Unit 1: Chemistry of Life - Functional Groups, Carbs, Lipids, and Proteins Flashcards
Functional Groups, Carbs, Lipids, and Proteins
Hydroxyl
-OH
Carbonyl
C double bonded to an O on top (CO)
Amino
H-N-H
Carboxyl
C double bonded to O and single bonded to OH (COOH)
Phosphate
P double bonded to one O and three single bonds to O’s (POOOO)
Sulfhydryl
SH
Methyl
C with single bonds to H (CH3)
All functional groups except methyl are…
Polar
Methyl group is…
Nonpolar
How many valence electrons does Carbon have?
4
What does carbon allow for creating?
Large molecules, or macromolecules
Which elements are found in all organic matter?
Carbon and hydrogen
How many major macromolecules are there?
4
What are the 4 major macromolecules?
Carbohydrates, lipids, proteins, nucleic acids
Function of carbohydrates
Used for energy and make up the cell walls of plants and prokaryotes
Are carbs polar or nonpolar?
Polar
What elements are carbs made up of?
C, H, O
Since carbohydrates are polar and dissolve in water, they can’t do what?
Go through the cell membrane without a transporter
Lipids contain which elements?
C, H, O
Which two groups of macromolecules contain the same elements?
Carbs and lipids
Are lipids polar or nonpolar?
Nonpolar (think oil doesn’t mix with water)
Proteins are made up of which elements?
C, H, O, N
Are proteins polar or nonpolar?
Polar
Nucleic acids are made up of which elements?
C, H, O, N, P
Are nucleic acids polar or nonpolar?
Polar
The only macromolecule that is nonpolar is…
Lipids (think oil)
Define monomer
Single molecule
Define polymer
2 or more molecules linked together
How are polymers synthesized (made)?
Dehydration synthesis
What is dehydration synthesis?
Building polymers with the removal of water
In a dehydration synthesis reaction, what is the basic formula?
Monomer + monomer -> polymer + H2O
How are monomers synthesized?
Hydrolysis
What is hydrolysis?
Splitting/breaking down of polymer with the addition of water
In a hydrolysis reaction, what’s the basic formula?
Polymer + H2O -> monomer + monomer
Hydrolysis and dehydration synthesis reactions are…
Opposites/switched reactions
Why are functional groups important?
Functional groups influences the way a macromolecule reacts, especially how it reacts with water (electronegative, polar, nonpolar, etc)
What is the monomer of a carbohydrate?
Monosaccharides
What’s the ratio of hydrogens to oxygens in carbohydrates?
2:1
When ordering carbohydrates, which direction do you go in?
1 is on the right middle of the ring. Then continue with 2, 3, 4, 5, and 6 around clockwise
Example of a dehydration synthesis reaction with glucose
C6H12O6 + C6H12O6 -> C12H22O11 + H2O
What’s the common name for monosaccharides?
Simple sugars
6 carbon sugars are called…
Hexose sugars
5 carbon sugars are called…
Pentose suagrs
3 examples of hexose sugars
Glucose, fructose, galactose
2 examples of pentose sugars
Ribose, deoxyribose
In an alpha glucose molecule, the hydroxyl groups are facing…
BOTH downwards
In a beta glucose molecule, the hydroxyl groups are facing…
ONE upward and ONE downward
Trick to remember alpha and beta glucose
opposite of what it stands for:
alpha - above, beta - below
ACTUALLY alpha bottom, beta above and below
What’s differnet about alpha and beta glucose?
The direction the hydroxyl groups are facing
Disaccharides are…
2 monosaccharides bonded together by dehydration synthesis
What is the name of the covalent bond that joins a carbohydrate molecule to another group?
Glycosidic bond
A glycosidic bond is a ___ bond
Covalent
Glucose + glucose
Maltose + water
Glucose + fructose
Sucrose + water
Glucose + galactose
Lactose + water
Polysaccharides are…
3 or more monosaccharides bonded together by dehydration synthesis
3 types of polysaccharides
Starch, glycogen, cellulose
Starch monomer, linkage, shape, cell type, function, are humans able to break the bond
Alpha glucose, 1, 4 alpha glycosidic, branches, plant cell, provides energy by storing sugar in plants, yes humans can break bonds
Glycogen monomer, linkage, shape, cell type, function, are humans able to break the bond
Alpha glucose, 1, 4 alpha glycoside, branches, animal cell, provides energy by storing sugar in animals, yes humans can break the bonds
Cellulose monomer, linkage, shape, cell type, function, are humans able to break the bond
Beta glucose, 1, 4 beta glycosidic, arranged in compact, uniform, linear sheets, plant cell, makes up cell wall of plants, humans can’t break the bonds
Trick to remember which bonds humans can break
Humans eat starchy plants like sweet potato, glycogen stores sugar in humans - cellulose is plant cells only
Trick to remember which polysaccharides are beta be which are alpha
Animals/humans can break down = alpha
Why can’t humans break down cellulose?
