Deck 2: Chemistry of Life

Question 1

Carbon dating is a common method employed in dating certain kinds of fossils.It is based upon the radioactive decay of an isotope of carbon (C¹⁴).Referring to the atomic number of carbon attained from figure 2.1,how many neutrons does C¹⁴ have?

A) 2
B) 4
C) 8
D) 12
E) 14

Answer 1

C
Explanation: Carbon fourteen possesses two more neutrons than carbon twelve, for a total of 8 neutrons.

Question 2

In an atom,the number of protons always equals the number

A) of electrons.
B) of neutrons.
C) of neutron and protons.
D) of quarks.
E) of neutrinos.

Answer 2

A
Explanation: In an atom, the number of protons always equals the number of electrons.

Question 3

Atoms that share electrons have what type of bonds?

A) covalent
B) neutral
C) hydrogen
D) colloidal
E) ionic

Answer 3

A
Explanation: Atoms that share electrons have covalent bonds.

Question 4

Be has an atomic number of 4 and an atomic mass of 9.How many protons does it have?

A) 4
B) 5
C) 9
D) 13

Question 5

Hydrogen bonds

A) result from the loss of neutrons by an atom.
B) result in the formation of salts.
C) involve the loss and gain of electrons.
D) involve the sharing of electrons.
E) are relatively weak and can be broken rather easily.

Question 6

How many elements occur naturally?

A) 112
B) 92
C) 64
D) 32
E) 6

Question 7

CaCl₂ is a salt that forms as the result of what type of bond?

A) covalent
B) hydrogen
C) polar
D) non-polar
E) ionic

Question 8

The smallest unit of an element that still retains the chemical and physical properties of that element is called

A) an isotope.
B) a nucleus.
C) an atom.
D) a molecular bond.
E) a neutrino.

Question 9

Water makes up 60-70% of total body weight.

Question 10

The atomic number of an atom is determined by the number of

A) protons.
B) neutrons.
C) electrons.
D) protons and neutrons.
E) protons and electrons.

Question 11

What is the symbol for sodium?

A) Na
B) S
C) So
D) N
E) Dm

Question 12

Examine the section of the periodic table in Figure 2.1.Which element will behave similarly to C?

A) Ca
B) S
C) Ar
D) Si
E) Mg

Question 13

An element has its outermost orbital full and contains more than 2 electrons.Which element is this?

A) He
B) Ne
C) C
D) N
E) O

Question 14

An element cannot be broken down by chemical means.

Question 15

Isotopes of an element differ due to the number of

A) protons.
B) neutrons.
C) electrons.
D) both protons and electrons.
E) neutrinos.

Question 16

What is iodine 131,used in medicine to produce various images of organs and tissues,called?

A) A mixture
B) A tracer
C) An emulsion
D) A colloid
E) A sensor

Question 17

Ca₃(PO₄)₂ represents a/an

A) element.
B) mixture.
C) compound.
D) isotope.
E) atom.

Question 18

Why is He over Ne in the periodic table? (Refer to Figure 2.1)

A) They both have the same atomic mass.
B) They both have the same number of electrons in their outermost orbital.
C) They both have a full outermost orbital.
D) They both have the same atomic number.
E) They both have the same number of protons in their nuclei.

Question 19

Radiation can produce both positive and negative effects for humans.

Question 20

A combination of two or more atoms of the same type is called

A) an atomic unit.
B) a molecule.
C) a compound.
D) an isotope.
E) an ion.

Question 21

Which of the following is not one of the four classes of organic molecules found in cells?

A) vitamins
B) lipids
C) proteins
D) carbohydrates
E) nucleic acids

Question 22

A solution containing 0.00001 moles of H⁺ has a pH of

A) 3
B) 5
C) 7
D) 9
E) 11

Question 23

The main function of carbohydrates is for long-term energy storage.

Question 24

Our body is capable of converting starch into glycogen.

Question 25

The presence of a buffer in our blood is an example of homeostasis.

Question 26

William noticed blood mysteriously climbing up a capillary tube.This is an example of which property of water?

A) Frozen water is less dense than liquid water.
B) The temperature of liquid water rises and falls slowly.
C) Water molecules are cohesive.
D) Water has a high heat of vaporization.
E) Water is a solvent.

Question 27

Joining small molecules (monomers)together to form longer chains (polymers)requires a process called

A) a hydrolysis reaction.
B) a dehydration reaction.
C) monomerization.
D) emulsification.
E) disassembly.

Question 28

NaCl is not an organic molecule.

Question 29

Which polysaccharide is branched the most?

A) cellulose
B) starch
C) glycogen

Question 30

Which of the following characteristics of water is most responsible for the sinking of the Titanic?

