C2: Biological Molecules Part II Flashcards
Differentiate inorganic and organic compounds.
Inorganic compounds may or may not contain carbon (EX: salt). Organic compounds must contain carbon (EX: hydrocarbons).
What are the prefixes for naming hydrocarbons based on the number of carbons in the carbon chain (backbone)?
1 - Meth
2 - Eth
3 - Pro
4 - But
5 - Pent
6 - Hex
What are the suffixes for naming the hydrocarbons based on the carbon-carbon bond type?
Single bond - ane
Double bond - ene
Triple bond - yne
What are structural isomers?
molecules with the same molecular formula but differ in arrangement of atoms
What are geometrical isomers?
molecules with same molecular formula but differ in spatial arrangement
What are optical isomers?
molecules with same molecular formula but are mirror images of each other
What functional group contains —OH?
Hydroxyl group
What functional group contains C=O?
Carbonyl group
What functional group contains —COOH?
Carboxyl group
What functional group contains —NH₂
Amino group
What functional group contains —OPO₃²⁻?
Phosphate group
What functional group contains —CH₃?
Methyl group
What structures can pentoses and hexoses make due to their long carbon chain?
ring structures
What is the reaction that makes polymers?
Polymerization
What is the process of adding water to break monomers called? (Two ways)
Hydrolysis or Digestion
What is the process of removing water to connect two monomers called? (Three ways)
Dehydration synthesis, Condensation reaction, or Polymerization
What is the function of carbohydrates?
They are the primary source of energy and give structural support to cells.
What is the ratio that is important in identifying carbohydrates?
The ratio of hydrogen to oxygen atoms is 2 : 1
What suffix do monosaccharides’ names end with?
-ose
What are the two functions of monosaccharides?
- Energy source for respiration (due to C-H bonds)
- Building block for larger molecules
Name some properties of glucose.
Glucose is water soluble and very reactive.
Differentiate α and β glucose.
α-glucose has an hydroxyl group facing down while β-glucose has an hydroxyl group facing up.
What bond is needed to form a disaccharide?
glycosidic bond
What reagent is needed to test for reducing sugars?
Benedict’s solution (makes redox reaction occur when heated)
What color change indicates the presence of reducing sugars?
blue -> red
What substance is needed to perform hydrolysis and test for non-reducing sugars?
Hydrochloric acid (HCL)
What substance is needed to neutralize the excess acids in monosaccharides?
sodium hydrogen carbonate
What monosaccharides make up sucrose?
Glucose and Fructose
What monosaccharides make up lactose?
Galactose and Glucose
What monosaccharides make up maltose?
Glucose and Glucose
What linkage does maltose have?
1-4 glycosidic bond
What linkage does sucrose have?
1-2 glycosidic bond
What are polysaccharides?
polymers made up of many monosaccharides (via condensation reaction)
What is starch made up of?
Amylose and Amylopectin
What are some properties of amylose?
- α-glucose as its subunit
- only 1-4 glycosidic linkage
- glucose are oriented in the same direction forming chains and helical structures (compact)
What are some properties of amylopectin?
- α-glucose as subunit
- 1-4 and 1-6 glycosidic linkages
- branched structure due to 1-6 linkages (~per 20 subunits)
Where are large starch grains commonly found?
in chloroplasts and storage organs
What are some properties of glycogen?
- α-glucose as subunit
- 1-4 and 1-6 glycosidic linkages
- branched structure due to 1-6 linkages (~per 10 subunits)
What do glycogen molecules form when clumped together?
They form granules that can be stored in the liver and muscle cells to serve as an energy reserve.
What are some properties of cellulose?
- β-glucose as subunit
- only 1-4 glycosidic linkages
- high tensile strength
- has a slow rate of breakdown
- glucose molecules are oriented alternately up and down to make a straight chain
Why is cellulose so strong?
due to the many hydrogen bonds (abundant —OH groups)
What is the difference between aldehydes and ketones
Aldehydes have a carbonyl group at the end of a carbon chain while ketones have a carbonyl group within the carbon chain.
Describe the assembly of cellulose molecules.
First, once 60 to 70 cellulose molecules are bonded, they form bundles called microfibrils. The microfibrils then gather to form bundles called fibers.
Describe the permeability of cellulose fibers (made up of microfibrils).
They are freely permeable.
Where does iodine fit into in starch molecules?
Starch molecules curl up into long spirals, and the hollow area that runs down the middle of the spiral is the place where iodine fits in.