Humans don’t have the enzymes to break down 1, 4 beta glycosidic linkage
What are the functions of carbohydrates?
Provide energy and used as a cell wall
The product of dehydration synthesis is a
Polymer
The product of hydrolysis is a
Monomer
How does the molecular formula of beta glucose compare to that of alpha glucose?
They’re the same
What’s the scientific name for starch?
Amylose
What does the ratio of hydrogen to oxygen look like in a lipid?
Greater than 2:1
Which element is more numerous in carbohydrates than it is in lipids?
Oxygen (Think carbs are polar, so they have more of the electronegative element)
How many types of lipids are there?
3
What are the 3 types of lipids?
Triglycerides, phospholipids, steroids
What’s another name for steroids?
Sterols
How many rings do sterols have?
4 rings (think boxing ring)
3 examples of sterols
Estrogen, testosterone, cholesterol
Glycerol is a…
3 carbon sugar
Triglycerides contain a…
Glycerol attached to 3 fatty acids (think tri means 3)
Saturated fats
No double bonds, stiff/solid at room temperature (butter)
Unsaturated fats
1 or more double bonds, liquid at room temperature (olive oil)
What’s the name of the bond that links the three fatty acids to glycerol?
Ester bond
Phospholipid contain…
A phosphate group (head), 2 fatty acids (tails), and a glycerol backbone
The phosphate group or head is
Polar (phosphate, p, polar)
The fatty acids or tails are
Nonpolar
The squiggly tail represents ____ while the straight tail represents ____
Unsaturated fats, Saturated fats
Phospholipids make up the…
Phospholipid bilayer of the cell membrane
Why must there be 2 layers of phospholipids in the cell membrane?
If there was only one layer, the nonpolar and hydrophobic tails would be facing the water, which can’t happen. That’s why you need a second inward layer with the polar head facing the water.
Phospholipids are amphipathic, meaning
They contain both polar and nonpolar regions
Functions of lipids
Protect internal organs, temperature regulation and insulation, make up the cell membrane, provide energy
What element distinguishes between lipids and proteins
Nitrogen
Proteins contain which elements?
C, H, O, N, sometimes S
Monomer of protein
Amino acids
Polymer of proteins
Polypeptide
For proteins, shape determines…
Function
Amino acid structure and sequences determines…
Protein shape
Describe amino acid structure
Left, amine group
Middle, H on top of C and R variable side change on bottom of C
Right, carboxyl group
The amine group is a
Base
The carboxyl group is a
Acid
A base is a proton
Acceptor
An acid is a proton
Donor
Trick to remember what donates and what accepts H+
Acid does not Accept
The R or variable side change of an amino acid is
Not an element, gives each amino acid it’s unique chemical properties
Primary structure amino acid formula
Amino acid + amino acid -> polypeptide + water
Primary structure meaning
Sequence of amino acids in a polypeptide chain
What is the significant bond in the primary structure of an amino acid?
Peptide bond between C and N
In a primary structure, the order of the amino acids is coded for by…
DNA
Secondary structure meaning
Folded patterns that forms due to hydrogen bonding of the polypeptide backbone
The two most common types of secondary structures are
Alpha helix (coiled) and Beta pleated sheets (like rhombuses in a line)
The secondary structure is caused by
Hydrogen boning between the H in the amino group of one amino acid and the O in the carbonyl group of another amino acid
After the primary structure, the carboxyl group turns into a
Carbonyl group, as the OH come off and turn to water
Tertiary structure meaning
Overall three dimensional structure or a polypeptide
The tertiary structure is caused by…
R-chain interactions
What kind of R chain interactions take place?
