Macromolecules and enzymes Flashcards
What is a macromolecule and what are they?
Complex, large, organic molecules:
-Carboydrates (sugars)
-Lipids (fats and oils)
-Proteins
-Nucleic acids (RNA and DNA)
What is the difference between monomer and polymer?
-Monomer: macromolecule made of one unit
-Polymer: macromolecule made of many monomer subunits
What are the monosaccharides of carbohydrates?
Glucose, fructose, galactose, deoxyribose and ribose
What are the disaccharides of carbohydrates?
-Lactose (glucose + galactose)
-Sucrose (glucose + fructose)
-Maltose (2 glucoses)
What are the polysaccharides of carbohydrates?
Starch, cellulose, and glycogen
Define starch
Polymer of glucose, used by plants to store energy, digestible
Define cellulose
Polymer of glucose, component of plant’s cell wall, indigestible
Define glycogen
Polymer of glucose, stored in animal tissues (muscles and liver)
What are the functions of carbohydrates?
-Glucose is the favorite fuel for cells (ATP is produced during glucose breakdown process)
-Combine with other macromolecules to form cell structures (glycoproteins and glycolipids)
What are lipids and its major groups?
-Hydrophobic (don’t mix with water)
-3 groups: triglycerides, phospholipids, and steroids (sterol)
What are triglycerides?
-Abundant in body tissues (as fat)
-Structure: glycerol backbone + 3 fatty acids
Structure of diglyceride?
Glycerol + 2 fatty acids
Structure of monoglyceride?
Glycerol + 1 fatty acid
How can triglycerides vary?
Fatty acids vary:
-Length (n.b of carbon atoms)
-Degree of saturation (presence/absence of carbon double bonds)
What are saturated fats?
No double carbon bond, animal source, solid or semi-solid at RT (ex: butter)
What are unsaturated fats?
Double carbon bonds, plant source, liquid at RT (ex: olive oil)
What are the functions of triglycerides)
-Important fuel source for the body
-Help with the absorption of fat-soluble vitamins
-Insulation and protection
What are phospholipids?
-Modified triglycerides:
Glycerol backbone + 2 fatty acids and phosphate group
Hydrophilic head and hydrophobic tail
-Major structural components of the cell membrane
What are steroids?
-Structure: 4 hydrocarbon rings joined together + side chain
-Synthesized by both plants and animals
-Cholesterol is very important for humans (bile acids, hormones, vitamins)
What are proteins?
Their building blocks are amino acids linked by peptide bonds
What are the 3 parts of amino acids?
-Carboxyl group (-COOH)
-Amino group (-NH3)
-Variable side chain (R-group) makes 20 unique amino acids
What are the structure/names of proteins?
The carboxyl and amino groups bond together to form peptide bond
-Dipeptide (2 amino acids)
-Tripeptide (3 amino acids)
-Polypeptide (fewer than 100 amino acids)
-Protein (more than 100 amino acids)
What are the protein structural levels?
-Primary structure
-Secondary structure
-Tertiary structure
-Quaternary structure
Define primary structure
Sequence/order of amino acids
Define secondary structure
Alpha helices and pleated sheets
Define tertiary structure
Folding alpha helices and pleated sheets (3D) (functional protein)
Define quaternary structure
Assembly of many folded polypeptides (many subunits)
What are the functions of proteins?
-Structural (Keratin in nails and hair)
-Movement (Actin and myosin in muscle cells)
-Defense (Antibodies of the immune system are proteins)
-Storage (Albumin in egg white provides nutrients for the embryo)
-Signaling (Growth hormone is a hormonal messenger)
-Catalyzing reactions (Amylase is an enzyme that breaks down starch)
What are enzymes?
Proteins with a very specific function:
-Catalysts increase rate of reactions
-Enzymes are biological catalysts
-Lower required activation energy
What are catalyzed reactions?
-Anabolic rx = Synthesis (energy stored) (2 substrates = 1 product)
-Catabolic rx = Breakdown (energy released) (1 substrate = 2 products)
