Chemical building blocks of matter
Matter. Anything that has mass and occupies space. Ex. atom, air, water, rocks, bacteria Atom. Smallest chemical unit of matter Atoms are building blocks for more complex substances. i.e. atoms interact with each other to produce various chemical substances such as the oxygen we breath, water, salt, proteins, etc. Element. Substance composed of same kind of atoms Major elements present in living organisms C = Carbon H = Hydrogen N = Nitrogen O = Oxygen P = Phosphorus Molecule. Chemical combination of 2 or more atoms Ex. O2, molecular oxygen (Fig. 2.3) Compound. Molecule made of 2 or more elements Ex. carbon dioxide, CO2
Matter. Anything that has mass and occupies space. Ex. atom, air, water, rocks, bacteria
Atom. Smallest chemical unit of matter
Atoms are building blocks for more complex substances. i.e. atoms interact with each other to produce various chemical substances such as the oxygen we breath, water, salt, proteins, etc.
Element. Substance composed of same kind of atoms
Major elements present in living organisms C = Carbon H = Hydrogen N = Nitrogen O = Oxygen P = Phosphorus
Major elements present in living organisms
C = Carbon H = Hydrogen N = Nitrogen O = Oxygen P = Phosphorus
Molecule. Chemical combination of 2 or more atoms
Ex. O2, molecular oxygen (Fig. 2.3)
Compound. Molecule made of 2 or more elements
Ex. carbon dioxide, CO2
What are N2 and H2O ?
The structure of atoms (See Fig. 2.1)
Electron shell. Region around the nucleus where electrons orbit (See Fig. 2.2) Inner most shell holds only 2 electrons The atoms of most elements of living organisms are stable when 8 electrons are in the outer shell (Hydrogen only has one shell, so it is stable when 2 electrons are present) An atom has a neutral charge because it has the same number positive (protons) and negative (electrons) charges Ion. An atom that carries a charge because it has gained or lost electrons in order to acquire a stable outer shell. The number of protons and electrons are no longer equal (Fig. 2.6) Ex. Na+ Sodium ion resulting from the loss of one electron from the outer shell of a neutral Sodium atom Cl- Chlorine ion resulting from the gain of one electron the outer shell of a neutral Chlorine atom Ca++ Calcium ion resulting from the loss of 2 electrons from the outer shell of a neutral Calcium atom
Electron shell. Region around the nucleus where electrons orbit (See Fig. 2.2)
Inner most shell holds only 2 electrons The atoms of most elements of living organisms are stable when 8 electrons are in the outer shell (Hydrogen only has one shell, so it is stable when 2 electrons are present) An atom has a neutral charge because it has the same number positive (protons) and negative (electrons) charges
Inner most shell holds only 2 electrons
The atoms of most elements of living organisms are stable when 8 electrons are in the outer shell
(Hydrogen only has one shell, so it is stable when 2 electrons are present)
An atom has a neutral charge because it has the same number positive (protons) and negative (electrons) charges
Ion. An atom that carries a charge because it has gained or lost electrons in order to acquire a stable outer shell.
The number of protons and electrons are no longer equal (Fig. 2.6) Ex. Na+ Sodium ion resulting from the loss of one electron from the outer shell of a neutral Sodium atom Cl- Chlorine ion resulting from the gain of one electron the outer shell of a neutral Chlorine atom Ca++ Calcium ion resulting from the loss of 2 electrons from the outer shell of a neutral Calcium atom
The number of protons and electrons are no longer equal (Fig. 2.6)
Ex.
