reaction?
AH2 acts as a reducing agent.
What is the biochemical viewpoint of health?
A situation in which all intra- and extracellular reactions in the body are proceeding at rates in proportion with its maximal survival in the physiologic state.
What are the major causes of diseases related to immunologic reactions?
Anaphylaxis and autoimmune diseases.
What are the three major components of the experimental approach used in biochemistry?
What makes certain enzymes powerful tools in determining the structural features of biomolecules?
The known specificity of certain enzymes.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
Why was the whole animal considered too complex for definitive answers in biochemical research?
It was too complex to permit definitive answers to many questions.
What are the three physical techniques required for subcellular fractionation?
Extraction, Homogenization, Centrifugation.
What is the purpose of determining the structure of a biomolecule?
To allow detailed correlations to be made between structure and function.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What conditions are necessary for the extraction of organelles and biomolecules?
Mild conditions, such as the use of aqueous solutions, avoidance of extremes of pH and osmotic pressure, and avoidance of high temperatures.
What are the major methods used to separate and purify biomolecules?
Salt fractionation, chromatography, electrophoresis, ultracentrifugation, and others.
What does STKM stand for in the context of subcellular fractionation?
STKM stands for a solution consisting of 0.25 M sucrose, adjusted to pH 7.4 by 0.05 M TRIS (tris - [hydroxymethyl]aminomethane) HCl buffer, and K+ and Mg2+ at near physiologic concentrations.
Why do the thousands of reactions that occur in cells appear overwhelming at first look?
Due to the large number of reactions.
What is the significance of the Ester functional group?
It is polar and participates in H-bond formation.
What are polysaccharides made up of?
Simple carbohydrates (monosaccharides).
Where is the Ester functional group found?
In certain lipids.
How can cell fractions obtained through subcellular fractionation be assessed?
By measuring marker enzymes and chemicals, and by using the electron microscope.
What is the next step after purifying a biomolecule?
Determining its structure.
What is an example of an addition reaction in biochemical processes?
Hydration, such as the hydration of fumarate to form malate.
What are some of the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is the method used for fractionation of the contents of the homogenate?
Differential centrifugation.
How does WHO define health?
As a state of complete physical, mental, and social well-being and not merely the absence of disease and infirmity.
What is necessary to purify a biomolecule to homogeneity?
A combination of successive use of several methods.
What happens in an addition reaction?
Two molecules combine to form a single product.
What is the functional group of the organic biomolecule Alkene?
Alkenyl (-CH=CH-).
What is an example of an elimination reaction in biochemistry?
The dehydration of 2-phosphoglycerate to form phosphoenolpyruvate.
What are the building blocks of proteins?
Amino acids.
What is mostly found in the mitochondrial fraction?
Mitochondria, lysosomes, and peroxisomes.
Where are Ester functional groups found?
In certain lipids.
What is the significance of the Alkenyl functional group in biomolecules?
It is an important structural component, such as in lipids.
What is a metabolic pathway?
A series of reactions responsible for the synthesis of a more complex compound from one or more simple compounds (anabolic), or for the degradation of a compound to its end product (catabolic).
What are the most frequent reactions encountered in biochemical processes?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What developments helped usher in a period of unparalleled activity in biochemistry and cell histology after WWII?
Increasing availability of the electron microscope, introduction of methods for cell disruption under mild conditions, and increasing availability of the high-speed, refrigerated ultracentrifuge.
What was the initial approach for biochemical research on humans and animals?
Performed at the level of the whole animal.
Name some biologic agents that can cause diseases.
Viruses, bacteria, fungi, higher forms of parasites.
What happens to reducing agents when they donate electrons in redox reactions?
They become oxidized.
What is the normal chemical composition of carbohydrate in a 65-kg man?
1 kg, which is 1.5% of the body mass.
What is the family name of the functional group in Asparagine?
Amide (R-CONH2)
What are the major organelles found in a rat hepatocyte?
