Biological Molecules Flashcards
Chapter 2, Pt 2
What areBiological Molecules (Biomolecule)?
Any of the numerous substances that are produced by living things
Carbohydrates, Lipids, Proteins, Nucleic Acid
What are Proteins?
One of the most abundant organic molecules in living systems and have the most diverse range of functions
What are the 8 functions of Proteins?
Catalysis:
Defense:
Transport:
Support:
Motion:
Regulation:
Storage:
Toxin:
What is the structre and compostion of proteins?
-Proteins contain carbon, hydrogen, and nitrogen as major compounds
-All proteins are polymers of amino acids
-Contain an amino group(-NH₂) and a carboxyl group (-COOH)
Know how to draw basic structure of a protein
How are protein classififed?
Proteins can be classified by:
Size
Nature
Molecular Shape
Conformation
What are Fibrous Proteins?
-Functional in the second level of confirmation
-insoluble in water, physically tough
-Composed of long polypeptide chains crosslinked at the internal forming a long fibrous sheet
-Have structural functions e.g. collagen, myosin, silk, keratin
What are Globular Proteins?
-Tightly folded proteins that form spherical shapes that are easily soluble
-Mostly exist in the tertiary level of conformation
enzymes, antibodies, hormones
What areIntermediate Proteins
Fibrous but soluble proteins
e.g. fibrinogen (forms an insoluble fibrin when blood cloths
What is the primary structure of a protein?
The unique sequence and number of amino acids in a polypeptide chain
-Higher levels of organization are decoded by the primary structure
What is the secondary structure of a protein?
-A regular recurring arrangement in the space of adjacent amino acid residues in a polypeptide chain
-Maintained by hydrogen bonds betweenamide hydrogens and carboxy oxygen of the peptide back bone
What is a Alpha Helix Secondary Structre
A structre in which hydrogen bonds form between amide hydrogens and carboxyl oxygen of the peptide backbone (four amino acids apart) causing a twist in the amino acid chain
What is a Beta () Pleated Sheet Secondary Structre
-Formed by hydrogen bonding between atoms on the backbone of the polypeptide chain
What is a Carbohydrate?
Are organic compounds with the general formula(CH₂O)n where n = 3
to 9
-The most abundant and widespread organic substances in nature and essential constituents of all living things
What are monoscaccerides?
Simple sugars that are the monomersof carbohydrates
-Glucose (C₆H₁₂O₆): A primary energy source for cells
-Fructose (C₆H₁₂O₆): Found in fruits
-Galactose (C₆H₁₂O₆): Found in milk sugar
What are Disaccharide (Double Sugar)?
Two monosacceide molecules of a simple sugar that are linked to each other by Glycosidic bonds
General Formula: C₁₂H₂₂O₁₁
-Sucrose: (Glucose + Fructose)
-Lactose: (Glucose + Galactose)
-Maltose: (Glucose + Glucose)
What are Oligosaccharides?
Carbohydrates that consist of three to six monosaccharides
What are Polysaccharides
Large molecules that can consist of as many as 10,00 monosaccharides
General Formula: Cₓ(H₂O)ᵧ
What is Cellulose?
The principal structural component of plants, a complex polysaccharide consisting of many glucose units linked together
-Found in plant cell walls
What is Starch?
Complex glucose polysaccharide
-Storage form of glucose in plants
What is Glycogen?
Complex glucose polysaccharide
-Storage form of glucose in humans and other vertebrae
-Stored in liver and muscle cells
Aldehyde Group
Ketone Group
Carbohydrate: Cellulase
Breaks down cellulose into glucose
Lipids
Hydrophobic (“water-fearing”), nonpolar molecules that serve several important biological functions and include various
-Store energy for long-term use in the form in adipocytes
Function of Lipids
-Storage form of energy
-Structural component of bio-membranes
-Provide insulation against external temp (subcutaneous fat)
-Protects internal organs providing a cushioning effect (pads & fat)
-Metabolic regulations (steroid, hormones, prostaglandins)
-Acts as electric insulators in neurons
-Help in the absorption of fat-soluble vitamins (A,D,E,and K)
Classification of Lipids
Can be classified as simple or compound
-Simple: Esters of fatty acids with glycerol or other higher alcohols
-Compound: Fatty acids esters with alcohols but in addition they contain other groups
Ex: Phospholipids, Derived Lipids, Glucolipids
Phospholipids
Lipids containing phosphate groups
-Forms when one of the three -Oh groups of glycerol combine with phosphoric acid instead of a fatty acid
-Phosphate head us hydrophilic and the other end is hydrophobic
Glycolipids
Lipids with a carbohydrate attached by a glycosidic (covalent) bond.
Steroids.
Triglyceride
It consists of two main components- glycerol and fatty acid
-A fatty acid is attached to each of the three oxygen atoms in the -OH groups of the glycerol molecule with a covalent bond
Gylcerol
An organic compound with three carbon atoms, five hydrogen atoms, and, and three hydroxyl groups(-OH)
Fatty Acid
Long chain of hydrocarbons to which an acidic carboxyl group (-COOH) is attached
Unsaturated Fats (Oils)
-Contains one or more double bonds in its hydrocarbon chain (not saturated in hydrogen atoms)
-Liquid at room temp
One double bond gives a monounsaturated fat (olive oil)
-More than one double bond gives polyunsaturated fat (canola oil)
-Improves blood cholesterol Lvl
Saturated Fat
It doesn’t contain double bonds in the hydrocarbon chain (saturated in hydrogen atoms)
-Solid at room temperature
-Stored in adipocytes in humans, stored in seeds in plants
-Forms plaque in arterial wall
Nucleic Acids
Key macromolecules carry the genetic blueprint of a cell and carry instructions for cell function
Nucleotide
The precursors of the nucleic acids
-made up of
-A Nitrogenous base (Purine or pyrimidine)
-Pentose sugar (Ribose or Deoxyribose)
-Phosphate Group
Formation of a Nucleic Acid
Formation of a Nucleotide
Purines:
Pyrimidines:
DNA (Deoxyribonucleic acid)
RNA (Ribonucleic Acid)
DNA Double-Helical Structure
Other Common Nucleotides
