AP Biology Exam #1

If an atom (atomic number 16) were allowed to react with atoms of hydrogen (atomic number 1), the atoms will form together in fixed ways into molecules following the valence electron configures of the two atoms. Which of the molecules below would be the most likely result? a.)S - H b.) H - S - H c.) H - S - H | H d.) H | H - S - H | H

B.) H - S - H

Identical heat lamps are arranged to shine on identical containers of water and methanol (wood alcohol), so that each liquid absorbs the same amount of energy minute by minute. The covalent bonds of methanol molecules are nonpolar, so there are no hydrogen bonds among methanol molecules. Which of the following graphs correctly describes what will happen to the temperature of the water and the methanol? Graph a.) b.) c.) d.)

Graph A

Which two functional groups are always found in amino acids regardless of which of the 20 amino acids are considered? a.) carboxyl and amino b.) carbonyl and amino c.) carboxyl and aldehyde d.) phosphate and sulfhydryl

a.) Carboxyl and amino

Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is a change of some sort within the atom. Which of the following would be a correct example of a possible change due to the absorption of energy? a.) an electron may move to an electron shell farther out from the nucleus b.) an electron mopy move to an electron shell closer to the nucleus c.) the atom would likely lose a neutron and become a radioactive isotope d.) the atoms would likely lose the electron all together and become a negatively charged ion, or anion

a.) an electron may move to an electron shell farther out from the nucleus

What is the term used for a protein molecule complex found in cells that assists in the proper folding of other proteins when they have been damaged by by excessive heat and pH? a.) chaperon protein b.) tertiary protein c.) enzyme protein d.) renaturing protein

a.) chaperon protein

Nitrogen (N) has an electronegativity value of 3.0 while the electronegativity value of hydrogen (H) is 2.2. differences of electronegativity greater than 0.5 tend to result in charged or polar molecules while values less than 0.5 tend to to result in non-polar molecules. Which of the following statements is correct about the atoms in ammonia (NH3)? a.) each hydrogen atom has a partial positive charge b.) the nitrogen atoms has a strong positive charge c.) each hydrogen atoms has a slight negative charge d.) the nitrogen atom has a partial positive charge

a.) each hydrogen atom has a partial positive charge

Choose the term that correctly describes the relationship between these two sugar molecules: a.) structural isomers b.) geometric isomers c.) enantiomers d.) isotopes

a.) structural isomers

Water has a high specific heat that allows a body of water to absorb a great deal of energy from the sun during the day and slowly release the heat into the air at night. This property of water allows the climate of nearby areas to be moderated from extreme changes. This of water is caused by: a.) the absorption and release of heat when hydrogen bonds break and form between different molecules of water b.) the high specific heat of oxygen and hydrogen atoms that make up a water molecule c.) the small size of the water molecules which allows them to vibrate very rapidly. d.) the fact that water is a poor heat conductor so it takes a much longer time for the heat to be transferred

a.) the absorption and release of heat when hydrogen bonds break and form between different molecules of water

Elements used in organisms can be classified in a number of ways. If the term ¨trace element¨ is applied to a particular element, the modifier "trace" means: a.) the element can be used as a radioactive isotope label to "trace" atoms through an organism's metabolism b.) the elements can be used as a radioactive isotope lebel to "trace" atoms through an organismś metabolism. c.) the element is very rare on Earth and is likely very valuable as it only exists in "traces" in the earth's crust d.) the element enhances health but is not essential for the organism's long-term survival

a.) the element can be used as a radioactive isotope label to "trace" atoms through an organism's metabolism

Functional groups are very important to the chemistry of the carbon skeletons they are attracted to. Sometimes these functional can be modified into other functional groups. Which actions would produce a carbonyl group on a molecule? a.) the replacement of the -OH of a carboxyl group with hydrogen b.) the addition of a thiol to a hydroxyl c.) the addition of a hydroxyl to a phosphate d.) the replacement of the nitrogen of an amine with oxygen

a.) the replacement of the -OH of a carboxyl group with hydrogen

The following question is based on a figure of : A solute molecule surrounded by a hydration shell of water... Based on your knowledge of the polarity of water molecules, the solute molecule is most likely to have what property? a.) the solute is positively charged b.) the solute is negatively charged c.) the solute is without charge. The water molecules are just reacting to each other d.) the solute is hydrophobic and the water molecules are being equally repelled

a.) the solute is positively charged

Evolution is biologyś cor theme that ties together all the other Big Ideas. This is because evolution explains: a.) the unity and diversity of life b.) how organisms become adapted to their environment through the mutation of varying individuals c.) why distantly related organisms never resemble each other d.) explains why no organisms have traits in common

a.) the unity and diversity of life

Based on the electron configuration diagrams below, which if the following pairs of atoms would be most likely to form an ionic bond? a.) b.) c.) d.) e.)

b.)

