Chapter 12 Flashcards
Notability
1
Q
Enantiomers have
A
Identical chemical & physical properties, except how they interact with other chiral molecules & how they interact with polarized light
2
Q
Stereocenters are the
A
Single bond atoms that have 4 different groups
3
Q
Light is
A
Electromagnetic radiation
4
Q
Light waves are transverse waves that are
A
Composed of alternating electrical & magnetic fields which are at right angle to each other & perpendicular to movement
5
Q
What has optical activity?
A
Chiral molecules
6
Q
What is Dextrorotatory?
A
Enantiomers that rotate polarized light in a clockwise direction
+
7
Q
What is Levorotatory?
A
Enantiomers that rotate polarized light in a counterclockwise direction
- (minus)
8
Q
Are racemic mixtures optically active?
A
No because the rotation of the Levorotatory & Dextrorotatory cancel each other out
9
Q
Biomolecules fall into what 4 categories?
A
Carbs
Proteins
Nucleic acid
Lipds
10
Q
Carbs/ aldehydes/ketones are
A
Used primarily for energy storage & structure
11
Q
Proteins are polymers of amino acids which contain an
A
Amine & carboxylic acid functional group
12
Q
Proteins serve as
A
Structural elements & chemical catalysts that make life possible
13
Q
Nucleic acids are polymers of sugar joined together by
A
Phosphate Ester linkages in which they contain aromatic amines
Are the architects of proteins
14
Q
Lipids are
A
Biomolecules that are more soluble in organic solvents such as ether
Composed of nonpolar hydrocarbon functional groups
15
Q
What is the most common monosaccharide?
A
Glucose
16
Q
Disaccharides are composed of
A
2 monosaccharides joined by an acetal or ketal link (glycoside bond)
(table sugar)
Common: Sucrose, Maltose & Lactose
16
Q
Monosaccharides are sugars that are
A
Not easily broken down into simple sugars
17
Q
A D sugar will
A
Point to the right
(second to last)
18
Q
What is the most common ketohexose
A
Fructose
19
Q
What is the most common D-Aldohexoses?
A
Glucose
20
Q
What are the most important D-Aldopentose?
A
Ribose
Deoxyribose
21
Q
Monosaccharides have functional groups that are either a
A
Ketone or Aldehyde
22
Q
Aldehyde reacts with alcohols to form
A
Hemiacetals
23
Q
What is always found as pyranose?
A
Glucose
24
Ketones react with alcohols to form
Hemiketals
25
Fructose is always found as
Furanose
25
A 6 membrane cyclic sugar is a
Pyranose
26
Can we digest starch?
Yes because it is composed of alpha glycosidic bonds
27
What are 2 common polysaccharides?
Starch & Cellulose
28
Cellulose is composed of
Beta glyosidic bonds we cannot digest
29
Roles of Lipids
Hydrophobic
Soluble in organic solvents
Energy storage
Maintains cell membranes
30
Glycerides are composed of
Glycerin & fatty acids
31
Triglycerides have
3 fatty acid residues attached to the glycerin backbone
32
Fatty acids are long chain
Carboxylic acids
33
Saturated fatty acids have
Carbon chains
Contain only carbon to carbon single bonds
34
Unsaturated fatty acids have
At least one carbon to carbon double bonds
35
Triglycerides are
Triesters of glycerol & 3 fatty acids
Called fats or oils
36
Fat s& oils are
Not pure substances
37
What is Saponification?
Triglycerides + strong base= fatty acid metal salts
38
Phospholipids are
Common in cellular membrane due to surfactant properties
39
Phospholipid structure
Hydrophobic tail
Hydrophilic head
40
Steroids are characterized by the
Steroid ring system which consist of 3-6 member rings fused to a 5 member ring
41
Proteins are more
Dense than lipids
42
Cholesterol is an essential component of
Cellular membranes-it is transporting blood as a lipoprotein
43
High density lipoproteins have a
Greater protein to lipid ratio
44
High levels of LDL are
Indicative of potential heart problems
LDL more likely to release cholesterol
44
Prostaglandins are
Powerful but short lived;
Synthesized from the unsaturated fatty acid & arachidonic acid
45
What is produced during carb metabolism?
ATP & Acetyl CoA
46
What is the main role of Acetyl CoA?
A carrier of the acetyl group
Carbs are converted to glucose which feeds into the glycolysis pathway
47
Glycolysis converts glucose to
Pyruvic acid which under anaerobic conditions is reduced to lactic acid & under aerobic conditions is converted into Acetyl CoA as well as NADH which is essential in energy creation
48
49
The Kreb cycle is the
Principle aerobic energy producing pathway of the body
Most energy produced in this cycle is in the form of NADH
49
Fatty acids are cleaved from
Triglycerides & metabolized through beta oxidation creating Acetyl CoA & NADH
Acetyl CoA feeds into the Krebs cycle where 1 molecule of glucose can drive 2 rounds of Kreb cycle
1 molecule of Stearic acid can drive 9
50
Proteins are
Polymers of amino acids joined together by peptide bonds
51
Proteins are
Enzymes, hormones & HGB
52
When 2 amino acids are joined together, its called a
Dipeptide
(3=tripeptide; many =polypeptide)
53
Amino acids contain an organic functional group, a____ & a _____
Amine group (unique side chain)
Carboxylic group
54
The identity of the amino acid is determined by the
Side chain
55
All amino acids are
Chiral as well as proteins
56
What are Zwitterions?
Ions containing 2 functional groups that possesses both positive & negative electrical charges
(neutral)
Amphiprotic species
Behave as an acid or base
Amino group is a proton acceptor (base)
Carboxyl group is a proton donor (acid)
57
The Isoelectric point is when the net charge on the amino acid is
Zero
Point is the pH at which we would change from a negative to a positive form
pH <6=average charge on glycine molecules is positive
pH>6= negative
58
What is electrophoresis?
