A&P I - Unit One, Chapter Two
What are examples of lipids?
Phospholipids Steroids Triglycerides Fatty acids
Which important properties of water allow it to support life?
Solvency Chemical reactivity Cohesion
The body's most important energy-transfer molecule is ______.
ATP
The energy molecule that is produced by cellular respiration and used in metabolic reactions is ______.
ATP
A tissue fluid pH below 7.35 is defined as a state of ______.
Acidosis
Which three functional groups are part of the basic structure of every amino acid?
Amino group Radical (R group) Carboxyl group
Which is an enzyme?
Amylase (enzymes end in -ase)
The chlorine atom gains electrons to become a chloride ______.
Anion
What is the term for an ion with a net negative charge (more electrons than protons)?
Anion
Which term refers to a chemical that binds protons in a solution and functions as a proton acceptor?
Base
Which of the following is another term for enzyme?
Biological catalyst
Solution A prevents solution C from changing its pH. Solution A is therefore a what?
Buffer
The ______ family of macromolecules are composed of carbon, hydrogen and oxygen in a 1:2:1 ratio and includes sugars, starches, glycogen, and cellulose.
Carbohydrate
Indicate how pH and temperature affect the activity of an enzyme.
Causing a conformational change in the enzyme Altering the shape of the substrate binding site
The ability of water to dissolve other chemicals is ______.
solvency
The lock and key model describes the property of enzyme-substrate
specificity
A ____ is the substance that an enzyme acts upon.
substrate
pH is a measurement of the concentration of what?
Hydrogen ions
Which organic molecules are composed of a nitrogenous base, a monosaccharide, and a phosphate group?
Nucleotides
Which of the following best defines an acid?
Proton donor
The atomic mass of an element is approximately equal to the total number of which two subatomic particles?
Protons Neutrons
Describe respiratory compensation in response to alkalosis.
Pulmonary ventilation rate decreases.
How can the respiratory system compensate for a drop in blood H+ concentrations?
Reduced pulmonary ventilation allows CO2 to accumulate, lowering the pH back to normal.
The addition of CO2 to the body fluids raises H+ concentration and lowers pH, while the removal of CO2 has the opposite effect. This is the basis for the strong buffering capacity of which system?
Respiratory system
Which two organ systems form physiological buffers that help stabilize pH by controlling the body's output of acids, bases, or CO2? Select two options from the list below.
Respiratory system Urinary system
What are the major chemical buffer systems of the body? Select three options from the list below.
The phosphate buffer system The bicarbonate buffer system The protein buffer system
HCl is a compound that releases hydrogen ions when put into water. Therefore, it is a(n) ______.
acid
The energy required to initiate or begin a chemical reaction is called its _____ energy
activation
The substrate-binding site of an enzyme is known as the _____ site
activation
Slight deviations from the body's normal _______ range can shut down metabolic pathways as well as alter the structure and function of other macromolecules. Buffer systems help to avoid this.
pH
A cation has a net _____ charge
positive
Which type of buffer is defined as a substance that binds H+ and removes it from solution as its concentration begins to rise, or releases H+ into solution as its concentration falls?
Chemical
Water molecules are weakly attracted to each other through ______ bonds.
Hydrogen
Which of the following best describes the chemical reaction called hydrolysis?
A covalent bond is broken by adding an OH to one side of the molecule, and an H to the other side.
Which term can apply to a molecule composed of two or more different elements?
Compound
Which type of bond is formed by the sharing of a pair of electrons between two atoms?
Covalent
In many biochemical reactions, individual subunits are joined to form larger macromolecules with the release of water molecules. How are these reactions classified?
Dehydration synthesis reactions
Which subatomic particle does not contribute significantly to the mass of an atom?
Electron
Each enzyme catalyzes one particular chemical reaction. Which term describes this property of enzymes?
Enzyme-substrate specificity
Which of the following statements about enzymes are true?
Enzymes show enzyme-substrate specificity. Enzymes are not consumed in the reactions they catalyze. Enzymes speed up reaction rates by lowering the activation energy of a specific reaction.
A chemical bond that involves the attraction of a cation to an anion is called a(n) ___ bond.
Ionic
Which type of chemical bond involves the exchange of electrons?
Ionic
Atoms of the same element that differ only in the number of neutrons are known as
Isotopes
Which are true regarding respiratory compensation?
It is effective in correcting for PCO2 imbalances. It corrects the pH of body fluids by expelling or retaining CO2.
Why is it important to maintain the pH of blood and tissue fluids within normal limits?
The structure and function of macromolecules depend on pH levels and a slight deviation in pH can shut down the metabolic pathways
Which of the following best describes denaturation?
The unfolding of a protein's three-dimensional shape
Which system buffers the greatest quantity of acid or base but requires several hours to days to exert an effect?
Urinary system
NaOH is a compound that releases hydroxide ions in water. Therefore, it is a(n) ______.
base
Nucleotides contain a phosphate, a sugar and a nitrogenous
base
In nature, sodium atoms lose electrons; therefore, they become ______.
cations
A pure chemical substance that consists of one type of atom is called a(n)
element