Na+ Sodium ion resulting from the loss of one electron from the outer shell of a neutral Sodium atom
Cl- Chlorine ion resulting from the gain of one electron the outer shell of a neutral Chlorine atom
Ca++ Calcium ion resulting from the loss of 2 electrons from the outer shell of a neutral Calcium atom
Cation. A positively charged ion Anion. A negatively charged ion
Cation. A positively charged ion
Anion. A negatively charged ion
3 Types 1) Ionic bond. Attraction between a cation and an anion (opposite charges attract) Ex. Na+Cl- (table salt) 2) Covalent bond. Sharing of electrons between atoms (represented as a solid line) Allows both atoms to have completely filled outer electron shells
3 Types
1) Ionic bond. Attraction between a cation and an anion (opposite charges attract) Ex. Na+Cl- (table salt) 2) Covalent bond. Sharing of electrons between atoms (represented as a solid line) Allows both atoms to have completely filled outer electron shells
1) Ionic bond. Attraction between a cation and an anion (opposite charges attract)
Ex. Na+Cl- (table salt)
2) Covalent bond. Sharing of electrons between atoms (represented as a solid line)
Allows both atoms to have completely filled outer electron shells
3) Hydrogen bond. Attraction between partially postive (d+) hydrogen atom of one molecule and a partially negative (d-) atom of another molecule (d, "delta" is the symbol used to designate a partial rather than a *full positive or negative charge) *Note that cations and anions have full positive or negative charges Partial charges exist when there is unequal sharing of electrons in a covalent bond between two atoms of a molecule. Ex. H2O (Fig. 2.5)
3) Hydrogen bond. Attraction between partially postive (d+) hydrogen atom of one molecule and a partially negative (d-) atom of another molecule
(d, "delta" is the symbol used to designate a partial rather than a *full positive or negative charge) *Note that cations and anions have full positive or negative charges Partial charges exist when there is unequal sharing of electrons in a covalent bond between two atoms of a molecule. Ex. H2O (Fig. 2.5)
(d, "delta" is the symbol used to designate a partial rather than a *full positive or negative charge)
*Note that cations and anions have full positive or negative charges
Partial charges exist when there is unequal sharing of electrons in a covalent bond between two atoms of a molecule.
Ex. H2O (Fig. 2.5)
See Fig. 2.8 Note: The hydrogen bond is between an oxygen atom of one water molecule and a hydrogen atom of another water molecular (represented as a dashed line). The bond between O and H of the same water molecule is a covalent bond. Comparison of Bond Strengths Strongest ---------------------------> Weakest Covalent.......>........Ionic........>...... Hydrogen
See Fig. 2.8
Note: The hydrogen bond is between an oxygen atom of one water molecule and a hydrogen atom of another water molecular (represented as a dashed line). The bond between O and H of the same water molecule is a covalent bond.
Comparison of Bond Strengths
Strongest ---------------------------> Weakest
Covalent.......>........Ionic........>...... Hydrogen
Chemical reactions. Formation or breakage of bonds between atoms
Energy is stored in a chemical bond Bond formation requires input of energy Chemical reaction X + Y + energy -----------------------> X-Y
Energy is stored in a chemical bond
Bond formation requires input of energy
Chemical reaction
X + Y + energy -----------------------> X-Y
Bond breakage releases energy stored in the bond Chemical reaction X-Y -----------------------------> X + Y + energy
Bond breakage releases energy stored in the bond
X-Y -----------------------------> X + Y + energy
Metabolism. The chemical reactions that occur inside cells of living organisms.
