Chapter 2 Mastering

A buffer consists of undissociated acid (HA) and the ion made by dissociating the acid (A-). How does this system buffer a solution against decreases in pH? (a) HA dissociates and releases H+ and A- into solution. (b) A- reacts with H+ to become HA. (c) As the solution loses H+, HA replaces the lost H+. Both (a) and (c). None of the above.

(b) A- reacts with H+ to become HA. (A- binds most of the added H+ so not much H+ is left to lower pH)

When the electrons located in the outermost electron shells of atoms interact, ___ are formed. *chemical bonds *solutions *isotopes *isomers

chemical bonds

In DNA, a guanine base will match with

cytosine base

Enzyme-substrate Interaction(put in order) *The substrates bind the enzyme, both the substrates & the enzyme change shape. *Product & enzyme dissociate & enzyme changes shape *Substrates enter transition state & are converted into products. *The substrates approach the enzyme.

*The substrates approach the enzyme. *The substrates bind the enzyme, both the substrates & the enzyme change shape. *Substrates enter transition state & are converted into products. *Product & enzyme dissociate & enzyme changes shape

The fatty acid w/ a double bond & bent hydrocarbon chain (looks like a bent yard stick) *would be the predominant type of fatty acid in animal fats *contains multiple double bonds in its hydrocarbon chain *is saturated

*is liquid at room temperature (Monounsaturated fatty acids like this one are generally liquid at room temperature because their bent hydrocarbon chains cannot pack tightly together)

Which two functional groups are always found in amino acids? *Amino and carboxylic acid *Amino and carbonyl *Hydroxyl and carboxylic acid *Carbonyl and phosphate

Amino and carboxylic acid

In an exergonic reaction, ___ *excess energy stored in the reactants is released, leaving products with more energy than the reactants *energy is invested into the reaction, so the products have more energy than the reactants *energy is invested into the reaction, so the products have less energy than the reactants *excess energy stored in the reactants is released, leaving the products with less energy than the reactants

excess energy stored in the reactants is released, leaving the products with less energy than the reactants (reactants have more energy than needed so extra energy is released)

The amniotic fluid that surrounds a developing fetus helps protect the fetus by all the following except: *exchanging gases between the fetus and the mother. *maintaining a stable temperature around the fetus. *cushioning the fetus from mechanical trauma. *keeping the fetus buoyant.

exchanging gases between the fetus and the mother. (this is the primary function of the placenta)

Which of the following molecules is not considered a polymer? *fatty acid *protein *nucleic acid *polysaccharide

fatty acid (it's a basic lipid monomer that consists of a carboxylic acid group bonded to a hydrocarbon chain. Hydrocarbon chain may have one or more double bonds between its carbon atoms, which is a convenient way to classify fatty acids)

A compound that would be most soluble in water would be: *cholesterol. *a large protein. *a triglyceride. *glucose

glucose (most soluble because it has many polar hydroxyl groups which can hydrogen bond with water molecules)

In fat synthesis,________and fatty acids combine to make fats plus________. glucose; phosphate phosphate; glycerol esters; phosphate esters; water glycerol; water

glycerol; water (Water is a by-product of the reaction that makes ester links between glycerol and fatty acids.)

All of the following are basic types of chemical reactions except: *homeostatic reactions. *catabolic reactions. *exchange reactions. *anabolic reactions.

homeostatic reactions

What are the four major elements found in the human body?

hydrogen (10%), oxygen(65%), carbon (18%), nitrogen (3%)

Bonds between neighboring water moledules are __________ bonds.

hydrogen bonds

Of the 92 naturally occuring elements, the four major elements that make up 96% of living things are:

hydrogen, oxygen, nitrogen, carbon

A ______ reaction involves the addition of water to break down large molecules into smaller molecules. *hydrolysis *dehydration synthesis *anabolic *exchange

hydrolysis

Molecules or compounds that will not dissolve easily in water are ____.

hydrophobic

In the reaction that builds a fat,________ groups react with ________ groups. *carboxyl; amino *hydroxyl; carboxyl *phosphate; amino *sulfhydryl; carboxyl *hydroxyl; phosphate

hydroxyl; carboxyl (Fatty acids supply the carboxyl group; the hydroxyls come from glycerol)