- Hydrogen bonding between R groups
- Covalent bonding, specifically the string disulfide bond which helps keep parts of the polypeptide together
- Ionic bonds (attracts R groups with opposite charges)
- Hydrophobic and hydrophilic interactions create clusters
Hydrophobic clusters are located…
Inside the folded polypeptide and away from water molecules on the outside
Hydrophilic clusters are located…
Outside the folded polypeptide clusters and near the water molecules
Quaternary structure of a protein definition
2 or more polypeptides combined
Example of quaternary protein structure
Red blood cells are made up of 3 different polypeptides
In a protein, shape or conformation determines what
Function
More specifically, in a protein, what determines interactions with other molecules?
R groups and charges
What are the 4 functions of a protein?
- Antibodies/antigens
- Receptors
- Muscle growth and contraction
- Enzymes/catalysts that speed up chemical reactions
If DNA is changed, the
Protein is changed
How many types of proteins are there?
2
What are the two types of proteins?
Globular and fibrous
Define globular proteins
Carry out chemical processes
Think of globular proteins as the
Doers
Define fibrous proteins
Structural proteins
What’s a common example of globular proteins?
Enzymes/catalysts
What’s a common example of fibrous proteins?
Cytoskeleton collagen
Enzyme
Or catalyst, speeds up chemical reactions
Substrate
Binds to the enzyme (what the enzyme works on)
Active site
Location where the substrate binds to the enzyme
Enzyme substrate complex
When the enzyme and substrate are bound
After every use, the enzyme…
Is the same and doesn’t change
Lock and key fit
1 substrate fits 1 enzyme and the fit matches perfectly (think triangle and triangle cutout)
Induced fit
Enzyme’s active site us flexible and changes shape slightly upon substrate binding to achieve the best fit (think triangle and slightly rounded triangle cutout)
Competitive inhibition
A molecule similar in shape to a substrate binds to an active site and inhibits the substrate from binding
Allosteric inhibition
A molecule binds to the allosteric receptor, which is located somewhere other than the active site, causing the active site to change the substrate to not fit anymore
What 3 factors affect enzyme activity?
- pH
- temperature
- substrate and enzyme concentration
As temperature increases,
Enzyme activity increases until optimal temperature. Then activity decreases
Denature
Changes shape
Why does denaturing occur?
Bonds in tertiary structure breaks and the bonds in the secondary structure can break
Why is it that a protein can refill after denaturing?
If the secondary and tertiary structures are broken, the protein can refill because the primary structure is still unchanged
pH is different
For different enzymes
1-6
Acidic
What is pH?
A measure of how acidic or basic something is
7
Neutral
How much more acidic is a pH of 5 than a pH of 7?
100x (base 10)
8-14
Basic
As substrate concentration increases
Enzyme activity increases and then levels off
Function of nucleic acids
- Store and transmit our hereditary information
- Code for production of proteins
Elements
C, H, O, N, P
Monomer for nucleic acids
Nucleotides
Polymers for nucleic acids
Nucleic acid, DNA, or RNA
How many parts does a nucleotide have?
3
What are the 4 nitrogenous bases?
Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
What are the parts of a nucleotide?
- Phosphate (circle phosphorus group)
- Pentose sugar (pentagon)
- Nitrogenous bases
How does a purine look different from a pyrimidine?
Purines have an extra, slightly smaller pentagon attached to the hexagon base
Think shorter word, longer molecule
Purines
Adenine and guanine
Pyrimidines
Cytosine and thymine
What base is different in DNA and RNA?
Uracil in RNA, thymine in DNA
What sugar is different in DNA and RNA?
Ribose in RNA, Deoxyribose in DNA
What is different in regards to the number of strands in DNA and RNA?
DNA is double stranded, RNA is single stranded
What’s unique about DNA?
It is anti-parallel
What’s common between DNA and RNA in terms of sugar?
They both have a sugar phosphate (pentose) backbone
What are both DNA and RNA made up of?
Nucleotides
Cytosine pairs with
Guanine
Adenine pairs with
Thymine
Guanine pairs with
Cytosine
Thymine pairs with
Adenine
How many hydrogen bonds link cytosine and guanine?
3
How many hydrogen bonds link adenine and thymine?
2
Which are stronger, hydrogen bonds between AT or between CG?
CG because there is one more hydrogen bond than in AT
Phosphodiester bond
Covalent bonds that pair nucleotides together
Central dogma for DNA
DNA -> RNA -> proteins
DNA codes for proteins