Two types: Anabolism. Reactions that require energy to form covalent bonds Involved in biosynthesis of cellular components Ex. Proteins, cell walls, DNA, lipids
Two types:
Anabolism. Reactions that require energy to form covalent bonds
Involved in biosynthesis of cellular components Ex. Proteins, cell walls, DNA, lipids
Involved in biosynthesis of cellular components
Ex. Proteins, cell walls, DNA, lipids
Catabolism. Reactions that break bonds, releasing the energy stored in the bonds Supplies the energy needed for anabolic reactions Ex. Breakdown of high energy food molecules such as carbohydrates (sugars) and lipids (fats)
Catabolism. Reactions that break bonds, releasing the energy stored in the bonds
Supplies the energy needed for anabolic reactions Ex. Breakdown of high energy food molecules such as carbohydrates (sugars) and lipids (fats)
Supplies the energy needed for anabolic reactions
Ex. Breakdown of high energy food molecules such as carbohydrates (sugars) and lipids (fats)
D. Water and solutions
Living organisms are mostly water
Has important properties necessary for life
1. A polar solvent Dissolves ionic and polar compounds to form solutions (Fig. 2.7) Ex. Salt and sugar solutions Does not form solutions with nonpolar compounds like oils and fats Ex. Oil doesn't dissolve in water and floats on the surface when the two are combined
1. A polar solvent
Dissolves ionic and polar compounds to form solutions (Fig. 2.7) Ex. Salt and sugar solutions Does not form solutions with nonpolar compounds like oils and fats Ex. Oil doesn't dissolve in water and floats on the surface when the two are combined
Dissolves ionic and polar compounds to form solutions (Fig. 2.7)
Ex. Salt and sugar solutions
Does not form solutions with nonpolar compounds like oils and fats
Ex. Oil doesn't dissolve in water and floats on the surface when the two are combined
2. Medium for metabolic reactions between dissolved compounds in the cytoplasm of a cell 3. Participates as a reactant or product in many metabolic reactions Hydrolysis rxn. Ex. H2O + X-Y -------------------------> X-H + Y-OH 4. Stores or releases heat with little temperature change Most organisms need a stable temperature to function properly 5. Weakly ionic --some molecules dissociate into H+ and OH- (hydroxyl) ions
2. Medium for metabolic reactions between dissolved compounds in the cytoplasm of a cell
3. Participates as a reactant or product in many metabolic reactions
Hydrolysis rxn. Ex. H2O + X-Y -------------------------> X-H + Y-OH
Hydrolysis rxn.
Ex. H2O + X-Y -------------------------> X-H + Y-OH
4. Stores or releases heat with little temperature change
Most organisms need a stable temperature to function properly
5. Weakly ionic --some molecules dissociate into H+ and OH- (hydroxyl) ions
pH, acids and bases
pH A measure of the concentration of H+ of water (Table 2.2)
Pure water is neutral, i.e. the concentrations of H+ and OH- ions are the same [H+] = [OH-] = 0.0000001 moles/liter (10-7 moles/liter) The pH value of a water solution is the negative logarithm of [H+] -log 10-7 = 7.0; so the pH value of pure water is 7.0
Pure water is neutral, i.e. the concentrations of H+ and OH- ions are the same
[H+] = [OH-] = 0.0000001 moles/liter (10-7 moles/liter)
The pH value of a water solution is the negative logarithm of [H+]
-log 10-7 = 7.0; so the pH value of pure water is 7.0
The pH scale
7.0 is the middle of the pH scale (range 0-14, see Fig. 2.13) Pure water and aqueous solutions have a pH value of 7.0 (called neutral) A solution with a pH value below 7.0 is acidic (it has a higher concentration of hydrogen ions than pure water) A solution with a value above 7.0 is basic (it has a lower concentration of hydrogen ions than pure water) Each whole unit of pH represents a 10-fold increase or decrease in [H+]
7.0 is the middle of the pH scale (range 0-14, see Fig. 2.13)
Pure water and aqueous solutions have a pH value of 7.0 (called neutral) A solution with a pH value below 7.0 is acidic (it has a higher concentration of hydrogen ions than pure water) A solution with a value above 7.0 is basic (it has a lower concentration of hydrogen ions than pure water) Each whole unit of pH represents a 10-fold increase or decrease in [H+]
Pure water and aqueous solutions have a pH value of 7.0 (called neutral)
A solution with a pH value below 7.0 is acidic (it has a higher concentration of hydrogen ions than pure water)
A solution with a value above 7.0 is basic (it has a lower concentration of hydrogen ions than pure water)
Each whole unit of pH represents a 10-fold increase or decrease in [H+]
Acid. Chemical compound that releases a hydrogen ion (H+)when added to water
Ex. Acetic acid CH3COOH ----------> H+ + CH3COO- This increases the concentration of hydrogen ions in the solution, decreasing the pH
Ex. Acetic acid
CH3COOH ----------> H+ + CH3COO-
This increases the concentration of hydrogen ions in the solution, decreasing the pH
Base. Chemical compound that accepts H+ or releases a hydroxyl ion (OH-) in water
Ex. 1. Ammonia NH3 + H+ ---------> NH4+ Ex. 2. Sodium hydroxide NaOH ---------> Na+ + OH- OH- + H+ --------> H2O OH- and H+ combine to form H2O which decreases [H+] So, both types of bases decrease the concentration of hydrogen ions in the solution, increaseing the pH Exs. 1. You add acetic acid to pure water which increases the [H+] If: pH = 6, the [H+] is 10 X greater than that of pure water pH = 5, the [H+] is 100 X greater than that of pure water
Ex. 1. Ammonia
NH3 + H+ ---------> NH4+
Ex. 2. Sodium hydroxide
NaOH ---------> Na+ + OH- OH- + H+ --------> H2O OH- and H+ combine to form H2O which decreases [H+]
NaOH ---------> Na+ + OH-
OH- + H+ --------> H2O
OH- and H+ combine to form H2O which decreases [H+]
So, both types of bases decrease the concentration of hydrogen ions in the solution, increaseing the pH
Exs.