Atoms that satisfy the octet rule are said to be____. *inert *reactive *isotopes *ions

inert

Organic and inorganic compounds differ in that: *inorganic compounds usually lack carbon. *inorganic compounds usually contain carbon. *inorganic molecules are usually large and complex. *inorganic molecules are used by the body to perform complex functions.

inorganic compounds usually lack carbon

An atom that has either gained or lost electron(s)

ion (formed when they gain/lose electrons to attain a full valence shell, giving electrical charge. Can be stored in body, such as ions of calcium & phosphate in bones, or be available individually for physiological processes. Na+ required for muscle contraction, nerve impulse conduction, & regulation of blood pressure)

Ions of opposite electrical charges are attracted to each other to balance the charges & it forms a ____bond.

ionic bond

Sodium Chloride (NaCl) is an example of a _________ bond

ionic bond (Ionic bonds involve transfer of electrons, which creates a positively charged ion and a negatively charged ion. The two oppositely charged ions attract each other & is called ionic bond)

Salts are held together by

ionic bonds

Atoms that have the same number of protons but a different number of neutrons are called?

isotopes

Atoms with the same atomic number (protons) but different mass numbers (protons+neutrons) are called

isotopes

DNA contains all of the following structural features except: *it contains uracil. *it contains deoxyribose sugar. *it forms a double helix. *it forms hydrogen bonds between bases.

it contains uracil (RNA contains uracil)

All of the following properties are associated with water except: *it is an organic molecule. *it is involved in synthesis and hydrolysis reactions. *it is a solvent. *it has a high heat capacity.

it is an organic molecule

Though you add heat, the temperature of boiling water remains constant because ...

it takes energy to break hydrogen bonds (the departing steam carries away all the added energy with none left to raise temperature)

Prions are infectious particles that can cause normal proteins to assume a misfolded shape. When proteins assume an abnormal three-dimensional shape, they: *lose their primary structure *lose their function *become unstable *become enzymes

lose their function (protein loses shape =loses its function)

Most biological molecules are stable & nonreactive to:

maintain their structure and function in the body.

Anything that takes up space and has mass is known as:

matter

Building blocks of organic molecules are known as ____. *monomers *electrolytes *polymers *enzymes

monomers

The monomer of carbohydrates is ___.

monosaccharide

Enzyme deficiencies can be extremely damaging to the body's homeostasis and may be caused by: *low body temperatures. *a lack of substrate. *high levels of kinetic energy. *a mutation in a gene.

mutation in a gene (Most enzymes are proteins. Structure of every protein is coded for by the DNA in the genes. DNA code for enzyme is mutated, then the structure will change. Enzyme structure is very specific for its function so change could render it nonfunctional.)

A ___ is made of nitrogenous base, pentose sugar and a phosphate group.

neucleotide

Which subatomic particles contribute to an atom's mass number but not its atomic number?

neutrons

A ___ forms when electrons are shared equally among the atoms in a bond.

non polar covalent bond

C2H6 is a(n)

nonpolar covalent molecule (if a molecule has only carbon & hydrogen it's nonpolar covalent)

The group of polymers that contribute the smallest mass to the human body but are the most important because they are responsible for storage & execution of the genetic code are the: *nucleic acids. *proteins. *carbohydrates. *lipids.

nucleic acids

What predicts the element to which an atom belongs?

number of protons

The atomic number for each element on the periodic table represents the:

number of protons in the atom

When an ionic bond forms, which part(s) of atoms are directly involved?

outermost electrons (valence electrons)

The four most common elements, comprising 96% of human body's mass are:

oxygen, nitrogen, hydrogen, and carbon

On the pH scale, which number has the highest concentration of hydrogen ions? *pH 1 *pH 5 *pH 7 *pH 10

pH 1

Alanine & glycine go through dehydration synthesis & create a dipeptide which forms a ____bond.