Nucleus, mitochondria, endoplasmic reticulum, free ribosomes, Golgi apparatus, lysosomes, peroxisomes, plasma membrane, and certain cytoskeletal elements.
What is the purpose of Table 1 - 5 in biochemistry?
To list the major methods used to analyze the structures of biomolecules.
What is the family name of the functional group -COOH?
Carboxylic acid (R-COOH).
What are the major complex biomolecules found in cells and tissues of higher animals?
Nucleic acids (DNA and RNA), proteins, carbohydrates (polysaccharides), and lipids.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What are the two types of metabolic processes?
Catabolism and Anabolism.
What does the isolated perfused organ method allow the study of?
An organ removed from the influence of other organs or the nervous system.
What is the significance of the ketone functional group?
It is polar and participates in H-bond formation.
What is the use of acid or alkaline hydrolysis in determining the structure of biomolecules?
To degrade the biomolecule under study into its basic constituents.
What is the family name for the aldehyde functional group?
Aldehyde (R-CHO)
What are the components of the STKM solution used for extraction of organelles?
0.25 M sucrose, 0.05 M TRIS HCl buffer, K+ and Mg2+ at near physiologic concentrations.
What does the sequential use of several techniques generally permit?
Purification of most biomolecules.
What aspects of chemistry does biochemistry combine?
All the fields of chemistry.
What do the contents of the final supernatant correspond to?
Those of the cytosol (cell sap).
What are electrophiles?
Atoms or groups that are transferred from one nucleophile to another.
What do biochemists study in relation to the speed of reactions?
How fast reactions occur.
Why is isolation of the cloned gene vital for studying the details of its structure and regulation?
It can reveal the amino acid sequence of the enzyme or protein for which it codes.
How can lack of oxygen lead to diseases?
Through loss of blood supply, depletion of the oxygen-carrying capacity of blood, and poisoning of oxidative enzymes.
What is the purpose of using tissue slices in biochemical research?
To remove the sliced tissue from other influences.
What is the advantage of using whole cells in biochemical research?
Particularly applicable to blood cells, which can be purified relatively easily.
What is the major function of the nucleus?
Site of chromosomes and transcription.
What is meant by purifying a biomolecule to homogeneity?
Freedom from contamination by any other biomolecule.
What was the initial level of biochemical research on humans and animals?
At the level of the whole animal.
What are the routine methods of choice for structural determination in biochemical methods?
Mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy.
What is the structure of the ketone functional group?
C - CO - C.
What preparations were developed to simplify biochemical research?
Simpler in vitro preparations.
In which biomolecules is the aldehyde functional group found?
Carbohydrates (aldoses)
What do the various preparations summarized in Table 1-6 allow to study?
Biochemical processes.
What are the major methods used to analyze the structures of biomolecules?
Elemental analysis, spectroscopy, acid/alkaline hydrolysis, enzyme degradation, mass spectrometry, specific sequencing methods, and X-ray crystallography.
What does each step of the classic differential centrifugation method yield?
A pellet and a supernatant.
What are the most frequent reactions encountered in biochemical processes?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
Name some elements encountered on an almost daily basis in medical practice in dealing with patients with electrolyte imbalances, iron-deficiency anemia, and thyroid diseases.
Potassium, sulfur, sodium, chlorine, magnesium, iron, manganese, and iodine.
What is the role of NADH in the oxidation-reduction reaction?
It acts as a reducing agent.
What is the structure of L-Cysteine?
H2N-C-COOH with CH2SH side chain.
Why was the whole animal considered too complex for definitive answers in biochemical research?
It presented many complications.
Where is the hydroxyl functional group found?
In carbohydrates.
What is the importance of biochemistry in genetics?
Biochemistry of nucleic acids is at the heart of genetics.
What are examples of chemical agents that can cause diseases?
Certain toxic compounds, therapeutic drugs, etc.
What occurs in redox reactions?
