Unit One Bio 1090 Mastering
Triglycerides vary with respect to the number of ...
(a) C atoms in the tails. (b) double bonds in the tails.
The presence of many C-C and C-H bonds causes fats to be ...
(a) rich in energy. (b) insoluble in water.
Which number represents the atomic weight of oxygen? 8 O Oxygen 16.00
16
What is the maximum number of single covalent bonds a carbon atom can form with other elements?
4
How many neutrons are in a typical oxygen atom? 8 O Oxygen 16.00
8
While the maximum number of electrons required to fill the outermost shell of an atom varies depending on the size of the atom, almost all of the smaller atoms (atomic numbers 2-20) are considered stable (nonreactive) when they contain ________ electron(s) in the outermost shell.
8
What is the basic structure of typical dietary fats?
A glycerol head and up to three fatty acid tails
Why are all living organisms based on molecules that contain carbon?
Carbon atoms can form strong covalent bonds with many other carbon atoms, and the atoms of hydrogen, oxygen, and nitrogen.
Water is sometimes called the "universal solvent." Is that accurate?
For the most part. Water readily dissolves most substances, but not hydrophobic ones.
Water "beads up" on synthetic fabric like polyester but binds to cotton. What is the most likely explanation for this?
Polyester is nonpolar, whereas cotton is polar.
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
Which best describes how charges are distributed on a water molecule?
The oxygen end is negative relative to the end with the two hydrogen atoms
To a large extent, a protein's function is dependent upon its shape. What determines a protein's shape?
The sequence of amino acids
Relative to other substances, water tends to resist changes in temperature. Why?
Water is highly cohesive. Its molecules tend to resist increases in their motion. When water is heated, some of the energy is used to disturb the hydrogen bonds between neighboring molecules.
What is responsible for the unusual chemical properties of water?
Water molecules can form an extensive network of hydrogen bonds with one another.
Something with a pH of 5 would be ________
acidic
Water readily sticks to many other substances, a property called ______.
adhesion
What are the monomers of proteins?
amino acids
The smallest unit of matter that retain all of the physical properties of that type of matter is a(n)
atom
_________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
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
is one of the seven elements that make up a small fraction, approximately 3.7%, of living cells.
calcium
Based on the suffix, a molecule of "maltose" is most likely what type of macromolecule?
carbohydrate
Organic compounds are distinguished by molecules that contain ________ bonded to other elements.
carbon
The scientific study of matter is called
chemistry
Water striders are common insects that can skip across the surface of ponds and streams. This lifestyle is enabled by water's _____.
cohesion and resulting surface tension
_____ bond involves the sharing of electron pairs between atoms, also known as a molecular bond.
covalent
When two pairs of electrons are shared between two atoms, a _______bond is formed.
double
H2SO4, sulfuric acid, contains three different types of atoms: hydrogen (H), sulfur (S), and oxygen (O). Each of these atoms represents a different _______. Since the three types are combined in a fixed ratio, this means that H2SO4 is a(n) _______
element compound
_________ are substances that CANNOT be broken down into other substances by chemical reactions.
elements
Proteins are diverse molecules that perform a wide variety of functions. Which of the following is not a typical function of proteins?
energy storage
Water is the least dense when it ________.
freezes
Starch and glycogen are complex carbohydrates made by joining together long chains of __________ monomers.
glucose
Which of the following represents a simple sugar (also called monosaccharides)?
glucose
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
All lipids are ________.
hydrophobic
the reaction that builds a fat,________ groups react with ________ groups.
hydroxyl; carboxyl
If the number of protons in an atom does not match the number of electrons, the atom is specifically called an _______
ion
A(n) _______bond forms when one atom gives up one or more electrons to another atom.
ionic
In an atom, the number of neutrons determines most specifically the ________.
isotope
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
A food company hydrogenated a barrel of fat. The treatment ...
made the fat less fluid.
is anything that occupies space and/or has any substance.
matter
If two or more atoms are bonded together, they form
molecule
Which of the following is not made from long chains of glucose?
monosaccharides
is one of the four elements that make up 96.3% of living cells
nitrogen
Atoms involved in a ________bond equally share electrons; there is no charge separation to the molecule.
non polar
What is the most common element in your body?
oxygen
________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
What is another name for the polymers of carbohydrates?
polysaccharides
Enzymes are a type of ____
protein
If you were to write out this chemical reaction, water and carbon dioxide are each an example of a(n) _______ while glucose and oxygen are each an example of a(n) _______
reactant product
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.
The part of the atom that most determines the chemical properties of the atom.
the number of electrons
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