Using electrical fields to separate amino acids on the basis pf their electrical charge & molecular weightA
When applied to nucleic acid samples= DNA fingerprinting
59
A peptide bond is an
Amine bond formed between the amino group of 1 amino acid & the carboxyl group of another amino acid
Amino acids has an orientation & the polypeptide chain has a direction (free amino group (end terminus)/free carboxyl group (C terminus) on each side)
60
How many total amino acids in HGB?
574
61
Configuration of protein structure is based on
Primary
Secondary
Tertiary
Quaternary
62
The primary structure for protein is a
Sequence of amino acids in the peptide chain; this sequence determines the function of the proteins
Small changes in Amino acids can cause a protein to be completely different & possibly nonfunctional
63
Secondary structure is based on
Hydrogen bonding & the interaction between the amine & carboxyl group causing folding of the shape
Alpha Helix (coil twists clockwise/right) & Beta Pleated Sheet
64
Tertiary structure is the
Overall 3-D structure of the polypeptide; due to interactions between R groups
R group interaction includes hydrogen bonding, ionic bonding, dipole-dipole interactions & London dispersion
65
Denaturing of proteins involves the
Disruption & possible destruction of both the secondary & tertiary structures
Not strong enough to break the peptide bonds, so primary structure remains the same
Disrupts the alpha helix & beta sheets & coils it into a random shape
Causes precipitation or coagulation
66
Without enzymes, metabolic reactions would be
Slow
67
Enzymes bind
Substrates at key locations in the structure that are called Active Sites
Highly specific & only bind certain substrates
(hold 2 amino acids together)
68
The main biopolymers in the body are
Protein
Carbs
Nucleic Acids
69
Nucleic acids are
Polynucleotides or polymers of nucleotides
70
Each nucleotide is a
Nitrogen containing aromatic base attached to a pentose sugar thats attached to a phosphate group
71
Each nucleic acid contained how many possible nitrogen containing bases?
4 or 5
Adenine
Guanine
Thymine
Cytosine
Uracil
72
DNA is a
Polymer of the 4 nucleotides adenine, cytosine, guanine & thymine
73
Adenine always pairs with
Thymine
74
Guanine always pairs with
Cytosine
75
The double stranded DNA forms the
Alpha Helix structure
76
RNA helps process
Chemical reactions in the body
Only single stranded
Contains Uracil instead of thymine
Facilitated translation of DNA & proteins
Messenger between DNA & ribosomes
(hydrogen bonding)
77
DNA stores
Genetic information & its located inside the nucleus where RNA transfers genetic information & is located outside the nucleus
78
What are the 3 main RNA types?
Messenger RNA
Transfer RNA
Ribosomal RNA
79
Messenger RNA is
Synthesized in the nucleus directly from DNA
Formed by a transcription from DNA
Provides a template for protein synthesis
80
RNA polymerase
Catalyzes the transcription process
81
Transfer RNA is known as
Soluble RNA
Can diffuse through ribosomes
Carries specific amino acid which becomes important in translation
Defects can cause various diseases
82
Transcription is the process of
Forming a complementary messenger RNA strand from DNA
Occurs in the cell nucleus
83
Helicase unwinds & breaks the
Double helix of DNA apart, allowing RNA nucleotide bases to form complementary hydrogen bonds
84
How is the messenger RNA formed?
Once RNA bases are bound by hydrogen bonding through the DNA phosphate ester link is formed between the 2 RNA nucleotides
85
TransLation is the process of
Pairing transfer RNA to messenger RNA
86
Each group of 3 bases in messenger RNA constitutes a
Codon
87
Messenger RNA sequence happens inside the
Ribosome
88
The transfer RNA binds to the messenger RNA & the
Amino acids are linked & the transfer RNA is separated & leaves the ribosome
89
A drug will exert its effect on
Biological systems with a specific receptors
90
Drug interactions with receptors
Change the state of the receptor & then it has its physiological effects
91
Endogenous ligands occur
Within the body & can bind to receptors
Can be NT, hormones or a drug
Binding site is called Active Site
92
What is affinity?
The strength of interaction between a receptor & its ligand
Higher-tighter interaction with a receptor
Typically determined by the percentage of receptors bound by a drug
93
Efficacy is the
Ability of a drug to elicit a response & depends on the affinity of a ligand for a receptor as well as the cellular response that occurs by activating that receptor
94
Potency is a
Measure of the amount of drug needed to produce a given effect
95
Agonist drugs initiate
Physiological response
96
Antagonists bind to a receptor &
Prevent the receptor from functioning normall
97
A full agonist causes the
Maximum physiological response
98
Partial agonist binds to a receptor &
Only a portion of the pharmacologic response results
No addition of a partial will result in maximum activation
99
Antagonists often block the
Binding of an agonist, preventing the action of the receptor
Called inhibition & can be competitive or Non-competitive
100
Signal transduction is the process of
Perceiving a chemical signal
101
What are the 4 mechanisms of signal transduction?
Ligand combined with an intracellular receptor
Transmembrane receptor can alter intracellular enzymatic
Receptor gated ion channel
G-protein coupled
102
How does the G protein activation work?
GTP binds to alpha subunit
Alpha subunit will diffuse through the cytoplasm, causing action on a target protein
Alpha subunit causes 2nd messenger events within the cell
Will cause protein activation, synthesis, glucose metabolism or the release of more second messengers
103
What is necessary to ensure molecular interactions between the ligand & the receptor?
Pharmacophores
104
Ionic bonds are
Groups that donate or accept hydrogen bonds or groups that form hydrophobic interactions
