Term
| Why is biological chemistry important? |
|
Definition
| Understanding the structure and properties of major classes of biological molecules is essential to understanding cellular function at any level. |
|
|
Term
| What are the four classes of biological molecules? |
|
Definition
| Carbohydrates, lipids, proteins, and nucleic acids |
|
|
Term
| What does an atom consists of? |
|
Definition
| A positively charged nucleus and a negatively charged electron cloud |
|
|
Term
|
Definition
| the smallest particle of an element that still retains its distinctive chemical properties |
|
|
Term
|
Definition
| held in orbit by electrostatic attraction to the nucleus |
|
|
Term
| The number of protons in an atom determines ____. |
|
Definition
| its atomic number and its number of electrons |
|
|
Term
|
Definition
| Number of protons plus number of neutrons |
|
|
Term
| What charge does a neutron have? |
|
Definition
| Does not have a charge; neutral |
|
|
Term
|
Definition
| substance that cannot be broken down or converted into other substances by chemical means |
|
|
Term
|
Definition
| atoms linked together to form groups; held together by covalent bonds |
|
|
Term
|
Definition
| element that exist in several physically distinguishable but chemically identical form with each having a different number of neutrons but the same number of protons |
|
|
Term
|
Definition
| an atomic mass unit approximately equal to the mass of a hydrogen atom |
|
|
Term
|
Definition
| 6*10^23; key scale factor describing the relationship between everyday quantities and numbers of individual atoms or molecules |
|
|
Term
|
Definition
| number of molecules that are available to participate in chemical reactions |
|
|
Term
| Which chemical bonds are strong? |
|
Definition
|
|
Term
| Which chemical bonds are weak? |
|
Definition
| Hydrogen, hydrophobic interactions, and Van der Waals attractions |
|
|
Term
|
Definition
| 2 atoms share a pair of electrons |
|
|
Term
|
Definition
| electron donated by one atom to another |
|
|
Term
|
Definition
| pair of electrons shared unequally with one atom attracting the shared electron more than the other |
|
|
Term
|
Definition
| attractive force that occurs between oppositely charged atoms |
|
|
Term
|
Definition
| measured by the amount of energy that must be applied to break a bond, usually expressed in units of either kilocalories per mole or kilojoules per mole |
|
|
Term
|
Definition
| highly specific catalysts |
|
|
Term
|
Definition
| covalent bonds involved in sharing 2 electrons, one donated by each participating atom |
|
|
Term
|
Definition
| Four electrons shared, 2 coming from each participating atom |
|
|
Term
|
Definition
| positive charge is concentrated at one end of the molecule (pole) and the negative charge is concentrated at the other |
|
|
Term
| What kind of bonds does water have? |
|
Definition
|
|
Term
| What kind of bonds does oxygen have? |
|
Definition
|
|
Term
| What can partially shield charges between ionds? |
|
Definition
| The electrical charge effects of water |
|
|
Term
| Why do ionic substances such as sodium chloride dissolve in water? |
|
Definition
| Water molecules are attracted to the positive or negative charge of each ion |
|
|
Term
| The cohesive nature of water is responsible for many of its unusual properties, such as ___. |
|
Definition
| high surface tension, specific heat, and heat of vaporization |
|
|
Term
|
Definition
| electrostatic interaction between a hydrogen held in a polar covalent bind and another atom (usually oxygen or nitrogen) also held in polar covalent bond |
|
|
Term
| Due to the heat energy of the molecules, hydrogen bonds ___. |
|
Definition
| are easily broken by the random thermal motions |
|
|
Term
| In hydrogen bonds, the positively charged region of one water molecule comes close to a ___. |
|
Definition
| negatively charged region of a second water molecule |
|
|
Term
|
Definition
| molecules that are water loving, i.e. sugars, DNA, RNA, and the majority of proteins |
|
|