Transfer of electrons from a donor (reducing agent) to an electron acceptor (oxidizing agent).
Which type of reaction involves the removal of functional groups from a molecule?
Elimination reaction.
What happens to oxidizing agents when they accept electrons in redox reactions?
They become reduced.
What do biochemists concentrate on in living systems?
The chemical reactions that are occurring.
What is the major function of the plasma membrane?
Transport of molecules in and out of cells; intercellular adhesion and communication.
What did the use of electron microscope reveal in cellular components?
Many previously unknown or poorly observable components.
What is the use of measurement of blood T4 or TSH in the neonatal diagnosis of congenital hypothyroidism?
To act as screening tests for the early diagnosis of congenital hypothyroidism.
Why was it realized that the whole animal was too complex for definitive answers in biochemical research?
Because it presented many complications.
What are the chief components of the human body?
Protein, fat, carbohydrate, water, and minerals.
What type of reaction forms a double bond by removing atoms from a molecule?
Elimination reaction.
What is the family name for the ketone functional group?
Ketone (R - CO - R’).
What happens when hydrogen atoms on organic molecules are replaced by different functional groups?
Different families of organic compounds result.
What are the major organic biomolecules of the human body?
Nucleic acids, proteins, lipids, and carbohydrates.
What is the family name of the Ester functional group?
Ester (R - COOR’)
At what temperature are most procedures for isolating organelles performed?
About 0 to 4 °C.
How many pellets are yielded in the classic differential centrifugation method?
Three pellets.
Are lipids polymers of fatty acids?
No, lipids are not polymers of fatty acids.
What are the two types of metabolic processes?
Catabolism and anabolism.
What is the purpose of specific sequencing methods in determining the structures of biomolecules?
To determine the sequence of proteins and nucleic acids.
What are the two configurations of the Alkenyl functional group?
cis and trans configuration.
Which element has the highest percentage in the human body on a dry weight basis?
Carbon.
Where are complex biomolecules generally found?
In lower organisms.
What is the relationship between immunology and biochemistry?
Immunology uses numerous biochemical techniques.
Why is a sound knowledge of biochemistry and physiology important in pharmacology and pharmacy?
Pharmacology and pharmacy require a sound knowledge of biochemistry and physiology.
How is biochemistry similar to molecular biology?
Both fields study living systems at the molecular level.
What is the definition of biochemistry?
The study of chemical processes within and relating to living organisms.
What is the major function of the peroxisome?
Degradation of certain fatty acids and amino acids; production and degradation of hydrogen peroxide.
What is the functional group of Asparagine?
Amido (-CONH2)
What method permitted the isolation and analysis of cellular components in vitro?
Disruption and ultracentrifugation.
What are the major constituents of the three fractions obtained through subcellular fractionation?
Nuclei, mitochondria, and microsomes.
What is the functional group represented by H2N-C-COOH?
Amino group (-NH2).
What forces are exerted on cells during homogenization?
Mechanical shearing forces.
What preparations were developed to simplify biochemical research?
Simpler in vitro preparations.
What is the resulting solution called after homogenization?
Homogenate, which contains many intact organelles.
What are the primary functions of metabolism?
Acquisition and utilization of energy, synthesis of molecules needed for cell structure and functioning, and removal of waste products.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is catabolism?
A set of metabolic pathways that breaks down molecules into smaller units, which are either oxidized to release energy, or used in other reactions.
What is the family name of the functional group Alkenyl?
Alkene (R-CH=CH-R').
What was the initial level of biochemical research on humans and animals?
The level of the whole animal.
How are biochemical investigations used to demonstrate the nature of genetic defects in cystic fibrosis?
By revealing the nature of the genetic defects.
How are organic solvents used in subcellular fractionation?
Organic solvents are used for the extraction of lipids and nucleic acids.
How are biochemical investigations used to suggest rational treatment of diseases?
By recommending specific treatments based on biochemical findings.
Why does organic chemistry play a large part in biochemistry?