A) Water is liquid at room temperature.
B) Water has a high heat of vaporization.
C) The temperature of liquid water rises and falls slowly.
D) Frozen water is less dense than liquid water.
E) Water molecules are cohesive.

Question 31

On a warm day in April,Tina jumped into the swimming pool.To her surprise the water was really cold.Which property of water did she discover?

A) Water molecules are cohesive.
B) The temperature of liquid water rises and falls slowly.
C) Water possesses hydrogen bonds.
D) Water is a polar molecule.
E) Frozen water is less dense than liquid water.

Question 32

What passes through the digestive tract as fiber or roughage?

A) Chitin
B) Glucose
C) Glycogen
D) Starch
E) Cellulose

Question 33

The reason water is polar is because

A) in polar molecules atoms share electrons evenly.
B) the oxygen atom is larger than the hydrogen atom.
C) hydrophilic molecules interact with water.
D) hydrophobic molecules do not interact with water.
E) there is a transfer of electrons from the hydrogen to the oxygen.

Question 34

Starch,cellulose,and glycogen are alike in that

A) they are all made of glucose.
B) they contain the same number of side chains.
C) they have the same types of bonds between the monomer units.
D) they are all found in animals.
E) they can all be digested by our bodies.

Question 35

In an acidic solution

A) the number of H⁺ is less than the number of OH^-.
B) the number of H⁺ is greater than the number of OH^-.
C) the number of H⁺ is equal to the number of OH^-.

Question 36

Which of the following is not a monosaccharide?

A) glucose
B) fructose
C) galactose
D) maltose

Question 37

Sugars with three to seven carbon atoms are called

A) monosaccharides.
B) disaccharides.
C) trisaccharides.
D) polysaccharides.
E) steroids.

Question 38

A solution with a pH of 7 has 10 times as many H⁺ as a pH of 6.

Question 39

A hydrolysis reaction involves the loss of water.

Question 40

A fat contains how many fatty acids?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 41

Fats are usually of animal origin while oils are usually of plant origin.

Question 42

All amino acids are alike in that their R groups are polar.

Question 43

The membranes of cells are composed of

A) phospholipids.
B) fats.
C) oils.
D) steroids.
E) triglycerides.

Question 44

Which of the following is not a function of proteins?

A) quick energy
B) support
C) transport
D) enzymes
E) motion

Question 45

ATP carries energy in the form of high-energy

A) carbohydrate bonds.
B) peptide bonds.
C) lipid bonds.
D) phosphate bonds.
E) hydrogen bonds

Question 46

Which of the following is not present in a nucleotide?

A) phosphate
B) nitrogenous base
C) 5 ring sugar
D) an R group
E) a pentose

Question 47

A species has 29% of its DNA composed of the nucleotide containing guanine (G).What percent does the nitrogen base thymine (T)equal?

A) 58%
B) 42%
C) 21%
D) 67%
E) 29%

Question 48

Fats and oils function well as energy-storage molecules because they contain carbon.

Question 49

A fatty acid that contains only single bonds between the carbon atoms is considered

A) saturated.
B) unsaturated.
C) trans unsaturated.

Question 50

How are fats,phospholipids,and steroids alike?

A) They are all solid at room temperature.
B) They each contain a polar phosphate group.
C) They each contain only 1 fatty acid.
D) They do not dissolve in water.
E) They all contain at least one carbon ring.

Question 51

An alpha helix or a beta sheet are examples of what level of protein structure?

A) secondary
B) primary
C) tertiary
D) quaternary

Question 52

ATP is called the energy currency of the body because it is a type of electricity.

Question 53

When an ATP molecule is used to supply energy,which of the following occurs?

A) a phosphate bond is added
B) a phosphate bond is broken
C) oxygen is removed
D) oxygen is added
E) an adenine is added

Question 54

When two amino acids combine via a dehydration reaction,

A) a peptide bond is formed.
B) the R groups are lost.
C) water is added to begin the reaction.
D) the carboxyl group of each join together.
E) the amino group of each join together.

Question 55

The sex hormones belong to which category of lipids?

A) steroids
B) fats
C) oils
D) triglycerides
E) phospholipids

Question 56

The sides of the DNA ladder (backbone)are

A) alternating carbons and nitrogens.
B) the R groups.
C) the nitrogenous bases.
D) alternating nitrogens and phosphates.
E) sugars and phosphates.

Question 57

Which of the following nitrogenous bases is NOT found in DNA?

A) cytosine
B) thymine
C) uracil
D) guanine
E) adenine

Question 58

The function of RNA in the body is to store the genetic information in the nucleus.

Question 59

The monomer unit of a protein is

A) fatty acids.
B) amino acids.
C) monosaccharides.
D) polysaccharides.
E) nucleic acids.

Question 60

What makes each amino acid unique?

A) the central carbon
B) the R group
C) the amino group
D) the carboxyl group