peptide

A ____ is a polar covalent bond that joins two amino acids together through a synthesis reaction. *peptide bond *glycosidic linkage *ester linkage *phosphodiester bond

peptide bond (Glyosidic linkage is a covalent bond that joins two monosaccharides through synthesis reaction, Ester linkage is a covalent bond that forms between the carvoxylic acid on a fatty acid & the hydroxyl group on glycerol molecule (ex.triglyceride), phosphodiester bond is a covalent bond which a phosphate group bonds adjacent carbons through an ester linkage (ex.nucleic acids))

The primary lipid in cell membranes is: *phospholipid. *triglyceride. *cholesterol. *steroid.

phospholipid (Triglycerides are neutral fats w/ 3 fatty acid chains, cholesterol is basis for body's steroids, Steroids are lipids consisting of a core of 4 hydrocarbon rings attached to other chemical groups)

An individual water molecule is formed by a ____ bond.

polar covalent bond

What type of chemical bond forms when electrons are shared unequally between two atoms?

polar covalent bond

Which parts of atoms can interact (react) to form chemical bonds?

valence electrons

A hydrogen acceptor in a solution is called a ____. *base. *acid. *buffer. *salt.

Base (hydrogen accepter, acid is hydrogen donator)

What is the function of a buffer? *Buffers prevent large swings in pH when an acid or base is added to a solution. *Buffers lower the activation energy of a chemical reaction. *Buffers act as a lubricant between two adjacent surfaces. *Buffers absorb heat without changing temperature themselves.

Buffers prevent large swings in pH when an acid or base is added to a solution

Of the subatomic particles, which one is positively charged?

Protons

What contributes to the calculation of mass number

Protons + Neutrons

Which two organ systems work to maintain pH balance in the body?

Respiratory & Urinary

The more hydrogen ions present in a solution, the more ___ the solution. *acidic *basic *neutral *alkaline

acidic

Formation of hydrogen bonds requires hydrogen atoms and what else?

polar covalent bonds

The chemical properties of an atom-in other words, how likely it is to form bonds and what types of bonds it will form--depends on its___________.

valence electrons

What determines how an atom interacts with other atoms and whether it will form bonds with specific atoms?

valence electrons

A food company hydrogenated a barrel of fat. The treatment .. (a) made the fat less fluid. (b) made the fat less saturated.(c) lengthened the fat tails. (d) put more bends (kinks) in the fat tails. Both (a) and (d).

(a) made the fat less fluid. (Hydrogenation removes double bonds so tails can straighten allowing them to fit closely together & therefore be less fluid)

Which statement is true of water's tensile strength? (a) It results from hydrogen bonding. (b) It helps to pull water through plants. (c) It involves both cohesion and adhesion. Both (a) and (b). (a), (b), and (c).

(a), (b), and (c). (a) It results from hydrogen bonding. (b) It helps to pull water through plants. (c) It involves both cohesion and adhesion. (Hydrogen bonding, water coheres to itself & adheres to cell walls making it possible to pull water through plants without breaking water column)

Polymers that contain sugars ... (a) may store hereditary information. (b) may store energy. (c) may protect cells. Both (b) and (c). (a), (b), and (c).

(a), (b), and (c). (a) may store hereditary information. (b) may store energy. (c) may protect cells. (they also lubricate the path of roots through soil and they glue plant cells together)

What do fats, steroids, and waxes have in common? (a) Moderate polarity. (b) Low solubility in water. (c) They occur in membranes. Both (a) and (c). Both (b) and (c).

(b) Low solubility in water. (Low water solubility is the trait that defines lipids)

Why doesn't oil mix with water? (a) Nonpolar molecules repel water molecules. (b) Polar molecules repel nonpolar molecules. (c) Polar molecules attract one another. (d) Nonpolar molecules attract one another. Both (a) and (d).

(c) Polar molecules attract one another. (Cling to one another & won't part to make room for uncharged (nonpolar) molecules. There's no repulsion)

Why is it important to monitor a high fever and not allow it to persist over a long period of time? *High temperatures associated with a fever can denature important enzymes. *High temperatures associated with a fever can increase water intake. *High temperatures associated with a fever can increase appetite causing adverse effects. *High temperatures associated with a fever can prevent the infection from going away.

