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57 terms

Biology Test 2

know about Metabolism
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nucleus
Most of the mass of an atom is contained in its
protons
Atomic mass is determined by the number of neutrons plus
element
The number of protons in an atom determines the
neutral
Atoms are electrically ________ because they have the same number of protons and electrons.
nitrogen
The principal elements found in living things are carbon, hydrogen, oxygen, and
molecule
the smallest complete unit of a compound or diatomic gas
compound
a new substance formed by the combination of two or more different atoms
energy
area that electrons are found around an atomic nucleus
17
The atomic mass of an element whose atoms consist of eight protons, nine neutrons, and eight electrons is:
118
how many elements have been identified?
gains
When an atom ____ an electron, it becomes charged.
ion
An atom that has gained or lost electrons is called an ___
salt
____ is produced when an acid reacts with a base.
electrons
The reactivity of an atom is due to the number and arrangement of ______ in the outer energy level.
covalent
The bond that includes sharing electrons with another atom is called
positively
When an atom loses an electron, it becomes _______ charged
ionic
Atoms which transfer electrons can combine to form a(n) _______ bond.
Chemical reactions
_________ _______ are the result of an atom attempting to rearrange its configuration to result in a stable octet.
organic
Water can dissolve only _______ compounds.
acid
are compounds that produce H+ ions in solution. A substance which yields an anion plus a proton is a(n)
electrons
When atoms combine, interactions occur between their
hydrogen
The bonds that link many water molecules together to form a water drop are _______. The weak type of bonding which attracts molecules to molecules is ______.
covalent
When electrons are shared, the type of bonding is called
activation energy
The heat needed for chemical reaction to take place is called
catalyst
A substance that helps a reaction to take place, but does not participate in the reaction is called a
decomposition
H2CO3 ------> H2O + CO2
synthesis
NH3 + H2O -------->NH4OH occurs when a molecule is formed from the bonding of atoms, ions or simpler molecules.
exchange
H2SO4 + 2KOH --------->K2SO4 + 2H2O reaction occurs when the bonds of the reacting compounds are broken and new combinations are formed. Acid + base yields salt + water
buffers
Substances which maintain a body's pH within narrow limits are called
energy output
What is expected when reactants break bonds?
hydrolysis
decomposition using water. Carbohydrates are converted to energy by the process of ________.
complex
Polysaccharides are ______ sugars
phospholipids
Of the three liquid types, _________ are more similar to fats
DNA
The ___ bases are attached to the phosphate part of the structure.
nucleic acids
carry the genetic codes which determine the structure and function of an organic compound
carbohydrates
Lipids are chemically most similar to
5,000
In a protein molecule, the number of amino acid molecules may be as many as:`
protein
Enzyme, antibody, hormone, and muscle are roles played by
nucleic acids
The largest molecules in organisms are
4
How many electrons does carbon lack in its outer shell?
ionic
When compounds which are formed from _____ bonds decompose, the products are usually ions of the original elements
polymers
Large organic molecules which are synthesized from multiple identical subunits are carbohydrates, proteins, nucleic acids, and _______
lipids
Steroids are
proteins
Amino acids are the building blocks of
covalent
Carbon forms ______ bonds.
nucleic acids
The largest organic molecules are _______ ____
enzymes
Protein catalysts which cause reactions to occur at temperatures and pH values which are common to living cells are called _______. Are produced within an active cell. An organism can NOT live without ______. A catalyst for chemical reactions in biological systems is called an _______.
cofactors
Nonprotein substances (such as vitamins and some metal ions) which need to be present for enzymes to function are called
ionic
transfer
covalent
sharing
carbohydrate
A sugar or polymer of sugar.
lipid
A group of organic compounds including fats, steroids, and phospholipids.
nucleic acid
A sequence of sugars, phosphates and nitrogenous organic bases: DNA and RNA.
polymer
A chemical compound in which each molecule is made up of two or more simpler molecules strung together.
polymerization
A reaction in which two or more molecules unite, forming a more complex molecule.
protein
A large complex organic molecule consisting of a large number of amino acids linked together by peptide bonds.
RNA
an acid located in the cell nucleus