Biology: Molecules and Fundamentals Flashcards
What is matter
Anything that takes up space and has mass
What is an element?
A pure substance that has a specific physical/chemical properties that cannot be broken down into simpler substance
What is an atom?
Smallest unit of matter that retain chemical properties of elements
What is a molecule?
Two or more atoms joined together
What are intramolecular forces?
Attractive forces that act on atoms within a molecule
What are intermolecular forces?
Forces that exist between molecules and affect physical properties of the substance
What is the difference between intermolecular and intramolecular forces?
Intramolecular forces are the forces WITHIN a molecule and intermolecular forces are the forces BETWEEN two molecules
What are monomers?
Single molecules that can potentially polymerize
What are polymers?
Substances made of many monomers joined together
Monosaccharides
carbohydrates monomers
What are ribose?
5 carbon monosaccharide
What is fructose?
6 carbon monosaccharide that is an isomer of glucose
What is glucose?
6 carbon monosaccharide that is an isomer of fructose
What is a disaccharide
two monosaccharide joined together by glycosidic bond
What is the difference between dehydration reaction and hydrolysis’ reaction?
Dehydration reaction is where a water molecule leaves, forming a covalent bond between two monosaccharide. A hydrolysis reaction is where a water molecule is used to break a chain
What is sucrose?
glucose + fructose
What is lactose
galactose + glucose
What is maltose
glucose + glucose
What is starch?
Form of energy storage for plants. Alpha bonded polysaccahride
What is the difference between amylose and amylopectin?
Amylose is the linear form of polymer while amylopectin is the branched form
What is the difference between starch and glycogen?
Glycogen has more branching than starch. They’re both alpha bonded polysaccharide
What is cellulose?
A structural component in plant cell that is beta bonded polysaccharide
Chitin
structural component in fungal cell wall and insect exoskeleton that is beta bonded polysaccharide with nitrogen added to each monomer
What are amino acids
monomers of protein
What are polypeptides
Polymers of amino acids that are linked by peptide bonds through dehydration reaction
What are conjugated proteins?
protein that are composed of amino acids and non protein components
What are primary structure?
sequence of amino acids connected by peptide bonds
What are secondary structure?
Intermolecular forces between the polypeptide backbone due to hydrogen bonding. This forms alpha helices and beta pleated sheets
What are tertiary structure?
3-D structure due to interaction between R groups.
Quaternary structure
Multiple polypeptide chains coming together to form one protein
What is protein denaturation?
Loss of protein function as a result of high or low temperature, pH changes, and salt concentration
What does catalyst do to reaction
Increase reaction rates by lowering the activation energy of a reaction
What are enzymes?
Biological catalyst that binds to substrate (reactants) and converting them to product
What are ribozyme?
RNA molecular that can act as an enzyme
What are cofactor?
non-protein molecule that helps an enzyme perform reaction
Holoenzyme vs apoenzyme
Holoenzymes that are bound to their cofactors while apoenzyme are not
Prosthetic group
cofactor that are tightly bound to their enzyme
How does enzyme catalyze reaction?
- Conformation changes, bringing reactive group closer
- Presence of acidic or basic group
- Induced fit of the enzyme substrate
- Electrostatic attraction between enzyme and substrate
What can enzymes do?
- Phosphatase: cleave phosphate group off a substrate
- Phosphorylate: Directly add a phosphate group to substrate by breaking bonds within a substrate molecule
- Kinase: indirectly adds a phosphate group to a substrate by transferring a phosphate group from an ATP molecule. These enzymes do not break bonds to add phosphate group
How feedback regulation of enzymes work
The end product of an enzyme catalyzed reaction inhibits the enzyme activity by binding to an allosteric site of enzymes
Competitive vs Noncompetitive inhibition
Competitive inhibitor competes directly with the substrate for active site binding. Therefore, adding more substrate increase enzyme action.
Non competitive inhibition occurs when the inhibitor binds to an allosteric site, modifying the active site so substrate cannot bind to enzyme. Therefore, the rate of enzymes action cannot be increased if more substrates are added
What is a triacyglycerol?
Glycerol backbone and 3 fatty acids
Saturated fatty acid
No double bonds and pack tightly at room temperature
Unsaturated fatty acid
Double bonds in fatty acid chain
What are phospholipids
Lipid molecules that have a glycerol backbone, one phosphate group, and two fatty acid tail
What is cholesterol?
amphipathic lipid molecule that is a component of cell membrane
Factors that influence membrane fluidity
- Temperature (positive correlation)
- Cholesterol (hold membrane together at high and keep membrane fluid at low)
- Degree of unsaturation (more saturation, less fuidity)
Waxes
lipid with long fatty acid chain connected to monohydroxy alcohol through ester linkage
Carotenoids
lipid derivative with conjugated double bonds and six membered rings at each end
Sphingolipid
Aliphatic amino alcohol
Glycolipid
lipid found in cell membrane with a carbohydrate group attached instead of a phosphate group