*High temperatures associated with a fever can denature important enzymes. (raising temp of reactants increases kinetic energy of atoms resulting in more forceful & effective collisions. Many substances in human body are destroyed at high temps. Enzymes can lose their structure or are denatured)

Calcium's atomic number is 20. It forms ions with 18 electrons. What is the electrical charge of a calcium ion?

+2

How many amino acids are there?

20 different amino acids (R group varies in amino acids)

Determine the number of protons in an isotope of nitrogen with an atomic number of 7 and a mass number of 14.

7

An atom of oxygen has an atomic number of 8 and a mass number of 18. How many of each type of subatomic particle does it contain?

8 protons, 8 electrons, and 10 neutrons

Sodium (Na) atoms have a single valence electron, and so each of these atoms has only one electron to share. Which of the following is true? *A molecule of sodium (Na) will not exist in nature *Sodium is stable & unreactive *Sodium will share its one electron with seven other atoms *Sodium will share its one electron with hydrogen

A molecule of sodium will not exist in nature.

What helps to explain why water has a high specific heat

A water molecule can make 4 hydrogen bonds

Which of the following represents an exchange reaction? AB + CD → AD + BC AB + CD → BA + DC AB → A + B A + B → AB

AB + CD → AD + BC

_____ is the main source of chemical energy that drives all cellular work and belongs to the class of organic molecules known as _______. *ATP; nucleic acids *Glucose; carbohydrates *Triglycerides; lipids *Collagen; proteins

ATP; nucleic acids

The input of energy required so that the reactants reach their transition states & form products?

Activation energy

What helps to explain why all living cells need pH buffers?

Amino acid side chains have many carboxyl and amino groups (when these side chains ionize, they exert forces that affect protein's folding. If pH isn't stabilized, the proteins will change their folding & may not function properly)

Describe structure of amino acid.

Amino acid/R group/Carboxyllic acid group

Which of the following molecules is a lipid with a four-ring hydrocarbon structure? *Purine *Fatty acid *Triglyceride *Cholesterol

Cholesterol (member of steroid class, which all share a four-ring hydrocarbon structure)

A ____ bond involves the sharing of one to three pairs of electrons

Covalent bond

Atoms share one or more pairs of electrons in a ____ bond.

Covalent bond

Rank the types of chemical bonds, in order, from strongest to weakest

Covalent, ionic, hydrogen

Which of the following molecules contains polar covalent bonds? CH4 H2 H20 NaCl

H2O (CH4 - nonpolar covalent bond, H2 - nonpolar covalent bond, NaCl - ionic bond)

Which is an exchange reaction? *dehydration *C6H12O6+C6H12O6→C12H24O12 *HCl+NaOH→NaCl+H2OHCl+NaOH→NaCl+H2O *hydrolysis

HCl+NaOH→NaCl+H2O

Water has surface tension because ...

Hydrogen bonds between surface water molecules resist being stretched (Bonds are normally slightly stretched, like a stretched sheet of rubber, surface tends to contract & resist being penetrated)

Which of the following increases the rate of a reaction? *Increased reactant concentration *Cold temperatures *Absence of a catalyst *Solid reactants

Increased reactant concentration

How does the way a buffer stabilizes pH during addition of acid differ from the way the same buffer stabilizes pH during addition of base?

It's the same reaction running backward or foward

Atoms of oxygen have a total of 8 electrons. Are these atoms stable, and why or why not?

No, because the atoms have only 6 valence electrons, but need 8 for stability.

Is it possible for a molecule of hydrogen (H2) to form a hydrogen bond?

No, since a molecule of hydrogen (H2) forms a nonpolar covalent bond.

H2 is an example of a ____ bond.

Non polar covalent bond (The two hydrogen atoms share a pair of electrons equally because both share the same electronegativity.

Which of the following statements concerning protein structure is incorrect? *The quaternary structure is present in all proteins and consists of the combination of several polypeptide chains. *The tertiary structure refers to the three-dimensional shape of the protein. *The secondary structure consist of a twisting or folding peptide chain. *The primary structure of a chain consists of amino acids joined by peptide bonds.

