Ch. 2 Chemistry Macromolecules Flashcards
Organic Molecules
- Contain carbon and hydrogen
- Four Classes: Carbohydrates, lipids, proteins, nucleic acids
Stereoisomers
Same chemical formula, different spatial arrangement
a. Cis-trans isomers – geometric isomers
b. Enantiomers (optical isomers) = mirror images; rotate right (D) or left (L)
Functional Group
More reactive groups of atoms compared to the backbone of the hydrocarbon ring
- Usually contain atoms of oxygen, nitrogen, phosphorous, or sulfur
- Largely responsible for the unique chemical properties of the molecule
- Classes of organic molecules can be named according to their functional group
Hydrocarbon Ring/Chain
Relatively inactive molecular “backbone” to which more reactive groups are attached.
A bunch of C’s and H’s connected via single or double covalent bonds.
Organic Acids
- All contain a carboxyl group (COOH)
- It is an acid because it can donate its proton (H+) to the solution.
- Ionized organic acid is designated with the suffix “-ate”
Carbohydrates
- C:H:O in 1:2:1 ratio
- Major energy source
- Sugars and starches (“-ose”)
Monosaccharides
Glucose, fructose, galactose = C6H12O6
Polysaccharides
Many monosaccharides together
Dehydration Synthesis (Condensation)
How monosaccharides are bonded together covalently.
i.e.
Glucose + Glucose = Maltose + Water
Glucose + Fructose = Sucrose + Water
Hydrolysis
A digestion reaction, breaking covalent bonds in disaccharides and polysaccharides for use.
- Reverse of dehydration synthesis
- Breaking covalent bonds
Lipids
- Non-polar and hydrophobic
2. Functions: energy storage, cushioning, membrane function, hormone regulation
Lipid Classes
Triacylglycerols, phospholipids, steroids, prostaglandins
Triacylglycerols
- Fats (solids) and oils (liquids)
- Composed of 1 glycerol and 3 fatty acids
a) No double bonds = saturated
b) Double bonds = unsaturated - Aka neutral fats in adipose tissue
Ketone Bodies
Free fatty acids from adipose converted into ketone bodies by liver
Ketosis
Elevated ketone levels due to strict low- carbohydrate diets and uncontrolled diabetes
- If ketone levels high enough to lower blood pH = ketoacidosiscoma and death
Phospholipids
- Polar lipids containing a
phosphate group - Important in cell membrane bilayers
- Can form micelles in water
Steroids
3 six-carbon rings + 1 five- carbon ring + different functional groups
Cholesterol (as an ex. of a steroid)
a) precursor to steroid hormones produced by gonads and adrenal cortex
b) Important part of cell membrane
c) Precursor to bile salts and vitamin D3
Prostaglandins
- Type of fatty acid with a cyclic hydrocarbon group
- Serve as communication molecules between cells in the same organ
- Help regulate blood vessel diameter,
ovulation, uterine contractions, inflammatory reactions, blood clotting, etc.
Protein Functions
Structural, enzymes, antibodies, receptors, carriers
Structural (Proteins)
Collagen fibers in connective tissues; keratin in skin
Enzyme (Proteins)
Assist every chemical process in the body
Antibodies (Proteins)
Part of the immune system
Receptors (Proteins)
Receive communication from other
cells for regulation of cell activity
Carriers (Proteins)
Across cell membranes or in blood
Proteins
Long chains of subunits called amino acids, bonded together through covalent and peptide bonds.
Amino Acids
- Consists of an amino group (NH2) and a carboxyl group (COOH)
- 20 different amino acids, each with distinct structures and chemical properties used to build proteins
Functional Groups (Amino Acids)
The differences between amino acids
Peptide Bonds
The bonds between two adjacent amino acids, forming peptides.
Polypeptide
Numerous amino acids bonded together
Tripeptide
Three amino acids bonded together
Dipeptide
Two amino acids bonded together
Primary Protein Structure
The sequence of amino acids in a particular protein
- Aka polypeptide strands.
- The sequence comes from ones genes
Secondary Protein Structure
(Basically, the double Helix)
The shape of polypeptide bonds due to weak hydrogen bonds.
Two Shapes: alpha helix; beta pleated sheet
Tertiary Protein Structure
The three-dimensional shape of a polypeptide chain after it has folded up on itself.
Formed and stabilized by weak chemical interaction between the functional group
Quaternary Protein Structure
Several polypeptide chains covalently bonded together.
Denaturation of Proteins
Changes in the tertiary structure of proteins. Retain primary structure, but have altered chemical properties.
Nucleic Acids
Macromolecules include DNA and RNA.
Nucleotides
Subunits of nucleic acids.
Composed of a five-cabron (pentose) sugar with a phosphate group on one side and a nitrogenous base on the other.
Polynucleotide Chain
Nucleotides bonded together in dehydration synthesis.
Nitrogenous Base
Nitrogen-containing molecules of two kinds: pyrimidines and purines
DNA (Deoxyribonucleic Acid)
Basis for genetic code. Extremely long, but relatively simple compared to other molecules and proteins.
Purines (Nitrogenous Base)
Double ring of carbon and nitrogen. Bases include guanine and adenine.
Pyrimidines (Nitrogenous Base)
Single ring of carbon and nitrogen. Bases include cytosine and thymine
DNA Nucleotides
Purines: guanine and adenine
Pyrimidines: cytosine and thymine
Law of Complementary Base Pairing
Adenine can pair only with thymine (through TWO hydrogen bonds), whereas guanine can pair only with cytosine (through THREE hydrogen bonds).
RNA (Ribonucleic Acid)
Long chains of nucleotides, joined together by sugar-phosphate bonds.
DNA and RNA differences
- ) RNA contains the sugar ribose instead of deoxyribose
- ) RNA contains uracil instead of thymine
- ) RNA is single stranded instead of double
Three types of RNA
mRNA, tRNA, rRNA. They are all made within the cell nucleus using DNA information.
Other important RNA-related molecules
ATP, GTP, cAMP, NAD & FAD
Monomers of Proteins
Amino acids (20 different ones)
Monomers of Carbohydrates
Monosaccharides (Saccharine = sugar, mono = one…. One Sugar)
i.e. - Glucose, fructose, galactose
Monomers of Nucleic Acids
Nucleotides
Contains: Phosphate group, pentose (Ribose and deoxyribos), addenine, guanine, thymine, cyosine, uracil
Monomers of Lipids
They have monomers, but there are a ton. Typically what you talk about are triglycerides
