chapter 2 chemistry of life

Question 1

Chemistry is the scientific study of

Answer 1

substances, especially the interaction of substances.

Question 2

Anything that has weight and occupies space is

Answer 2

matter

Question 3

All matter is composed of

Answer 3

chemical elements, substances that cannot be broken down by

Question 4

Carbon,hydrogen are examples of

Answer 4

chemical elements.

Question 5

Atom

Answer 5

is the functional unit of an element. It consists of the nucleus, which contains protons, neutrons, and surrounding elements.

Question 6

Molecule,

Answer 6

two or more atoms are joined to form an element.For example—O2

Question 7

Element

Answer 7

s a substance composed of only one type of atom that cannot be broken into simpler ingredients by chemical means.For example –Oxygen,hydrogen

Question 8

Compound

Answer 8

is a chemical combination of two or more elements. For example NaCl

Question 9

An atom is the smallest

Answer 9

unit of element that participates in chemical reactions.

Question 10

Atoms are composed of three types of subatomic particles,

Answer 10

protons, neutrons and electrons.

Question 11

Each proton has a _____ electrical charge.

Answer 11

positive

Question 12

Each electron has a _____ electrical charge.

Answer 12

negative

Question 13

Each neutron has ___ electrical charge.

Answer 13

no

Question 14

Protons and neutrons are located in the

Answer 14

centrally located nucleus of an atom.

Question 15

Electrons rotate at high speed around

Answer 15

the nucleus.

Question 16

The atom of each element are characterized by specific

Answer 16

atomic number, symbol and atomic weight.

Question 17

The number of protons in the nucleus is an atom’s

Answer 17

atomic number.

Question 18

The number of protons and neutrons combined is the atom’s

Answer 18

atomic mass

Question 19

An atom of an element with different number of neutrons is called as an

Answer 19

isotope

Question 20

electrons keep darting about within certain limits called

Answer 20

orbitals

Question 21

Orbitals are arranged into

Answer 21

energy level(shells)

Question 22

The farther an orbital extends from the nucleus,

Answer 22

the higher its energy level is.

Question 23

The number of electrons in the outer energy level of an atom determines how it behaves chemically This behavioris called as

Answer 23

chemical bonding.

Question 24

Most chemicals in the body are in the form of

Answer 24

molecules

Question 25

Chemical formula

Answer 25

determines atoms present in a compound.

Question 26

Types of Chemical Bonds

Answer 26

Ionic Bonds•Covalent Bonds

Question 27

Radioactive isotope:

Answer 27

Isotope that emits radiation

Question 28

Covalent bonds

Answer 28

Covalent bonds form when atoms share their outer energy to fill up and thusbecome stable

Question 29

Hydrogen bonds

Answer 29

A kind of weak attraction that helps hold your body’s substance together

Question 30

Examples of inorganic molecules:

Answer 30

water ,acids, bases, and salts.

Question 31

When water is the solvent for a mixture (a blend of two or more kinds of molecules), the mixture is called an

Answer 31

aqueous solution.

Question 32

Dehydration synthesis:

Answer 32

Chemical reaction in which water is removed from small molecules and then strung together to form a larger molecule

Question 33

Hydrolysis:

Answer 33

Chemical reaction in which water is added to the subunits of a large molecule to break it apart into smaller molecules

Question 34

pH:

Answer 34

is a measure of how acidic or basic a solution is

Question 35

Neutralization:

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Acids and bases mix to form salts

Question 36

Buffers:

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Chemical systems that absorb excess acids or bases and thus maintain a relatively stable pH

Question 37

The basic unit of carbohydrate molecules is called a

Answer 37

monosaccharide.

Question 38

Lipids are

Answer 38

fats and oils.

Question 39

Triglycerides

Answer 39

Made up of one glycerol unit and three fatty acids–Store energy for later use

Question 40

Phospholipids

Answer 40

with only two fatty acids, and with a phosphorus-containing group attached to glycerol

Question 41

Cholesterol

Answer 41

is a steroid lipid. It helps making the steroid hormones.Copyright © 2016 by Elsevier Inc. All

Question 42

Proteins

Answer 42

very large molecules made up of amino acids

Question 43

Nucleic acids

Answer 43

Made up of nucleotide units,

Question 44

Deoxyribonucleic acid (DNA)

Answer 44

Used as the cell’s “master code” for assembling proteins

Question 45

Ribonucleic acid (RNA)

Answer 45

Used as a temporary “working copy” of a gene (portion of the DNA code)