Name 3 reasons carbohydrates (sugars) are important.
1) Source of energy for driving cellular metabolism
2) Chemical Signaling
3) Structure – insect exoskeleton, cellulose
Name 2 reasons lipids are important.
1) Lipids or long chain hydrocarbons are used for structure (relatively small)
2) Collections of lipids form membranes in an aqueous environment (van der Waals, hydrophylic/hydrophobic interactions)
True or False: Macromolecules as covalent bonds do not hold adjacent lipids together.
False
What do membranes do in cells?
Membranes separate cells and make compartments within cells.
Why are proteins important?
Proteins make up the molecular machinery of cells and they are polymers of 21 different amino acids.
Proteins make up the molecular machinery of what kinds of cells?
F) All of these
Why are nucleic acids important?
They carry information.
What are nucleic acids made of?
Nucleotides
How many different nucleic acids are used in the coding of DNA and RNA?
4
What are two types of codes formed from different nucleic acids?
DNA and RNA
Define Stereoisomers
Molecules with the same chemical composition but different arrangement of atoms about an
asymmetric, or chiral, carbon
In a biological system with two stereoisomers, what is the status of these stereoisomers?
Most commonly one stereoisomer is active within a system and the other is not.
Dextro (D) represents what kind of stereoisomer?
One that is active in a biological system.
Levo (L) represents what kind of stereoisomer?
One that is inactive in a biological system.
What are the roles of sugar?
1) Structure (cellulose)
2) Storage/energy
3) Signaling
What is the basic unit of a sugar?
Monosaccharide
What is the name of a monosaccharide with 6 carbons?
Hexose
What is the name of a monosaccharide with 5 carbons?
Pentose
What is the name of a monosaccharide with 4 carbons?
Tetrose
What is the name of a monosaccharide with 3 carbons?
Triose
What are the two chemical categorizations of monosaccharides?
Aldose and Ketose
Give an example of an Aldose.
D-Glucose
Give an example of a Ketose.
D-Fructose
How many carbons does Glucose have?
6
What is the structure of ribose?
Furan ring structure
How many carbons does Ribose have?
5
What are the 2 forms of ribose?
Ribose and Deoxyribose
Glucose + Glucose = ?
Maltose
What kind of linkage between glucose molecules forms Maltose?
–1,4 glycosidic linkage
The formation of Maltose from 2 Glucose molecules is what type of reaction?
Condensation Reaction
What is sucrose?
Table Sugar
What is Lactose?
Milk Sugar
How is lactose formed?
–1,4 glycosidic linkage
What are polysaccharides?
Very large, complex molecules made up of sugars.
What causes the complexity of polysaccharides?
The ability of monosaccharides to bind in many ways
What is amylose?
Part of starch
How is amylose formed?
Multiple –1,4 glycosidic linkages
What is Chitin?
Insect Exoskeleton
How is chitin formed?
Multiple –1,4 glycosidic linkages
How is cellulose formed?
Multiple –1,4 glycosidic linkages
True or False: Cellulose is digestible by humans.
False
How is glycogen formed?
Multiple –1,4 glycosidic linkages
True or False: Glycogen is digestible by humans.
True
How are polysaccharides stored?
They are stored in muscles and liver as secondary Energy storage.
Why are polysaccharides stored in muscles?
For immediate use in muscles
Why are polysaccharides stored in the liver?
For distribution systemically
Name the sources of starch.
Potatoes and Corn
Name the uses of starch.
Food and Clothing
Name the sources of cellulose.
Wood and Cotton
Name the uses of cellulose.
Paper and Clothing
Name the source of carrageenan.
mycophyta (algae)Name the sources of starch.
Name the use of carrageenan.
Food
Name the source of agar.
mycophyta (algae)
Name the uses of agar.
Microbiology and Food
Name the source of dextran.
Corn
Name the uses of dextran.
Food and Medicine
Name the source of agarose.
mycophyta (algae)
Name the use of agarose.
Biochemistry
Name the source of xanthan gum.
X. campestris
Name the uses of xanthan gum.
Food, industrial chemical, and oil field drilling
Define Lipids
Category of hydrophobic compounds that are insoluble in water but soluble in nonpolar solvents. Present in nonaqueous phases of cells
Define Fats
Combined lipids that serve as biological energy storage molecules.
Define Steriods
Hormones that are regulators/stimulators of many cellular functions at low concentrations. Complex in structure.
What is the main component of lipids?
Fatty Acids
A lipid typically consists of how many carbons?
12-20 Carbons
What are the 2 components of a fatty acids?
A strongly nonpolar hydrocarbon chain and a polar terminal group.
What does it mean if a lipid/fatty acid is saturated?
It means it has the max number of H atoms and is linear.
What does it mean if a lipid/fatty acid is unsaturated?