Because carbon is the element of life.
What is the role of isolation and characterization of metabolites and enzymes in biochemical analysis?
It is a vital part in the analysis of any chemical reaction or pathway.
What do all life processes consist of?
Chemical reactions catalyzed by enzymes.
What are chemical reactions in a living system collectively known as?
Metabolism.
What are genetic disorders in the context of biochemistry?
They can be congenital or molecular.
What type of reaction involves the transfer of electrons between chemical species?
Oxidation-reduction (redox) reaction.
How are isolated cell organelles used in biochemical research?
Extensively used to study the function of mitochondrion, the endoplasmic reticulum, ribosomes, etc.
What is subcellular fractionation and why is it important?
It is the process of isolating and studying the components of a cell, important for understanding cellular functions.
What is the significance of the functional group in Asparagine?
Polar, but does not bear a charge. Participates in H-bond formation.
What is the functional group in the given biomolecule?
Carboxyl (-COOH).
How is the progress of infectious hepatitis monitored?
By using the plasma enzyme alanine aminotransferase (ALT).
What are the most frequent reactions encountered in biochemical processes?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is the focus of Biochemistry?
The chemistry of living organisms and the chemical constituents of living cells.
What is the significance of the carboxyl functional group?
It is polar and participates in H-bond formation. It is weakly acidic and bears a negative charge when it donates a proton.
What are the building blocks of nucleic acids?
Nucleotides.
What is one of the most common biochemical isomerization reactions?
The interconversion between aldose and ketose sugars.
What is the role of O2 in the oxidation-reduction reaction?
O2 acts as an oxidizing agent.
What are the major prerequisites for the maintenance of health?
Optimal dietary intake of vitamins, nutritionally essential amino acids, nutritionally essential fatty acids, various minerals, water, and carbohydrates.
What are the three pellets obtained from the overall procedure of classic differential centrifugation?
Nuclear, mitochondrial, and microsomal fractions.
What is anabolism?
A set of metabolic pathways that construct or build molecules from smaller units.
What are the names of the three pellets obtained in the classic differential centrifugation method?
Nuclear, mitochondrial, and microsomal fractions.
What are biopolymers composed of?
Repeating units of their building blocks.
What is the normal chemical composition of water in a 65-kg man?
40 kg, which is 61.6% of the body mass.
What is an example of a biomolecule containing the hydroxyl functional group?
D-Glucose.
What happens in a nucleophilic substitution reaction?
The attacking species (nucleophile) is attracted to an electrophile, forming a new bond and breaking the old one.
What is an example of an element incorporated into biochemical structures?
Iron in hemoglobin.
What type of chemistry involves determining amounts and structures using sophisticated instrumentation?
Analytical chemistry.
What is a metabolic pathway?
A series of chemical reactions occurring within a cell.
What is the purpose of using homogenate in biochemical research?
To ensure a cell-free preparation and study the effects of specific compounds.
What are the major elements of the human body?
Oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.
What is necessary to purify a biomolecule to homogeneity?
A combination of successive use of several methods.
What did the introduction of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) make possible?
Analysis of membrane and many other proteins.
What was the initial level of biochemical research on humans and animals?
At the level of the whole animal.
What does Biochemistry encompass?
Large areas of cell biology, molecular biology, and molecular genetics.
What is the structure of the Ester functional group?
R―C―O―R’
What do isomerization reactions involve?
The intramolecular shift of atoms or groups.
Which method provides the most detailed information about the structure of biomolecules?
X-ray diffraction and crystallography.
What is subcellular fractionation?
The process of isolating organelles from cells using centrifugation and different homogenization media.
What does the nuclear fraction mostly contain?
Nuclei, plasma membrane, and unruptured cells.
What is the role of NAD+ in the oxidation-reduction reaction?
It acts as an oxidizing agent.
What is the significance of the sulfhydryl group in biomolecules?
It does not participate in H-bond formation and is less soluble in water than alcohols.
