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.