It means there are some C=C bonds present. The chain is kinked and has a cis/trans configuration.
Which is more saturated? Lard or Olive Oil?
Lard is more saturated. Lard is 37.7 % saturated while olive oil is only 2.9 % saturated. However, olive oil is considered very saturated so Lard is even more saturated than that.
What is the hydrogenation of oils?
Add H2 to liquid oil under pressure.
Why do we hydrogenate vegetable oils?
a) So it does not turn rancid as fast (improve shelf life)
b) To make them solid/semisolid at room temperature
c) To increase the temperature at which they
burn
d) All of these
e) None of these
d) All of these
Fatty acids naturally occur in which form primarily?
a) cis
b) trans
a) cis
Which orientation of the H atoms occurs as a result of the hydrogenation process?
a) cis
b) trans
b) trans
What is a phospholipid?
Its an important component of cell membranes.
What are phospholipids composed of?
2 Fatty Acids, glycerol, 1 Phosphate, and 1 Choline or Other Group
What is this structure?
Phosphatidic Acid
What is this structure?
Phosphatidylserine
What are the two types of structures commonly formed by phospholipids?
phospholipid double Layers and single layer micelles
What are triglycerides?
Fats
What is the equation for fats/triglycerides?
Fats = 1 Glycerol + 3 Fatty Acids
(The fatty acids can be different.)
What is the precursor to steriods?
Lipids
What are naturally occuring steroids?
B) hormones
Where does cholesterol occur?
In membranes.
What is the purpose of the steroid Cortisone?
anti-inflammatory
What is this structure?
Cholesterol
(precursor for many steroids including testosterone and cortisone)
What is this structure?
Cortisone
(an adrenocortical hormone)
What is this structure?
Estrone
(a female sex hormone)
What is this structure?
Testosterone
(a male sex hormone)
What is this structure?
Progesterone
What are the building blocks of polypeptides and protein?
Amino Acids
Which amino acid isomer is found in proteins and is most common.
L isomer
Which group varies to form different amino acids?
The R Group
Which form of amino acids are found primarily in bacterial cell walls?
D form
Ionization states of an amino acid depend on
C) pH
How many amino acids are found in proteins?
21 amino acids
How many amino acids are encoded in the human genome?
All 21 of the amino acids which are found in proteins
How many amino acids are essential to humans?
9 amino acids
Name the amino acids essential to humans.
Histidine, Isoleucine, Leucine, Lysing, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine
What are polymers formed of amino acids?
polypeptides/proteins
If a polypeptide chain ends with a Nitrogen, it is said to be
a) amino terminus
b) carboxy terminus
a) amino terminus
If a polypeptide chain ends with a Carbon, it is said to be
a) amino terminus
b) carboxy terminus
b) carboxy terminus
Polypeptides/proteins are formed via what reaction?
A condensation reaction
What kind of bond forms between amino acids?
A peptide bond
How many levels of protein structure are there? What are they?
4 levels
Primary, Secondary, Tertiary, and Quaternary
What is primary protein structure?
Sequence of amino acids (ie Leu, Val, Cys, Met)
Held together by covalent bonds between amino acids (peptide bond, amide linkage)
Proteins synthesized by cells only have peptide bonds and nothing synthesized onto R groups. Protein production only makes the covalent bonds between amino acids.
What is secondary protein structure?
Results from H bonding between amino acid residues on the same peptide backbone.
Bonding is between N and O.
Common examples of secondary structure are α-helix, β-pleated sheet, triple α-helix (collagen)
What is tertiary protein structure?
Results from interactions between R (and other) groups widely separated on the polypeptide chain.
Disulfide bonds S-S (Cys-Cys)
Covalent bonds
Hydrophobic-hydrophylic interactions
Also results from interactions between α-helix and β-pleated sheet
Which factors are included in tertiary structure?
Surface Properties, Catalytic Activity, Chemical Stability, Shape, and Mechanical Strength
Which protein structure level is dependent on how the protein is synthesized?
Tertiary
How are procaryotes synthesized?
This type of protein is synthesized in the cytoplasm and tertiary structure develops as it is made. No ER for posttranslational modification.
How are eucaryotes synthesized?
Rough ER may tether protein end while it is being made. Modifications can happen while the protein is held by the ER; these can effect structure.
What is quaternary protein structure?
Results from interactions between more than one polypeptide chain
2 or more chains
Many proteins have multiple subunits
True or False: The majority of proteins are pure.
False. The majority of Proteins are not “pure” but are conjugated to some other molecule
What is the name of the cellular process used to modify proteins into conjugates after they have been made?
posttranslational modification
What is is the moiety conjugated to the protein?
The Prosthetic Group
What are the classes of modified proteins?