What is the product of an oxidation-reduction reaction involving pyruvate and NADH?
Lactate, NAD+ and a reducing agent.
What is the significance of the hydroxyl functional group?
It is polar and participates in H-bond formation.
What are the major causes of diseases in biochemistry?
Physical agents, chemical agents, biologic agents, lack of oxygen, and genetic disorders.
What is the approximate percentage of carbon in the human body on a dry weight basis?
50%.
Give examples of physical agents that can cause diseases.
Mechanical trauma, extreme temperature, sudden changes in atmospheric pressure, radiation, electric shock.
What is an example of rational treatment of diseases using biochemical investigations?
Use of a diet low in phenylalanine for the treatment of phenylketonuria (PKU).
What is the approximate percentage of oxygen in the human body on a dry weight basis?
20%.
What is the significance of the increasing availability of the electron microscope?
It contributed to a period of unparalleled activity in biochemistry and cell histology.
What is the significance of the increasing availability of the high-speed, refrigerated ultracentrifuge?
It is capable of generating centrifugal forces sufficient to separate the components of disrupted cells from one another without overheating them.
What type of reaction involves the rearrangement of atoms within a molecule?
Isomerization reaction.
What is subcellular fractionation?
A biochemical method involving centrifugation to isolate organelles in more or less pure form.
What is the purpose of subfractionation of organelles in biochemical research?
Extensively used in studies of mitochondrial function.
What is the major function of the ribosome?
Protein synthesis.
Why is the isolation of biomolecules in pure form important?
To determine the function of the biomolecule.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is the aim of Biochemistry?
To describe and explain, in molecular terms, all chemical processes of living cells.
What are the most frequent biochemical reactions?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
How are the structures of many proteins and complex carbohydrate chains determined?
By high-resolution NMR spectroscopy.
Which element is a component of nucleic acids and other molecules, and is widely distributed in its ionized form in the human body?
Phosphorous.
What is the structure of the Ester functional group?
R―C―O―R’
What is the functional group of hydroxyl?
-OH
What is the significance of the aldehyde functional group?
It is polar and participates in H-bond formation.
What allows water to function as a solvent in the human body?
Its polar nature and ability to form hydrogen bonds.
Which organs are particularly suitable for the isolated perfused organ method?
Liver, heart, and kidney.
What are the major causes of diseases related to nutritional imbalances?
Deficiencies and excesses.
What can cause significant losses of activity during extraction at room temperature?
The action of various enzymes that are released when cells are disrupted.
What is the role of NADH in the oxidation-reduction reaction?
It acts as a reducing agent.
What are nucleophiles most commonly?
Negatively-charged atoms or groups.
What is the role of NAD+ in the oxidation-reduction reaction?
It acts as an oxidizing agent.
What are the most frequent reactions encountered in biochemical processes?
Nucleophilic substitution, elimination, addition, isomerization, oxidation-reduction (redox), and hydrolysis reactions.
What is the approximate percentage of hydrogen in the human body on a dry weight basis?
10%.
Which element has the highest percentage after carbon, oxygen, and hydrogen in the human body on a dry weight basis?
Nitrogen.
In what areas of pathology are biochemical approaches being used?
Biochemical approaches are being used increasingly to study the basic aspects of pathology, such as inflammation, cell injury, and cancer.
What are the products of the hydrolysis of ATP?
Adenosine diphosphate (ADP) and inorganic phosphate (Pi).
What is the major function of the mitochondrion?
Citric acid cycle and oxidative phosphorylation.
What is the major function of the endoplasmic reticulum?
Protein synthesis (RER); synthesis of various lipids (SER), oxidation of many xenobiotics (SER).
How are organs and their cells disrupted during the process of homogenization?
By rotating a manually operated or motor-driven pestle within a glass tube containing minced fragments of the organs and a homogenizing medium.
What is a marker enzyme or chemical in the context of subcellular fractionation?