1. You add acetic acid to pure water which increases the [H+]
If: pH = 6, the [H+] is 10 X greater than that of pure water pH = 5, the [H+] is 100 X greater than that of pure water
If: pH = 6, the [H+] is 10 X greater than that of pure water
pH = 5, the [H+] is 100 X greater than that of pure water
2. You add ammonia to pure water which decreases the [H+] If: pH = 8, the [H+] is 10 X smaller than that of pure water pH = 10, the [H+] is __?__ smaller than that of pure water
2. You add ammonia to pure water which decreases the [H+]
If: pH = 8, the [H+] is 10 X smaller than that of pure water pH = 10, the [H+] is __?__ smaller than that of pure water
If: pH = 8, the [H+] is 10 X smaller than that of pure water
pH = 10, the [H+] is __?__ smaller than that of pure water
Remember: 1) Solutions with pH values below 7.0 are acidic and those with pH values above 7.0 are basic 2) A solution with a low pH has a higher [H+] than a solution with a higher pH
Remember:
1) Solutions with pH values below 7.0 are acidic and those with pH values above 7.0 are basic 2) A solution with a low pH has a higher [H+] than a solution with a higher pH
1) Solutions with pH values below 7.0 are acidic and those with pH values above 7.0 are basic
2) A solution with a low pH has a higher [H+] than a solution with a higher pH
Most microorganisms prefer pH near 7.0. The pH of the cytoplasm and of their environment affects their growth and survival.
Acidophiles and alkalophiles are unusual microorganisms that thrive in acidic or basic environments
The Chemical Makeup of Microbial Cells
Organic compounds. Contain C and H (may also contain other elements such as oxygen, nitrogen and phosphorus)
Ex. CH4 (methane) CH3-COOH (acetic acid) C6H12O6 (glucose) Why aren't NaOH, NaCl, H2O, CCl4 and NH3 organic compounds?
Ex. CH4 (methane)
CH3-COOH (acetic acid)
C6H12O6 (glucose)
Why aren't NaOH, NaCl, H2O, CCl4 and NH3 organic compounds?
Reduced organic compounds contain more H and little or no O
Have a high energy content, supports good growth of microorganisms Ex. CH4
Have a high energy content, supports good growth of microorganisms
Ex. CH4
Oxidized organic compounds contain less H and more oxygen
Have a lower energy content E.x. HCO2H (formic acid) Can't support as much growth as CH4 CO2 (carbon dioxide) The most oxidized form of carbon in cells Not organic by deffinition, but is the waste product produced by catabolism of organic compounds used to support the growth of microorganisms Has no usable energy to support growth
Have a lower energy content
E.x.