Lipoproteins, Glycoproteins, Phosphoprotein, Hemoproteins, Flavoproteins, and Metalloproteins
What is the prosthetic group for lipoproteins?
lipids
What is the prosthetic group for glycoproteins?
oligosaccharides
What is the prosthetic group for phosphoproteins?
phosphate
What is the prosthetic group for hemoproteins?
Iron Porphyrin
What is the prosthetic group for flavoproteins?
Falvin Nucleotides
What is the prosthetic group for metalloproteins?
Iron and Zinc
Give an example of lipoproteins.
B-lipoprotein of blood
Give an example of glycoproteins.
Gamma Globulin
Give an example of phosphoproteins.
Protein Kinase C
Give an example of hemoproteins.
Hemoglobin
Give an example of flavoproteins.
Sucinate dyhydrogenase
Give an example of metalloproteins.
Alcohol dehydrogenase
What are antibodies?
A specific class of proteins produced by B cells of the blood.
There are many types of antibodies but what is most common example in protein chemistry?
IgG
Antibodies are made of how many chains?
4 chains (2 heavy chains and 2 light chains)
There are variable regions on the ends of antibodies made for what purpose?
To specifically bind foreign objects
Proteins in which categories are commercially produced?
Structural, Enzymes, Transport, Nutrient, Contractile, Defense, Regulatory, and Inhibitors
Name some structural proteins.
Keratin (skin)
Fibroin (silk)
Collagen (tendons & ligaments)
Elastin (joints)
Proteoglycans (cell walls)
Name some enzymatic proteins.
Trypsin (cleaves proteins)
DNA polymerase (makes DNA)
Cellulase (breaks down cellulose)
peroxidase (reagent)
Name some transport proteins.
Hemoglobin (transfers oxygen)
Na/K ATPase (moves K and Na)
Name some nutrient storage proteins.
Ovalbumin (egg)
Casein (milk)
Name some contractile or motile proteins.
Actin (muscle)
Myosin (muscle)
Tubulin (cytoplasm)
Name some defense proteins.
Venom proteins (for producing antivenom)
Ricin and others (biodefense)
Name some regulatory proteins.
Human Growth Hormone
Insulin
Cytokines (cancer treatment)
Protein Kinases (signal transduction)
Insulin like growth factor
Other hormones (testosterone, estrogen…)
Name some inhibitor proteins.
Trypsin inhibitor (reagent)
HIV protease inhibitor
Name some therapeutic agent proteins.
Antibiotics (many types)
Immunizations
What does it mean for a protein to denature?
It means that one of the levels of structure has been altered relative to the normal functional state
Protein function is most dependent on what?
Function is most dependent on quaternary and tertiary structure which both depend on secondary and primary structure
Why is it important to preserve the integrity of the protein through processing and separation?
Because a denatured protein generally loses function
What force can denature a protein?
C) All of these
What are the monomers of DNA?
Nucleotides
What is the general formula for DNA?
DNA = sugar + base + phosphate
(Sugars include ribose and deoxyribose)
What are the two types of bases in DNA?
Purine (double ring) and Pyrimidine (single ring)
What are the three types of pyrimidines?
Cytosine (C), Thymine (T), and Uracil (U)
What are the two types of purines?
Adenine (A) and Guanine (G)
What is the chemical formula for phosphate?
PO4
What carbon of the sugar does the nitrogenous base attach to in DNA?
Carbon 1
What carbon of the sugar does the phosphate attach to in DNA?
Carbon 5
The nitrogenous base uracil (U) is only present in what?
RNA
True or False: Bases join adjacent nucleotides on the same DNA polymer.
False
What is the structure of DNA?
Double Helix
What are the 3 types of RNA?
Transfer, ribosomal, and messenger
True or False: The Phosphate-Sugar backbone faces the inside of DNA.
False
In DNA Adenine (A) pairs with
A) Thymine (T)
In DNA Cytosine (C) pairs with
D) Guanine (G)
What does the order of bases do in the sense strand of DNA?
Carries the genetic code
What does the order of bases do in the antisense strand of DNA?
Act as a placeholder
Uracil (U) is a substitute for what nitrogenous base in RNA?
Thymine (T)
In RNA Uracil (U) pairs with
A) Adenine (A)
Where is mRNA formed?
In the nucleus from a DNA template
What is the structure of mRNA?
single stranded
What is the purpose of mRNA?
Caries the code for a specific amino acid sequence in the order of nucleotides
Moves to cytoplasm to act as a “template” for producing and amino acid sequence
What is a transcription of the DNA nucleotide sequence?
Messenger RNA (mRNA)
What is the structure of tRNA?
single stranded
What is the purpose of tRNA?
Carries specific amino acids for assembly into a protein
What are ribosomes?
organelles that are the site of protein synthesis
What is the purpose of rRNA?
Use m-RNA and t-RNA to create the specific amino acid sequence of a protein
–1,4 glycosidic linkage