An enzyme or chemical almost exclusively confined to one particular organelle, indicating the presence or absence of that organelle in a fraction.
Why is it necessary to extract a specific organelle or molecule from cells?
To isolate and study it.
What is the family name for the functional group R-NH2?
Amine (R-NH2).
What is the family name of the Ester functional group?
Ester (R - COOR’)
What is the family name for the functional group R-SH?
Thiol.
What is the method used for fractionation of the contents of the homogenate?
Differential centrifugation.
What is the family name for the functional group R-OH?
Alcohol
How are biomolecules precipitated in salt fractionation?
By precipitation with ammonium sulfate.
What is the next abundant component after water in the human body?
Protein.
What allows simplifying the overall picture of metabolism?
The relatively small number of reaction types, simple mechanisms used in biochemical reactions, and the relatively few number of reactions of central importance.
What is the order of abundance of components in the human body after water?
Protein, fat, minerals, and carbohydrates.
Which biomolecules are considered biopolymers?
Nucleic acids, proteins, and polysaccharides.
How does physiology relate to biochemistry?
Physiology overlaps with biochemistry almost completely.
What is the normal chemical composition of fat in a 65-kg man?
9 kg, which is 13.8% of the body mass.
What is the normal chemical composition of minerals in a 65-kg man?
4 kg, which is 6.1% of the body mass.
How do poisons relate to biochemistry?
Poisons act on biochemical reactions or processes.
How are biochemical approaches used in microbiology?
Many workers in microbiology employ biochemical approaches almost exclusively.
How does biochemistry contribute to health sciences?
By providing insights into the molecular mechanisms of diseases and the development of new treatments.
What is the major function of the Golgi apparatus?
Intracellular sorting of proteins; glycosylation reactions; sulfation reactions.
What is the process of nucleophilic substitution reaction?
A nucleophile (A:) replaces a leaving group (X:) in a molecule (B‒X) to form a new compound (A‒B).
What is the purpose of measuring blood carcinoembryonic antigen (CEA) in certain patients who have been treated for colon cancer?
To assist in assessing the responses of diseases to therapy.
What is the major component of the human body?
Water.
What does Biochemistry attempt to understand?
How life began.
What is hydrolysis?
The cleavage of a covalent bond by water.
Name the frequently encountered and important functional groups in organic biomolecules.
Hydroxyl, Aldehyde, Ketone, Carboxyl, Ester, Amino, Amido, Sulfhydryl, Alkenyl.
What type of diseases are sickle-cell anemia, atherosclerosis, and diabetes mellitus?
Genetic diseases.
Where is the ketone functional group found in biomolecules?
In carbohydrates (ketoses) like D-Fructose.
What is the applicability of the described procedure for subcellular fractionation?
It is applicable in general to most organs and cells.
How is the digestion of proteins in the stomach catalyzed?
In acid-catalyzed reactions.
What is the speed and duration of the third centrifugation step in the classic differential centrifugation method?
105,000 g for 60 minutes.
What preparations were developed to remove complications experienced at the level of the whole animal?
Simpler in vitro preparations.
What is the normal chemical composition of protein in a 65-kg man?
11 kg, which is 17.0% of the body mass.
What type of reaction involves the substitution of a nucleophile for a leaving group?
Nucleophilic substitution reaction.
What constitutes metabolism?
The combined catabolic and anabolic processes.
How are liver slices used in biochemical research?
Liver slices have been especially used; however, they tend to deteriorate within a few hours.
What is the major function of the lysosome?
Site of many hydrolases.
What is the significance of the amino functional group?
It is polar and participates in H-bond formation. It is weakly basic and bears a positive charge when it accepts a proton.
What is the significance of the Ester functional group?
It is polar and participates in H-bond formation.
What is the role of biochemical investigations in relation to diseases?
To reveal the fundamental causes and mechanisms of diseases.
What type of reactions are usually involved in hydrolysis?
Nucleophilic substitution either at a saturated carbon or a carbonyl carbon.