HCO2H (formic acid)
Can't support as much growth as CH4
CO2 (carbon dioxide)
The most oxidized form of carbon in cells Not organic by deffinition, but is the waste product produced by catabolism of organic compounds used to support the growth of microorganisms Has no usable energy to support growth
The most oxidized form of carbon in cells
Not organic by deffinition, but is the waste product produced by catabolism of organic compounds used to support the growth of microorganisms
Has no usable energy to support growth
Functional groups affect the properties of organic compounds (Table 2.3)
Complex organic compounds
Contain more atoms and functional groups than simple organic compounds
Many are polymers of simple organic compounds
Ex. Starch and cellulose are polymers of glucose (Fig. 2.17) Proteins are polymers of amino acids DNA (deocyribonucleic acid) and RNA (ribonucleic acid) are polymers of nucleotides
Starch and cellulose are polymers of glucose (Fig. 2.17)
Proteins are polymers of amino acids
DNA (deocyribonucleic acid) and RNA (ribonucleic acid) are polymers of nucleotides
Cellular functions
-Components of cell structures Ex. Cell walls, membranes, cell capsules, flagella -Catalysts that speed up metabolic reactions Ex. Enzymes -Storage and retrieval of information necessary for life DNA -----> RNA -----> Proteins -Storage of energy Ex. starch, a polymer of glucose
-Components of cell structures
Ex. Cell walls, membranes, cell capsules, flagella
-Catalysts that speed up metabolic reactions
Ex. Enzymes
-Storage and retrieval of information necessary for life
DNA -----> RNA -----> Proteins
-Storage of energy
Ex. starch, a polymer of glucose
1. Carbohydrates (a.k.a sugars or saccharides) (Fig. 2.15)
Monosaccharide. Exists as a single molecule Ex. Glucose C6H12O6 Disaccharide. 2 Monosaccharides joined by a covalent bond Ex. Sucrose (table sugar): Glucose + fructose Polysaccharide A polymer of several monosaccharides (hundreds to thousands) joined together by covalent bonds Ex. Starch and cellulose are polymers of glucose
Monosaccharide. Exists as a single molecule
Ex. Glucose C6H12O6
Disaccharide. 2 Monosaccharides joined by a covalent bond
Ex. Sucrose (table sugar): Glucose + fructose
Polysaccharide A polymer of several monosaccharides (hundreds to thousands) joined together by covalent bonds
Ex. Starch and cellulose are polymers of glucose
Ex. Glucose is a good source of energy and carbon for anabolic reactions that produce cellular components during growth Ribose is a 5-carbon monosaccharide that is a component of RNA
Glucose is a good source of energy and carbon for anabolic reactions that produce cellular components during growth
Ribose is a 5-carbon monosaccharide that is a component of RNA
2. Lipids
Nonpolar. Not soluble in water ("oil and water don't mix") 3 major classes 1) Triglycerides (Fig. 2.18) Composed of glycerol (a carbohydrate) linked to 3 long-chain fatty acids Used by cell to store energy
Nonpolar. Not soluble in water ("oil and water don't mix")
3 major classes
1) Triglycerides (Fig. 2.18)
Composed of glycerol (a carbohydrate) linked to 3 long-chain fatty acids Used by cell to store energy
Composed of glycerol (a carbohydrate) linked to 3 long-chain fatty acids
Used by cell to store energy
2) Phospholipids (Fig. 2.19) Fat with phosphate group substituted in place of 1 fatty acid Negative charge of phosphate interacts with polar water molecules Major component of cell membrane Interactions of the hydrophobic (nonpolar) fatty acid chains with each other and the hydrophilic (polar) phosphate with water are responsible for formation of the bilayer structure of membranes.
2) Phospholipids (Fig. 2.19)
Fat with phosphate group substituted in place of 1 fatty acid Negative charge of phosphate interacts with polar water molecules
Fat with phosphate group substituted in place of 1 fatty acid
Negative charge of phosphate interacts with polar water molecules
Major component of cell membrane
Interactions of the hydrophobic (nonpolar) fatty acid chains with each other and the hydrophilic (polar) phosphate with water are responsible for formation of the bilayer structure of membranes.