The quaternary structure is present in all proteins and consists of the combination of several polypeptide chains.

Which statement is true of pH buffers? (a) They consist of strong acids and strong bases. (b) They keep the pH of the blood constant. (c) They consist of weak acids and weak bases. Both (a) and (b). Both (b) and (c).

They consist of weak acids and weak bases. (using weak acids & bases, the buffer can absorb or give off H+ to stabilize pH)

What do DNA, proteins, and fats have in common? *They are polymers. *They are polar. *They contain carbonyl groups. *They contain phosphorus. *They contain nitrogen.

They contain carbonyl groups.

T/F Proteins are polymers made out of amino acids.

True

T/F Water is a unique solvent for body that dissolves salt, glucose, and amino acids.

True

Which of the following is not a result of hydrogen bonds? *An enzyme has a unique shape that allows it to bond only with specific molecules. *Two strands of DNA are linked together taking a shape similar to a ladder. *Some hair is straight, some wavy, and some very curly. *Two hydrogen atoms join together to form a molecule of hydrogen gas.

Two hydrogen atoms join together to form a molecule of hydrogen gas. (Hydrogen bonds occur when there are polar covalent molecules present, but they join through nonpolar covalent bonds)

Carbon atoms have four valence electrons. Are they likely to react with other atoms, and why or why not?

Yes, because they can become more stable by doing so.

Dr. Haxton told one of his students, "To move in the bloodstream, fats need the help of phospholipids." What would a good student say? *Not so. Fats are small enough to travel easily without help. *Yes. Nonpolar molecules aren't compatible with water. *You have it backwards. Fats help phospholipids to travel. *Sorry, Dr. Haxton! Help comes from cholesterol, not phospholipids. *Right. Fats are too polar to travel alone in water.

Yes. Nonpolar molecules aren't compatible with water. (Water rejects nonpola molecules such as fats, so fats travel inside particles that are coated with polar parts of phopholipids & proteins)

Buffers work best when ... *nearly all of the buffer molecules are undissociated. *nearly all of the buffer molecules are dissociated. *about half of the buffer molecules are dissociated. *the pH is nearly neutral. *the ratio of H+ to OH- is close to 1.0.

about half of the buffer molecules are dissociated

Saturated, monounsaturated, and polyunsaturated fats differ in the: *absence or number of double *covalent bonds present. *presence or absence of ester linkages. *number of carboxyl groups. number of carbon atoms.

absence or number of double covalent bonds present

Nitrogenous bases found in RNA?

adenine, guanine, cytosine, and uracil

Nitrogenous bases found in DNA

adenine, guanine, cytosine, thymine

The four nitrogenous bases found in DNA are:

adenine, guanine, cytosine, thymine

When blood pH rises above 7.45, the body systems suffer from ____. *alkalosis *acidosis *buffering *The blood is not affected by changes in pH.

alkalosis (acidosis is under a pH of 7.35 or lower)

Formation of a cation and an anion is indicative of

an ionic bond

The synthesis reactions that take place in the body are referred to as __ reactions, whereas the decomposition reactions are referred to as __ reactions.

anabolic; catabolic

Which of the following is not produced through chemical bonding? *the heart *cells *adipose (fat) tissue *atoms

atoms (Atoms react through chemical bonding to form larger structures. Chemical bonding begins with atoms; does not produce them.

When an atom loses an electron it is called a(n) ____; when an atom gains an electron it is called a(n)___. *cation; anion *anion; cation *polar; nonpolar *nonpolar; polar

cation; anion

While exercising, your body temperature increases, causing you to feel hot and begin sweating. This increase in temperature occurs because:

chemical energy is converted to mechanical energy allowing the motion to occur.

Poisons that function by inhibiting a cell's enzyme could potentially be lethal because:

chemical reactions would proceed too slow to maintain life.

The open spaces in water's crystal structure makes it possible for (a) aquatic life to exist at the North Pole. (b) water to have a low boiling point. (c) life to occur in hot springs. Both (b) and (c). (a), (b), and (c).

