The random motion of molecules from an area of high concentration to an area of low concentration.
A membrane that allows some molecules to pass through but does not allow other molecules to pass through.
The tendency of a solvent to travel across a semipermeable membrane into areas of higher solute concentrate.
A substance that alters the speed of a chemical reaction but is not used up in the process.
A molecule that contains only carbon and any of the following: hydrogen, oxygen, nitrogen, sulfur, and/or phosphorous.
A lipid made from fatty acids that have at least one double bond between carbon atoms.
A strong attraction between hydrogen atoms and certain other atoms (usually oxygen or nitrogen) in specific.
Describe where the protons, neutrons, and electrons are in an atom.
Protons and neutrons make up the nucleus of the atom (the center), and the electrons circle around the neutrons and protons.
What determines the vast majority of characteristics in an atom?
The vast majority of an atom's properties are determined by the number of electrons (or protons) that an atom has.
What is the difference between an element and an atom?
An element is a collection of atoms that all have the same number of protons, an atom is a fundamental piece of matter. (Matter is anything that takes up space)
How many atoms (total) are in a molecule of C3H8O? What atoms are present and how many of each atom?
12 atoms total, 3 Carbon, 8 Hydrogen, 1 Oxygen.
Identify the following as an atom, element, or molecule:
a. H2CO3 b. nitrogen-14 c. P
a. Element b. Atom c. Element.
Two solutions of different solute concentration are separated by a membrane. After a while, the water levels of the two solutions change. Has osmosis or diffusion taken place. What kind of membrane is being used?
Consider the following chemical reaction:
N₂ + 3H₂ --> 2NH₃
a. What are the reactants?
b. What are the products?
c. How many molecules of H₂ are used in the reaction?
a. N₂ + H₂
What is the chemical equation for photosynthesis? What 4 things are necessary for a plant to carry out photosynthesis?
Chemical Equation: 6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂
4 Things Necessary: Light, Carbon Dioxide, Water, and Chlorophyll.
Which of the following is a carbohydrate?
Carbohydrates have only Carbon, Oxygen, and Hydrogen, therefore c. C₂H₄O is the Carbohydrate.
What kind of reaction is used for building disaccharides, polysaccharides, fats, and proteins? What kind of reaction can break these substances down?
A condensation reaction builds them up while hydrolysis breaks them down into their constituent parts.
Describe the pH scale and what it measures.
The pH scale measures the acidity or alkalinity of a solution. On this scale, 7 is neutral. Lower than 7 pH's are acidic, and higher than 7 are alkaline. The low the pH the more acidic, and the pH the more alkaline.
What are the building blocks of proteins, lipids, and polysaccharides?
Amino acids link together to make proteins, fatty acids link to glycerol to make lipids, and monosaccharides link together to make polysaccharides.
If two proteins contain the same type and number of amino acids, but the order in which they link up is different, are the properties of the two proteins the same?
What are enzymes, and for what purpose are they usually used?
Enzymes are a special class of proteins that are used as catalysts.
What is the "lock and key" theory of enzyme action?
It says that an enzyme has an active site that is shaped especially for the molecule that it must work on. The action that the enzyme takes cannot happen until the molecule attaches to that active site.