Molecules and Fundamentals of Biology Flashcards
Chapter one
What are Ribose, Fructose and Glucose?
Monosaccharides
Ribose has how many carbons?
Five Carbons
Fructose has how many carbons?
Six Carbons
Glucose has how many carbons?
Six Carbons
What is a hydrolysis reaction?
Bond Broken by addition of water
What is Sucrose?
Glucose + Fructose disaccharide
What is Lactose?
Galactose + Glucose disaccharide
What is Maltose?
Glucose + Glucose disaccharide
What is Starch?
Energy storage for plants (alpha bonded)
What are the two types of starch?
Linear and Branched
What does linear starch consist of?
Amylose
What does branched starch consist of?
Amylopectin
What is glycogen?
Energy storage for humans (alpha bonded), more branched than starch
What is cellulose?
Structural component in plant cell walls (beta bonded)
What is Chitin?
Structural component in fungi cell walls and insect exoskeleton (beta bonded +nitrogen)
What do proteins contain?
Carbon, hydrogen, oxygen and nitrogen. Which are amino acids -> polypeptides/proteins are joining by peptide bonds.
What are amino acids?
Monomers of proteins
How many amino acids are there?
20
What are the two end terminals of each amino acid chain?
N-Terminus and C-Terminus
What does N-Terminus end with?
An Amino Acid
What does C-terminus end with?
Ends with the last amino acids carboxyl group
Describe the Primary structure of a protein structure
Sequence of amino acids
Describe the Secondary structure of a protein structure
Intermolecular forces between polypeptide backbone due to hydrogen bonding, forms a-helices and b-pleated
Describe the Tertiary structure of a protein structure
3-D structure, create hydrophobic and hydrophilic , sulfide bonds
Describe Quaternary structure of a protein structure
Multiple polypeptide chains come together to form one protein
Classifications of proteins
Fibrous, globular and intermediate.
Can be simple (amino acids only)
Conjugated (amino acids plus other components)
What is protein denaturation?
Loss of protein function and higher order structures. Only the primary structure is unaffected so the sequence of amino acids.
What are reasons for protein denaturation?
High/low temps, pH changes, salt concentrations
Function of Storage in proteins
Reserve of amino acids
Function of Hormones in proteins
Signaling molecules that circulate through the body to regulate physiological processes
Function of Receptors in proteins
Protein in cell membranes, bind to signal molecules to trigger charges
Function of Motion in proteins
Movement generation for cell or whole organisms
Function of Structure in proteins
Provide strength and support to tissues
Function of Immunity in proteins
Prevention and protection against foreign invaders
Function of Enzymes in proteins
Biological catalysts binding to substrates converting to products. Most enzymes are proteins.
What are catalysts?
Increase reaction rates by lowering activation energy and reduce transition state. Do not shift chemical reaction or affect spontaneity.
What is a transition state?
The unstable intermediate between reactants and products.
Define specificity constant
Measures how efficient an enzyme is at binding to the substrate and converting to product
What is the induced fit theory?
Active site molds itself and changes shape to fit the substrate when it binds
What is ribozyme?
Is an RNA molecule that can act as enzyme (nonprotein)
What is a cofactor?
Is a nonprotein molecule that helps enzymes perform reactions
What two types of cofactors are there?
Organic (vitamins)
Inorganic (Metal ions)
What are Moloenzymes?
Enzymes bound to cofactors (tightly bound, prosthetic groups)
What are apoenzymes?
Enzymes not bound to their cofactors
What is competitive inhibition?
When a competitive inhibitor directly competes with the substrate for active binding site
How can we increase enzyme action?
By adding more substrate
What is noncompetitive inhibition?
The noncompetitive inhibitor binds to an allosteric site, modifying the active site. The allosteric site is different than the active site. Enzyme action cannot be increased.
How does the competitive inhibition look on the enzyme kinetics plot?
Km increases while Vmax stays the same
How does the noncompetitive inhibition look on the enzyme kinetics plot?
Km stays the same while Vmax decreases
What are lipids?
Contain carbon, hydrogen, and oxygen. (Carbohydrates) Have long hydrocarbon tails = hydrophobic.
What do Triglycerol - lipids consist of?
With glycerol backbone. Glycerol + three fatty acids connected by ester linkages.
What makes a chain saturated?
Has no double bonds, tightly packed (solid at room temp)
What makes a chain unsaturated?
Have double bonds
What do Cis-unsaturated fatty acids have?
Have kinks that cause the hydrocarbon tails to bend they do no pack tightly
What do Trans-unsaturated fatty acids have?
Have straighter hydrocarbon tails that pack tightly together
What do phospholipids consist of?
glycerol backbone, one phosphate group (polar), two fatty acids (nonpolar) which cause to be amphipathic
What does amphipathic mean?
Hydrophilic and hydrophobic
What is cholesterol?
Lipid molecule, amphipathic, most common precursor of steroid hormone, vitamin D and bile acids
How does temperature affect membrane fluidity?
High-temperature increases fluidity, low-temperature decrease fluidity.
How does cholesterol affect membrane fluidity?
Cholesterol holds the membrane together at high temperature and keeps membrane fluid down at low temperatures.
Describe saturated fatty acids
Pack more tightly
Describe unsaturated fatty acids
Less packed, have double bonds and introduce kinks
What do Lipoproteins do?
Allow the transport of lipid molecules in the bloodstream due to an outer coat of phospholipids, cholesterol, and proteins.
What are low-density lipoproteins?
Bad cholesterol and vessel blockage can occur leading to heart disease. Will deliver to peripheral tissue.
What are high-density lipoproteins?
High protein density takes cholesterol away from peripheral tissues, good cholesterol is sent to the liver to make bile.
What are waxes?
Simple lipids that have long fatty acids connected to mono hydroxyl alcohols. Used mainly as a hydrophobic protective coating.
What are carotenoids?
Function as pigments. Long-chain conjugated with double bonds and six-membered rings at each end.
What are the nucleic acids?
Contain nitrogen, oxygen, phosphorus, hydrogen, carbon. Contain nucleotide that builds into DNA and RNA.
What are nucleosides?
Five carbon sugar and a nitrogenous base
What do nucleotides contain?
Contain a phosphate group plus five-carbon sugar and a nitrogenous base.
What does deoxyribose contain?
In DNA contain hydrogen at 2 carbon
Where are ribose located?
In hydroxyl group at 2’carbon
Nucleotides in DNA and RNA
Adenine, Thymine, Cytosine, Guanine. Uracil replaces thymine in RNA.
What are Purines?
Two rings; Pur As Gold = Purines are Adenine and Guanine
What are Pyrimidines?
One ring; CUT the Py = Cytosine, Uracil and thymine are pyrmindines.
Phosphodiester bonds do what?
Connect phosphate group of one nucleotide at 5’carbon to hydroxyl group of another nucleotide at 3’
DNA strands and transcription
Antiparallel double helix, two complementary strands with opposite directionalities.
A-T
G-C
RNA strand and transcription
Single-stranded.
A-U
G-C
How is genetic information passed down?
Through DNA
What is Modern Cell theory?
All life forms have one or more cells.
All cells come from other cells
metabolism and biochemistry occurs within cells
all cells have the same chemical composition within similar species
organism activity is dependent on total activity.
What is the central dogma of genetics?
Information passed from DNA to RNA to proteins
What is RNA world hypothesis?
RNA dominated Earth.
RNA developed self-replicating and could later catalyze reactions such as protein synthesis.
RNA is reactive and unstable, DNA became a better way