(a) aquatic life to exist at the North Pole. (Lattice makes ice less dense than liquid water so it floats. Causes water to freeze from top down so there's always liquid in which organisms can live)

Mass number of an atom is calculated how?

portons + neutrons

Which of the following is the same among isotopes of the same element? *Atomic number *Number of neutrons *Mass number *Both the number of neutrons and the mass number

Atomic number

Water is a source of___ for chemical reactions in cells. (a) hydrogen atoms (b) oxygen atoms (c) energy Both (a) and (b) (a), (b), and (c).

Both (a) and (b (a) hydrogen atoms (b) oxygen atoms

Which statement helps to explain why ice is less dense than liquid water? (a) Water molecules make hydrogen bonds at definite angles. (b) Cold molecules move less than warm molecules. (c) Hydrogen bonds lengthen in the cold. All of the above. Both (a) and (b).

Both (a) and (b). (a) Water molecules make hydrogen bonds at definite angles. (b) Cold molecules move less than warm molecules (The ice lattice has open spaces because of the angles which hydrogen bonds form)

The presence of many C-C and C-H bonds causes fats to be... (a) rich in energy. (b) insoluble in water. (c) low in energy. Both (a) and (b). Both (b) and (c).

Both (a) and (b). (a) rich in energy. (b) insoluble in water. (many C-C and C-H bonds make fats nonpolar and insoluble in water. They can also be oxidized, releasing much energy)

Which factor is important in making it possible to cool yourself by sweating? Think carefully! a) Molecules collide with varied angles and speeds. (b) Hydrogen bonds are relatively weak. (c) Water has more energy at the body surface. Both (a) and (b). (a), (b), and (c).

Both (a) and (b). a) Molecules collide with varied angles and speeds. (b) Hydrogen bonds are relatively weak. (Random collisions allow some molecules to accumulate more energy that others. Weakness of hydrogen bonds lets those molecules escape, leaving cooler molecules behind.

Triglycerides vary with respect to the number of .. (a) hydrocarbon tails. (b) C atoms in the tails. (c) double bonds in the tails. Both (b) and (c). All of the above.

Both (b) and (c). (b) C atoms in the tails. (c) double bonds in the tails. (Tail lengths of 16-22 are common. May be 0-6 double bonds)

Which of the following terms is NOT defined as one of the three basic types of mixtures? *Buffers *Colloids *Solutions *Suspensions

Buffers

DNA/RNA, which contains deoxyribose & which contains ribose?

DNA, contains deoxyribose & double helix RNA, contains ribose & single strand

Anabolic reaction in which two monomers are linked by a covalent bond and a water molecule is formed.

Dehydration synthesis

____ is what occurs when a protein's structure and function is lost because of exposure to extreme heat or chemical factors. *Denaturation *Renaturation *Synthesis *Oxidation

Denaturation

When two electron pairs are shared between atoms a __ is formed.

Double bond

Which of the following is true of polar covalent bonds? *Electrons are shared unequally *They are rather weak bonds *The same number of electrons are gained by one atom as are lost by another *Electrons are shared equally

Electrons are shared unequally (& they spend more time around one atom than the other, causing slight negative charge where they tend to hang out the most, positive charge where they spend least time)

What type of reaction is A + B -->AB

Enderdonic

Which statement best describes enzyme function? *Enzymes speed chemical reactions by lowering the activation energy. *One enzyme can work on thousands of different substrates. *Enzymes can perform catabolic reactions only. *Enzymes chemically alter both the reactants and products.

Enzymes speed chemical reactions by lowering the activation energy.

Which of the following distinguishes hydrogen bonds from covalent bonds? *Only ionic bonds can form within molecules. *Only covalent bonds can form between molecules. *Only hydrogen bonds can form within molecules. *Only hydrogen bonds can form between molecules.

Only hydrogen bonds can form between molecules. (Because hydrogen bonds are not true bonds-they are weak attractions due to imbalance- they do not always join atoms together within a single molecule. Bonding molecules together is an inter molecular attraction)

Which statement must be mentioned in explaining why amphipathic molecules line up at a water surface? *Polar groups repel water. *Polar groups attract one another. *Nonpolar groups repel water. *Nonpolar groups attract one another.All of the above.

