UNIT 1

Question 1

Which of these classes of biological molecules does NOT form polymers?

Answer 1

lipids

Question 2

An atom consists of 9 protons, 9 neutrons and 10 electrons.

The atom has ___ electrons in its outermost electron shell.

Answer 2

8

Question 3

The most significant role played by pH buffers is to:

Answer 3

limit major shifts in the amount of H+ and OH- in solution.

Question 4

Carbon has 4 electrons in its outermost shell and hydrogen has 1 electron in its outermost electron shell. A carbon atom can form covalent bonds with how many hydrogen atoms?

Answer 4

4

Question 5

Which of the following is a monomer?

Answer 5

Glucose

Question 6

Which functional group in nonpolar?

Answer 6

Methyl

Question 7

Carbon-14 is used to determine the age of ancient objects. If a sample is 17,190 years old and started out with 1000mg of Carbon-14, then how much Carbon-14 is remaining today? The half-life of carbon-14 is 5,730 years.

Answer 7

125 mg

Question 8

Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)?

Answer 8

Each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge.

Question 9

A friend of yours calls to say that his car would not start this morning. He asks for your help. You say that you think the battery must be dead. If so, then jump-starting the car from a good battery will solve the problem. In doing so, you are ________.

Answer 9

stating a hypothesis and using that hypothesis to make a testable prediction

Question 10

Which of the following statements about the 5’ end of RNA is correct?

Answer 10

The 5’ end has a phosphate group attached to the number 5’ carbon of ribose.

Question 11

Which molecule shown below contains a carbonyl group?

Answer 11

C. O and H group

Question 12

From these options, which is the strongest chemical bond?

Answer 12

covalent bond

Question 13

Which of the following is the strongest evidence that protein structure and function are correlated?

Answer 13

Denatured (unfolded) proteins do not function normally.

Question 14

Why does ice float in liquid water?

Answer 14

Hydrogen bonds stabilize and keep the molecules of water in ice farther apart than the water molecules of liquid water.

Question 15

An atom consists of 9 protons, 9 neutrons and 10 electrons.

This atom has a charge of:

Answer 15

-1

Question 16

What is a hypothesis?

Answer 16

a tentative explanation that can be tested and is falsifiable

Question 17

The difference between an aldose sugar and a ketose sugar is ________.

Answer 17

the position of the carbonyl group

Question 18

Testing a candidate cancer chemotherapy drug for safety before it is approved for marketing is an example of what general type of science?

Answer 18

applied

Question 19

Which of the following is the process used by the scientific community to ensure the quality of scientific research that is published?

Answer 19

peer-review

Question 20

The figure below shows the structures of glucose and fructose. These two molecules differ in the _____.

Answer 20

arrangement of carbon, hydrogen, and oxygen atoms

Question 21

Two atoms of hydrogen interact to form a(n):

Answer 21

nonpolar covalent bonds

Question 22

Which cellular process would you expect to use a hydrolysis reaction?

Answer 22

Break down of starch into glucose in muscle cells

Question 23

What is the OH- concentration of a solution with pH 3?

Answer 23

10^(-11) M

Question 24

Thalidomide and L-dopa, shown below, are examples of pharmaceutical drugs that occur as enantiomers, or molecules that _____.

Answer 24

are mirror images of one another

Question 25

What characteristic do all lipids share?

Answer 25

They are have large hydrophobic regions

Question 26

Which of the following is true of the nucleotide shown below?

Answer 26

It is a purine nucleotide found in DNA

Question 27

You disrupt all hydrogen bonds and amino acid R group interactions in a protein. What level of structure will be preserved?

Answer 27

primary structure

Question 28

Which of the following best describes the difference between starch and cellulose

Answer 28

Cellulose is a polymer of beta-glucose and forms cross-linked fibers containing many cellulose polymers that hydrogen bond. Starch is made of alpha-glucose and does not form cross-linked fibers.

Question 29

How many molecules of water are released during the synthesis of a 20 monomer-long cellulose molecule?

Answer 29

19

Question 30

Which pair of elements would likely have similar valence shells and thus similar chemical behavior?

Answer 30

nitrogen and phosphorus

Question 31

Amino acids are acids because they always possess ________ as a functional group?

Answer 31

carboxyl

Question 32

water:

Answer 32

has cohesive properties.

Question 33

Which of the following is true of unsaturated fats?

Answer 33

They have double bonds in their fatty acid chains.

Question 34

In the process of science, which of these is tested?

Answer 34

a hypothesis

Question 35

Use the following figure to answer the question. The molecule illustrated in the figure is?

Answer 35

is a cis-unsaturated fatty acid

Question 36

Which bond shown below shows a hydrogen bond that is possible?

Answer 36

i

Question 37

What component of amino acid structure varies among different amino acids?

Answer 37

the components of the R group

Question 38

About 25 of the 92 natural elements are known to be essential to life. Which 4 of these 25 elements make up approximately 96% of living matter?

Answer 38

carbon, hydrogen, nitrogen, oxygen

Question 39

The two molecules shown in the figures are best described as ________

Answer 39

structural isomers

Question 40

Which of these is an example of inductive reasoning?

Answer 40

Hundreds of individuals of a species have been observed and all are photosynthetic; therefore, the species is photosynthetic.