CHP 3 BIOL 2311 Flashcards
(73 cards)
What are the 6 most common elements in biological molecules?
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, Sulfur
Define a molecule
A chemical substance that results from the combination of two or more atoms
Define a compound
Molecules that are combinations of two or more different elements
What are the three types of chemical bonds? Describe them
Covalent bonds: non-polar equal sharing of electrons, polar unequal sharing of electrons
Ionic Bonds: electrons that are transferred to one atom forming positively charged cations and negatively charged anions.
Hydrogen Bonds: Electrostatic attraction between Hydrogen and Nitrogen or Oxygen.
What is a solution? Describe it.
A mixture of one or more substances called solutes, dispersed in a dissolving medium called a solvent.
Describe the three types of molecules found within aqueous solutions and their relationship to water
Hydrophilic molecules, dissolve in water.
Hydrophobic molecules, repel water.
Amphipathic molecules, have both hydrophilic and hydrophobic properties
Why is water so special within biology?
Liquid at most earth temperatures, it resists temperature changes, it is a superb solvent, it has high cohesion, adhesion and tension due to hydrogen bonds, acts as a buffer.
What do organic and inorganic compounds contain?
Organic compounds contain carbon bonded to hydrogen
Inorganic compounds lack carbon and hydrogen such as CO2.
What is pH?
It ranges from 0-14 and expresses the concentration of H+ ions.
What are the four major classes of organic molecules within a living organism?
Carbohydrate, lipids, proteins, and nucleic acids.
What is a hydrocarbon?
Molecules consisting of carbon linked only to hydrogen atoms.
How many unpaired outer electrons does carbon contain?
4
What is the simplest hydrocarbon?
CH4 (Methane) it consists of a single carbon atom bonded to four hydrogen atoms.
What is Chemical Evolution?
It resulted in the first forms of life on Earth after formation of organic molecules.
What are functional groups and which one most frequently enter into most biological reactions?
Functional groups are small reactive groups of atoms which give larger molecules specific chemical properties.
Functional groups that enter most frequently into biological reactions are the hydroxyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl groups.
What are isomers?
Molecules that have the same chemical formula but different molecular structures.
What are stereoisomers?
Isomers that are mirror images of each other such as glyceraldehyde
What are structural isomers?
Two molecules with the same chemical formula but atoms are arranged in different ways. EX: glucose, an aldehyde and fructose, a ketone.
What is a dehydration synthesis reaction?
When water components are removed from a group. New covalent bonds join subunits into a larger molecule.
What is hydrolysis?
When water components are added. Covalent bonds are broken, splitting a molecule into smaller subunits.
The 4 Biological Macromolecules
Carbohydrates, Lipids, Proteins, Nucleic Acid
What are Monomers
A repeating subunit
What are polymers
Chain of monomers
What are large polymers, what are they assembled from and connected by what chain?
Large polymers are carbohydrates, lipids, proteins, and nucleic acid, assembled from subunit molecules (monomers), connected by a chain of covalent bond.