3) Steroids (See Fig. 2.20) Four fused carbon rings linked to a side chain Component of cell membrane of plants, animals and some microorganisms
3) Steroids (See Fig. 2.20)
Four fused carbon rings linked to a side chain Component of cell membrane of plants, animals and some microorganisms
Four fused carbon rings linked to a side chain
Component of cell membrane of plants, animals and some microorganisms
3. Proteins. Polymers of amino acids
General structure of an amino acid
The R groups of the amino acids present in a protein determine its properties and its interactions with other cellular components 20 different R groups = 20 different amino acids (Table 2.5) R groups may be nonpolar, polar, acidic or basic
The R groups of the amino acids present in a protein determine its properties and its interactions with other cellular components
20 different R groups = 20 different amino acids (Table 2.5) R groups may be nonpolar, polar, acidic or basic
20 different R groups = 20 different amino acids (Table 2.5)
R groups may be nonpolar, polar, acidic or basic
Peptide bond: covalent bond that links amino acids together to form a protein. (See Fig. 2.21)
Proteins consists of many (often several hundred) amino acids linked together by peptide bonds.
Another name for a protein is a polypeptide.
Protein Structure
1. Primary structure. Order of occurrence of amino acids in a polypeptide Ex. Methionine-Valine-Serine-Aspartic acid-Lysine-......etc. 2. Secondary structure. Conformation of the polypeptide backbone Helix or sheet 3. Tertiary structure. Overall shape of completely folded polypeptide 4. Quaternary structure. Combination of 2 or more polypeptides Only proteins consisting of more than one polypeptide have this structure
1. Primary structure. Order of occurrence of amino acids in a polypeptide
Ex. Methionine-Valine-Serine-Aspartic acid-Lysine-......etc.
2. Secondary structure. Conformation of the polypeptide backbone
Helix or sheet
3. Tertiary structure. Overall shape of completely folded polypeptide
4. Quaternary structure. Combination of 2 or more polypeptides
Only proteins consisting of more than one polypeptide have this structure
Ex. High temperature High or low pH Chemicals (Ex. alcohol, acids, bases)
High temperature High or low pH Chemicals (Ex. alcohol, acids, bases)
High temperature
High or low pH
Chemicals (Ex. alcohol, acids, bases)
Classification of proteins
1) Structural proteins Components of cell structures Ex. flagella for motility (movement) 2) Enzymes Catalysts that speed up metabolic reactions in cells Ex. X + Y ----------------> X-Y Too slow to support life Enzymes increase reaction rates by thousands to millions of times, making life possible 3) Other Regulatory proteins. Control expression of genetic information and metabolism Receptors. Sense environmental stimuli Transport proteins. Move substances across the cell membrane as they enter or exit the cell Antibodies Produced by immune system of higher organisms (not produced by microorganisms, but inhibit or prevent infections by pathogenic microorganisms)
1) Structural proteins
Components of cell structures Ex. flagella for motility (movement)
Components of cell structures
Ex. flagella for motility (movement)
2) Enzymes
Catalysts that speed up metabolic reactions in cells Ex. X + Y ----------------> X-Y Too slow to support life Enzymes increase reaction rates by thousands to millions of times, making life possible
Catalysts that speed up metabolic reactions in cells
Ex. X + Y ----------------> X-Y
Too slow to support life
Enzymes increase reaction rates by thousands to millions of times, making life possible
3) Other
Regulatory proteins. Control expression of genetic information and metabolism Receptors. Sense environmental stimuli Transport proteins. Move substances across the cell membrane as they enter or exit the cell Antibodies Produced by immune system of higher organisms (not produced by microorganisms, but inhibit or prevent infections by pathogenic microorganisms)