Polar groups attract one another (Polar water molecules pull together, holding polar parts of amphipathic molecules & squeezing out nonpolar parts)

In the following chemical reaction, what is NaCl? NaOH + HCl --> NaCl + H20 *Product *Acid *Water *Reactant

Product

Amino acids are the monomers for ____. *proteins *carbohydrates *lipids *nucleic acids

Proteins

A ___ mixture that generally consists of a liquid mixed with a solid.

Suspension

Blood is a mixture of fluid and insoluble particles that are large enough to be visible, such as blood cells and platelets. Therefore, blood is a _______.

Suspension

Which of the following are especially important for growth and repair processes? *exchange reactions *synthesis reactions *hydrolysis

Synthesis reactions

What chemical binds free hydrogen ions in a solution? *Base *Acid *Salt *Water

base

A weak acid or a weak base half ionized in water is necessary to make a ___.

buffer (when half of molecules are ionized, there are plenty of molecules that can either absorb or give off H+ when pH is disturbed from outside)

Hydrolysis is an example of which type of reaction?

decomposition

Two smaller molecules join together after a water molecule is removed from between them is an example of what?

dehydration synthesis

Water has more structure than other liquids because of its ability to form hydrogen bonds. Because of this phenomena, water expresses a relatively high __________, which allows it to cushion and protect the body's structures. *density *heat capacity *solvency *surface tension

density

A mingling of molecules and/or ions describes

dissolving

What subatomic particle carries a negative charge?

electron

What happens in oxidation-reduction (redox) reactions?

electron exchange occurs

All of the following properties are associated w/ enzymes except: *enzymes alter the chemical reaction. *enzymes are not permanently altered in the reaction. *enzymes are highly specific for individual substrates. *enzymes speed up reactions by lowering the activation energy.

enzymes alter the chemical reaction

A person who is severely dehydrated may feel hot, even if they are not in a hot environment, because:

there isn't enough surrounding water to absorb the heat produced by the body. (when dehydrated, not enough surrounding water to absorb heat, heat produced remains trapped & core temp rises)

In DNA, an adenine base will form two hydrogen bonds with

thymine base

A fatty acid that contains two or more double covalent bonds is_____. *polyunsaturated *hydrogenated *monounsaturated *saturated

polyunsaturated (Saturated has no double bonds between carbon in its chain, its carbon atoms are saturated w/ hydrogen atoms; Monounsaturated has one double bond between two carbons in chain which causes bend)

Positively charged subatomic particles are called_______.

protons

Which type(s) of subatomic particles can be located within the nucleus of an atom?

protons & neutrons

The mass number of an atom is determined by the number of:

protons + neutrons

The atomic number represents the number of ___.

protons in atom

The level of protein structure that describes how two or more polypeptides interact to assemble into a protein is the __________. *primary structure *secondary structure *tertiary structure *quaternary structure

quaternary structure (only proteins that have 2 or more polypeptides have a quaternary structure)

Energy in the human body takes on all of the following forms except: *radiant energy. *chemical energy. *electrical energy. *mechanical energy.

radiant energy

Nuclear medicine uses ___ in medical diagnosis and treatment.

radioisotopes

In a chemical equation, what are the chemicals on the left side of the arrow called?

reactants

Which of the following organic compounds is not found in the human body? *Starch *Glycogen *Cholesterol *Hemoglobin

starch

The most unsaturated fats have ... *the shortest hydrocarbon tails. *the longest hydrocarbon tails. *the highest ratio of H to C. *the most double bonds. *the fewest double bonds.

the most double bonds. (Every double bond is a place where hydrogen could be added)

Ionic bonds result from *the transfer of electrons from a metal to a nonmetal *equal sharing of electrons between nonmetals *unequal sharing of electrons between nonmetals *weak attractions between polar molecules

the transfer of electrons from a metal to a nonmetal

While looking at two equal-sized samples of pure-carbon, you discover that one of them has a greater mass than the other. This has occurred because?

there are different isotopes for carbon. (Isotopes-element has the same atomic number (protons) but a different mass number(different number of neutrons) ex. more neutrons=larger mass)