What is a nucleophile?
A species that is attracted to an electrophile and substitutes one atom or group for another.
What are the major causes of diseases related to hormonal imbalances?
Hormonal deficiencies and excesses.
What is the principal monosaccharide found in human tissues that makes up glycogen?
Glucose.
How do the major causes of diseases influence the body?
By influencing various biochemical mechanisms in the cell or in the body.
What is another name for oxidation-reduction reaction?
Redox reaction.
How do biochemical investigations assist in the diagnosis of specific diseases?
By using specific biomarkers or enzymes for diagnosis.
Do lower organisms have the same building blocks for complex biomolecules as higher organisms?
In certain cases, the building blocks may differ.
What are some examples of building blocks found in lower organisms?
Other polysaccharides and lipids.
What are the two simple rules to determine whether a molecule has been oxidized or reduced?
Oxidation occurs if a molecule gains oxygen or loses hydrogen. Reduction occurs if a molecule loses oxygen or gains hydrogen.
What are the aims of biochemistry?
To understand the structure and function of biomolecules, and their role in the processes of life.
What are the important functional groups in biomolecules?
Hydroxyl, carbonyl, carboxyl, amino, and phosphate groups.
How have modifications of centrifugation allowed the isolation of organelles?
By using different homogenization media or protocols.
What happens in an elimination reaction involving biomolecules with a hydroxyl functional group?
The removal of H2O.
How is mass spectrometry used in determining the structures of biomolecules?
It is used to analyze the mass and composition of biomolecules.
What does the microsomal fraction (microsomes) mostly contain?
A mixture of SER, RER, and free ribosomes.
Who established the cell as the fundamental unit of biologic activity in the 19th century?
Schleiden, Schwann, and other pioneers such as Virchow.
Define catabolism.
A set of metabolic pathways that breaks down molecules into smaller units, which are either oxidized to release energy, or used in other reactions.
What is the content of the supernatant from each step in the classic differential centrifugation method subjected to?
Centrifugation in the next step.
What is the significance of the introduction of methods that permit disruption of cells under relatively mild conditions?
It preserved cell function and contributed to the period of unparalleled activity in biochemistry and cell histology.
Why was the whole animal considered too complex for definitive answers in biochemical research?
It was too complex to permit definitive answers to many questions.
What preparations were developed to remove complications experienced at the level of the whole animal?
Simpler in vitro preparations.
What is the approximate percentage of nitrogen in the human body on a dry weight basis?
8.5%.
What type of reaction involves the breaking of a chemical bond through the addition of water?
Hydrolysis reaction.
What is the major function of the cytoskeleton?
Microfilament, microtubules, intermediate filaments.
What important cellular process is driven by breaking the phosphate bonds of ATP?
Many cellular processes.
Define anabolism.
A set of metabolic pathways that construct or build molecules from smaller units.
What is an example of using an enzyme for the diagnosis of myocardial infarction?
Use of the enzyme creatine kinase MB (CK-MB) in the diagnosis of myocardial infarction (heart attack).
What type of reaction involves the addition of atoms or groups to a molecule?
Addition reaction.
Which components make up the chief components of the human body?
Protein, fat, carbohydrate, water, and minerals.
How are modifications of the basic approach of subcellular fractionation achieved?
By using different homogenization media or different protocols or methods of centrifugation.
What are the common chemical reactions in living organisms?
Metabolism, photosynthesis, and cellular respiration.
What are the two elements with the highest percentage after carbon, oxygen, hydrogen, and nitrogen in the human body on a dry weight basis?
Calcium and phosphorous.
What developments led to significant progress in biochemistry?
Advances in technology, such as DNA sequencing and structural biology techniques.
What are the major components of the experimental approach in biochemistry?
Isolation, purification, and characterization of biomolecules and enzymes.
Name the major organic biomolecules of the human body.
Carbohydrates, lipids, proteins, and nucleic acids.