Regulatory proteins. Control expression of genetic information and metabolism
Receptors. Sense environmental stimuli
Transport proteins. Move substances across the cell membrane as they enter or exit the cell
Antibodies
Produced by immune system of higher organisms (not produced by microorganisms, but inhibit or prevent infections by pathogenic microorganisms)
4. Nucleotides and nucleic acids
Nucleotides
Three components (Fig. 2.23) 1) Organic base that contains nitrogen (Adenine, Guanine, Cytosine, Thymine or Uracil) 2) Five carbon sugar (Ribose or Deoxyribose) 3) Phosphate group(s)
Three components (Fig. 2.23)
1) Organic base that contains nitrogen (Adenine, Guanine, Cytosine, Thymine or Uracil) 2) Five carbon sugar (Ribose or Deoxyribose) 3) Phosphate group(s)
1) Organic base that contains nitrogen (Adenine, Guanine, Cytosine, Thymine or Uracil) 2) Five carbon sugar (Ribose or Deoxyribose)
3) Phosphate group(s)
Two main functions in cells: 1) Source of energy Ex. Adenosine triphosphate (ATP) (Fig. 2.27)
Two main functions in cells:
1) Source of energy Ex. Adenosine triphosphate (ATP) (Fig. 2.27)
1) Source of energy
Ex. Adenosine triphosphate (ATP) (Fig. 2.27)
2) Building blocks of nucleic acids
Nucleic acids
Polymers of nucleotides (Fig. 2.23) Used for storage and expression of genetic information Sugar-phosphate backbone links nucleotides together Nitrogen bases extend out from the sugars
Polymers of nucleotides (Fig. 2.23)
Used for storage and expression of genetic information
Sugar-phosphate backbone links nucleotides together Nitrogen bases extend out from the sugars
Sugar-phosphate backbone links nucleotides together
Nitrogen bases extend out from the sugars
1 Deoxyribonucleic acid (DNA) -Blueprint for synthesis of all proteins needed by the cell Consists of two strands (Fig. 2.23 and 2.25) Held together by hydrogen bonds between nitrogen bases of opposite strands Nitrogen bases: Adenine, Thymine, Guanine, Cytosine (no Uracil) (Fig. 2.24) A of one strand hydrogen bonds only to T of the adjacent strand G hydrongen bonds only to C 5-C sugar is deoxyribose (Fig 2.24) 2. Ribonucleic acid (RNA) -Involved in expression of the information in DNA during protein synthesis Consists of a single strand Nitrogen bases: A, Uracil, G, C (no T) 5-C sugar is ribose (Fig. 2.24)
1 Deoxyribonucleic acid (DNA) -Blueprint for synthesis of all proteins needed by the cell
Consists of two strands (Fig. 2.23 and 2.25) Held together by hydrogen bonds between nitrogen bases of opposite strands Nitrogen bases: Adenine, Thymine, Guanine, Cytosine (no Uracil) (Fig. 2.24) A of one strand hydrogen bonds only to T of the adjacent strand G hydrongen bonds only to C 5-C sugar is deoxyribose (Fig 2.24)
Consists of two strands (Fig. 2.23 and 2.25)
Held together by hydrogen bonds between nitrogen bases of opposite strands
Nitrogen bases: Adenine, Thymine, Guanine, Cytosine (no Uracil) (Fig. 2.24)
A of one strand hydrogen bonds only to T of the adjacent strand G hydrongen bonds only to C
A of one strand hydrogen bonds only to T of the adjacent strand
G hydrongen bonds only to C
5-C sugar is deoxyribose (Fig 2.24)
2. Ribonucleic acid (RNA) -Involved in expression of the information in DNA during protein synthesis
Consists of a single strand Nitrogen bases: A, Uracil, G, C (no T) 5-C sugar is ribose (Fig. 2.24)
Consists of a single strand
Nitrogen bases: A, Uracil, G, C (no T)
5-C sugar is ribose (Fig. 2.24)
DNA -----> RNA ----->Protein
The information is encoded as a sequence of the 4 nitrogenous bases (A, T, G, C) Ex. T-A-T-C-G-T-A-A-C-A------etc. determines the sequence of amino acids of a protein
The information is encoded as a sequence of the 4 nitrogenous bases (A, T, G, C)
Ex. T-A-T-C-G-T-A-A-C-A------etc. determines the sequence of amino acids of a protein
Summary of DNA and RNA properties
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