The reactivity of an atom in forming chemical bonds with other atoms and elements arises from what property of the atom? a.) the average distance of the outermost electron shell from the nucleus. b.) The existence of unpaired electrons in the valence shell c.) the sum of the potential energies of all the electron shells d.) the potential energy of the valence shell electrons

b.) The existence of unpaired electrons in the valence shell

The slight negative charge at one end of one water molecule is attracted to the slight positive charge of another water molecule. What is this attraction called? a.) a covalent bond b.) a hydrogen bond c.) an ionic bond d.) a hydrophilic bond

b.) a hydrogen bond

The R group or side chain of the amino acid serine is -CH2-OH. The R group or side chain of the amino acid alanine is -CH3. Where you expect to find these amino acids in a globular protein in aqueous solution? a.) serine would be in the interior, and alanine would be on the exterior of the globular protein b.) alanine would be in the interior, and serine would be on the exterior of the globular protein c.) both serine and alanine would be in the interior of the globular protein d.) both serine and alanine would be on the exterior on th exterior of the globular protein

b.) alanine would be in the interior, and serine would be on the exterior of the globular protein

Similarity in protein structure often indicates relatedness between organisms. Image that a new organism is discovered in the forest of Cost Rica. Scientists determine that the polypeptide sequence of hemoglobin from new organism has 72 amino acid differences from human, 65 differences from a gibbon, 49 differences from a rat, and 5 differences from a frog. The data suggests that the new organism: a.) is more closely related to humans than to frogs b.) is more closely related to frogs than to human c.) may have evolved from gibbons but not rats d.) is more closely related to human then to rats

b.) is more closely related to frogs than to humans

What is the pH of a solution that has a hydroxyl ion [OH-] concentration of 10^-10 M? a.) pH 2 b.) pH 4 c.) pH 10 d.) pH 12

b.) pH 4

A controlled experiment is the goal of a science researcher and must be carefully planned. One of the characteristics of a controlled experiment is that it has which of the following? a.) it proceeds slowly enough that a scientist can make careful records of the results and record them in their Excel Spreadsheet b.) the experiment may include several experimental groups, but it also has a control group that is different from the experimental groups by a single variable c.) is repeated many times to make sure the results are accurate d.) it has a dependent variable that occurs with regular intervals on the graph axis

b.) the experiment may include several experimental groups, but it also has a control group that is different from the experimental groups by a single variable

The molecular formula for glucose is C6H16O6. What would be the molecular formula for a polymer made by linking teen glucose molecules together by dehydration reactions? a.) C60H120O60 b.) C6H12O6 c.) C60H102O51 d.)C60H100O50

c.) C60H102O51

The formation of macromolecules from monomers uses a common chemical reaction in all macromolecule classes. What is the chemical mechanism by which cells make polymers from monomers? a.) phosphodiester linkages b.) hydrolysis c.) dehydration synthesis d.) deconstruction reactions

c.) Dehydration Synthesis

You have two beakers. One contains pure water, the other contains pure methanol (wood alcohol). The covalent bonds of methanol molecules are nonpolar, so there are no hydrogen bonds among methanol molecules. You pour crystals of table salt (NaCl) into each beaker. Predict what will happen. a.) Equal amounts of NaCl crystals will dissolve in both water and methanol b.) NaCl crystals will not dissolve in either water or methanol c.) NaCl crystals will dissolve readily in water but will not dissolve in methanol d.) NaCl crystals will dissolve readily in methanol but will not dissolve in water

c.) NaCl crystals will dissolve readily in water but will not dissolve in methanol

A group of molecular biologists is trying to synthesize a new artificial compound to mimic the effects of a known hormone that influences sexual behavior. They have turned to you for advice. Which of the following compounds is most likely to mimic the effects of the hormone? a.) a compound with the same number of carbon, hydrogen and oxygen atoms as the hormone b.) a compound with the same molecular mass (measured in daltons) as the hormone c.) a compound with atoms arranged in the same three-dimensional shape as part of hormone d.) a compounds with atoms arranged in the same number of double bonded Carbons as the hormone

c.) a compound with atoms arranged in the same three-dimensional shape as part of hormone

Each element is unique and different from other elements because of number of protons in the nuclei of its atoms. which of the following is the term indicates the number of protons in an atom's nucleus of its atoms. Which of the following is the term that indicates the number of protons in an atom's nucleus ? a.) atomic mass b.) atomic weight c.) atomic number d.) mass weight

c.) atomic number

Testosterone and estradiol are male and female sex hormones respectively in many vertebrates. In what way(s) do these molecules differ from each other? a.) testosterone and estradiol are structural isomers but have the same molecular formula b.)testosterone and estradiol are geometric isomers burt have the same molecular formula c.) testosterone and estriol have different functional groups attached to the same carbon skeleton d.) testosterone and estradiol have distinctly different chemical structures, with one including four fused rings of carbon atoms, while the other has three rings

c.) testosterone and estriol have different functional groups attached to the same carbon skeleton

Pure, freshly-distilled water has a pH of 7. This means that: a.) there are no H+ ions in the water so the water is neutral. b.) there are no OH- ions in the water so the water is neutral. c.) the concentration of H+ ion in the water equals the concentration of OH- ions in water. d.) the concentration of H+ ions in the water is 7 times the concentration of OH- ions in the water.

c.) the concentration of H+ ion in the water equals the concentration of OH- ions in water.