What color change indicates the presence of polysaccharides?
orange-brown -> blue-black
What is created when electron sharing is unequal?
a dipole
How do the properties of dipoles and non-dipoles relate to their interactions with water and other polar solvents?
Dipoles are hydrophilic and non-dipoles are hydrophobic.
What are lipids?
organic molecules that are insoluble in water
Differentiate fats and oils.
Fats are lipids that are solid at room temperature and oils are lipids that are liquid at room temperature.
What are the two monomers of lipids?
fatty acids and alcohol
What are some properties of fatty acids?
They have long hydrocarbon chains that are attached to a carboxyl group.
What are some properties of alcohols?
They contain a hydroxyl group that is attached to a carbon atom.
How and where do ester bonds form?
Ester bonds form between an acid and an alcohol through a condensation reaction.
Differentiate saturated and unsaturated fatty acids.
Saturated fatty acids have a straight, unbranched chain that contains the maximum possible amount of hydrogen while unsaturated fatty acids do not contain the maximum possible amount of hydrogen due to the double bonds between carbon atoms (produces kinks in the structure as well)
Differentiate monounsaturated and polyunsaturated fatty acids.
Monounsaturated fatty acids only contain one double bond (C=C) in their hydrocarbon chain while polyunsaturated fatty acids contain multiple double bonds in their hydrocarbon chain.
What makes unsaturated lipids melt easily?
the double bonds
Plant lipids are usually ______ and animal lipids are usually ______.
unsaturated, saturated
What are triglycerides?
a lipid made up of three fatty acid molecules and one glycerol molecule
Explain lipids’ three primary functions.
- storing long-term energy
- insulation
- metabolic source of water
What are phospholipids?
a type of amphipathic lipid
What allows phospholipids to be soluble in water?
the phosphate group (both polar and hydrophilic)
What test is needed to test for lipids?
the emulsion test
What two reagents are needed when testing for lipids?
ethanol and water (tests for solubility after breaking down lipid)
What three reagents are needed when testing for disaccharides?
Benedict’s solution, hydrochloric acid (HCL), and sodium hydroxide
What color change indicates the presence of disaccharides?
blue -> red
What reagent is needed when testing for polysaccharides?
Iodine (complex forms between iodine and polysaccharide)
What result indicates the presence of lipids?
cloudy white suspensions (foamy bubbles)
Where are phospholipids primarily found?
in cell membranes
What are the eight functions of proteins?
- Structural support to cell membrane
- Transport molecules
- Immunity
- Make up most enzymes
- Support cells and tissues
- Make up some hormones
- Muscle contraction
- Storage
What are the monomers of proteins?
amino acids
What do all amino acids have in common (molecular structure)?
an amino group, a carboxylic acid group, an α-carbon, and a hydrogen atom
How many different amino acids are there?
20
What are the four classes of amino acids?
non-polar, polar, positively charged (basic), and negatively charged (acidic)
What is a peptide bond?
a bond formed between amine group and carboxylic acid group when two or more amino acids join together
Where are proteins made?
ribosomes
Where do polypeptides primarily go through hydrolysis?
the stomach and small intestine
Explain the primary, secondary, tertiary, and quaternary structures of proteins.
Primary - the sequence of amino acids
Secondary - when amino acids form hydrogen bonds and create α-helixes and β-pleated sheets by coiling and folding
Tertiary - precise 3D shape of protein due to hydrogen, disulfide, and ionic bonds (also hydrophobic interactions)
Quaternary - different polypeptides bond together and associate with each other
What are globular proteins?
a protein that has a spherical shape; hydrophobic amino acids point to the center of the molecule while hydrophilic amino acids point outwards (globular proteins are soluble due to this)
What are fibrous proteins?
proteins that form long strands instead of curling up (fibrous proteins are insoluble and have structural roles)
What is hemoglobin?
an oxygen-carrying globular protein within red blood cells
What is hemoglobin made up of?
4 polypeptide chains (2 α-chains and 2 β-chains)
What is the heme group?
a type of prosthetic group that contains Fe²⁻ which can bond to an O₂ molecule (gives hemoglobin reddish color and does not contain amino acids)
What is collagen?
a fibrous protein that provides structural support to tissues and organs
What makes up collagen, and how are they held together?
3 polypeptide chains in the shape of a helix; the 3 strands are held together by hydrogen bonds (glycine is found every third amino acid)
How are collagen fibers held together?
through bonds that form between the R groups of glycine in adjacent molecules
What reagent is needed when testing for proteins?
Biuret solution (detects peptide bonds)
What color change indicates the presence of proteins?
blue -> purple
What causes proteins to denature?
high temperatures and pH changes
