Biology 100 Quiz #2
What is the maximum number of single covalent bonds a carbon atom can form with other elements?
4
What are the monomers of proteins?
Amino acids
_____ is the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
Atomic number
_____ is one of the seven elements that make up a small fraction, approximately 3.7%, of living cells.
Calcium
Which of the following classes of large organic molecules includes table sugar?
Carbohydrates
The four elements that make up 96% of living cells
Carbon hydrogen oxygen nitrogen
The chemical name for table salt is sodium chloride, or simply NaCl. What type of chemical is NaCl?
Compound
Why is one side of a single water molecule partially negative while the other side is partially positive?
Electron pairs are unevenly shared between the oxygen atom and the two hydrogen atoms
__________ are substances that CANNOT be broken down into other substances by chemical reactions
Elements
Which cellular process does NOT require energy: Covalent bonds between amino acids Glucose transport through a transmembrane carrier Dehydration reactions in polymer formation Carbohydrate monomers linked to form polysaccharides The Na+/K+ transmembrane protein pumping Na+ ion across the cell membrane
Glucose transport through a transmembrane carrier
Fire can move, grow, reproduce, use energy, consume oxygen, and interact with its environment. Why is it not alive?
It does not have cells. It does not pass on genes or traits to its offspring. It does not consist of complex, well-ordered structures.
Which of the following is not made from long chains of glucose? Cellulose Glycogen Monosaccharides Starch
Monosaccharides
What is typically the first step in the scientific method?
Observation
What kind of bond joins amino acids together to form a protein?
Peptide bond
What are plasma membranes are made of?
Phospholipids
__________ bonds hold the oxygen and hydrogen atoms in a molecule of water together
Polar covalent
Which protein structure is not loss upon denaturation?
Primary structure
A needle can be made to "float" on the surface tension of water. What causes this surface tension to form?
The cohesion of water molecules to each other
Select the most complete explanation of what the pH scale actually measures.
The concentration of hydrogen ions in a solution
What might happen if a protein has a change in one amino acid?
The protein can no longer function properly. The amino acid chain folds incorrectly. The protein has a new shape.
What do you think might happen if you put a mixture of proteins and starch in a solution containing trypsin, an enzyme that breaks down proteins?
The protein would be broken down into amino acids
To a large extent, a protein's function is dependent upon its shape. What determines a protein's shape?
The sequence of amino acids
The majority of the elements essential to life are found in what part of the periodic table?
The top third
_____ , also called micronutrients, are any chemical element required by living organisms in miniscule amounts, but cells require them to survive.
Trace elements
____ is one of the fourteen trace elements and is a component of certain digestive enzymes and other proteins.
Zinc
The number of protons plus neutrons in an atom, represented as an average of all naturally occurring forms of the element, is known as _____ .
atomic weight
Organic compounds are distinguished by molecules that contain ________ bonded to other elements
carbon
A(n) ____ bond involves the sharing of electron pairs between atoms, also known as a molecular bond
covalent
The bond in which bonded atoms share electrons is called a(n) ________.
covalent bond
The building of a large organic molecule from small subunits involves multiple ________.
dehydration synthesis reactions
When two pairs of electrons are shared between two atoms, a ____ bond is formed
double
A college campus-including the students, birds, trees, sidewalks, and air-makes up one complete ________
ecosystem
Organic molecules that end in the suffix "-ase" often function as ________ molecules
enzymatic
In fat synthesis,________and fatty acids combine to make fats plus________.
glycerol water
A weak bond called a ____ bond results from an attraction between a slightly positive region in a molecule and a slightly negative region in the same or a different molecule.
hydrogen
A(n) ____ bond forms when one atom gives up one or more electrons to another atom.
ionic
Atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are ____.
ions
All sodium atoms have 11 protons. The nuclei of some sodium atoms contain 12 neutrons and others contain 11. These different forms of sodium are called __________.
isotopes
Atoms involved in a _____ bond equally share electrons; there is no charge separation to the molecule
nonpolar
A ____ bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms. As a result, one end of the molecule has a slightly negative charge and the other a slightly positive charge
polar
During a chemical reaction, atoms are ________.
rearranged
When one pair of electrons is shared between two atoms, a ____ bond is formed.
single
The most unsaturated fats have ...
the most double bonds.