Which of the following best describes the relationship between the atoms described below? Atom 1 Atom 2 31p 32p 15 15 a.) they are both phosphorus cations b.) they are both phosphorus anions c.) they are both isotopes of phosphorus d.) they are both isomer of phosphorus

c.) they are both isotopes of phosphorus

The difference between the pentose sugar in DNA and the pentose sugar in RNA is that the sugar in DNA: a.) is a six sided ring in DNA and the sugar in RNA is a five sided ring b.) can form a double-stranded molecule c.) has a six-membered ring of carbon and nitrogen atoms d.) contains one less oxygen atom on the No. 2

d. ) contains one less oxygen atom on the No. 2

Life is characterized by a series of common properties. Which of the following is a property associated with life? a.) evolution by an individual b.) energy processing by creating energy from matter c.) adapting to the environment d.) Growth by internal changes

d.) Growth by internal changes

Why does solid water, or ice, float in liquid water? a.) The liquid water molecules have more kinetic energy and thus support the ice b.) The hydrogen bonds between the molecules in ice prevent the ice from sinking c.) Ice always has air bubbles trapped in the structure that act as little like preservers and keep it afloat d.) Hydrogen bonds stabilize and keepo the molecules of water ice farther apart than the molecules of liquid water liquid. This changes the density of ice allowing the ice to float

d.) Hydrogen bonds stabilize and keepo the molecules of water ice farther apart than the molecules of liquid water liquid. This changes the density of ice allowing the ice to float

Which of the following statements is true about a solutions that is buffered? a.) They maintain a constant pH when bases are added to them but not when acids are added to them b.) They maintain a constant pH when acids are added to them but not when bases are added to them c.) They maintain a constant pH of exactly 7 in all living cells and biological fluids d.) They maintain a relatively constant pH when either acids or bases are added to them. They have the capacity to release and absorb H+ ions.

d.) They maintain a relatively constant pH when either acids or bases are added to them. They have the capacity to release and absorb H+ ions.

The structure depicted in the above diagram shows the: a.) 1-4 linkage of the a glucose monomers of starch b.) 1-4 linkage of the B glucose monomers of cellulose. c.)double helical structure of a DNA molecule d.) a helix secondary structure of a polypeptide

d.) a helix secondary structure of a polypeptide

Lactoase, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose best classified as a macromolecule type? a.) as a pentose b.) as a hexose c.) as a monosaccharide d.) as a disaccharide

d.) as a disaccharide

Charles Darwin proposed a mechanism for descent with modifications which stated that organisms of a particular species were successful in the event of Evolution if certain criteria were achieved. What are those criteria for success? a.) non-inheritable traits that enhance their survival in the local environment b.) non-inheritable traits that enhance their reproductive success in the local environment c.) non-inheritable traits that enhance their survival and reproductive success in the local environment d.) inheritable traits that enhance their survival and the ability to be productive successful in the local environment

d.) inheritable traits that enhance their survival and the ability to be productive successful in the local environment

Cellulose is one of the most common polymers on planet Earth. Which of the following is true statement regarding cellulose? a.) it is a polymer composed of sucrose monomer b.) it is a storage polysaccharide for energy in plant cells c.) it is a storage polysaccharide for energy in animal cells d.) it is a structural polysaccharide of plant cell walls

d.) it is a structural polysaccharide of plant cell walls

Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature? a.) water's lowing of density when it condensed into ice and the hydrogen bonds push the individual water molecules further apart b.) water's ability to dissolve other polar molecules. Water is the universal solvent. c.) the release of hear by the formation of hydrogen bonds when water evaporates d.) the absorption of heat from a material by the breaking of hydrogen bonds when water changes from a liquid into a gas.

d.) the absorption of heat from a material by the breaking of hydrogen bonds when water changes from a liquid into a gas.

Which of the following is an example of hydrolysis chemical reaction? a.) the reaction of two monosaccharides, forming a disaccharide with the release of water b.) the synthesis of two amino acids, forming a peptide with the release of water c.) the reaction of a fat, forming glycerol and three fatty acids with the utilization of water d.) the reduction of a fat, forming glycerol and three fatty acids with the utilization of water

d.) the reduction of a fat, forming glycerol and three fatty acids with the utilization of water