Unit 2 Exam (Chapters 5 and 27) Flashcards Preview

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Flashcards in Unit 2 Exam (Chapters 5 and 27) Deck (210):
1

All living things are made up of four classes of large biological molecules. Those four are

carbohydrates, lipids, proteins, and nucleic acids

2

Within cells, small organic molecules are joined together to form

larger molecules

3

Macromolecules

are large molecules composed of thousands of covalently connected atoms.
Carbohydrates, lipids, proteins, and nucleic acids.

4

Molecular structure and function are

inseparable

5

A polymer

is a long molecule consisting of many similar building blocks.
Ex. like 4 expo markers being put together and connected at each end making a long stick.

6

Monomers

are the small building-block molecules that combine and form polymers.
Ex. one expo marker

7

Three of the four classes of life's organic molecules are polymers. These three are

Carbohydrates
Proteins
Nucleic Acids

8

A dehydration reaction

occurs when two monomers bond together through the loss/production of a water molecule.
-Building up.
Removing water causes things to build up and stick together.

9

Polymers are disassembled to monomers by

hydrolysis

10

Hydrolysis

a reaction that is essentially the reverse of the dehydration reaction.
-Breaking apart.
Adding water causes it to break a part. The breaking apart happens after you add a water molecule.

11

Each cell has thousands of different

macromolecules

12

Macromolecules vary among cells of an organism, vary more within a species, and

vary even more between species

13

An immense variety of polymers can be built from a small set of

monomers.
This is because of arrangement. Its like the alphabet and the 26 letters that create millions of different words.

14

Carbohydrates

include sugers and the polymers of sugars.

15

The simplest carbohydrates are

monosaccharides, or single sugars.

16

Disaccharides are

two monosaccharides

17

Carbohydrate macromolecules are

polysaccharides

18

Polysaccharides are

polymers composed of many sugar building blocks

19

Three Carbohydrates

-Monosaccharides
-Disaccharides
-Polysaccharides

20

Sugars- Names end in

-ose

21

Monosaccharides

have molecular formulas that are usually multiples of CH2O

C and O will always have the same amount.
H is always double of what C and O are.

CH2O
1:2:1

C6H12O6
1:2:1

22

Glucose (C6H12O6) is

the most common monosaccharide.
-Vary in length, location of carbonyl, isomers

23

Monosaccharides Structure

CH2O
1:2:1

24

Monosaccharides are the

simplest

25

Monosaccharides Function

-Major fuel for cells (food, energy)
-Raw material for building molecules (use them as bricks to make other molecules)

26

Though often Monosaccharides are drawn as linear skeletons,

aqueous solutions many sugars form rings.
When wet, they will form rings.
When dry, they form straight lines.

27

Two monosaccharides=

a disaccharide

28

A disaccharide is

formed when a dehydration reactions joins two monosaccharides

29

The covalent bond that joins two monosaccharides and forms a disaccharide is called a

glycosidic linkage

30

Disaccaride function

do not need to know or worry about!

31

Three Disaccaride structures

Glucose + Fructose = Sucrose
Glucose + Glucose = Maltose
Glucose + Galactose = Lactose

32

Glucose + Fructose =

Sucrose

33

Glucose + Glucose =

Maltose

34

Glucose + Galactose =

Lactose

35

Dehydration reaction in the synthesis of

Maltose
(and in the synthesis of Sucrose as well)

36

Polysaccharides

the polymers of sugars
they have storage and structural roles

37

Polysaccharides structure and function are determined by its

sugar monomers and the positions of glycosidic linkages

38

Storage Polysaccharide
Starch

Starch, a polysaccharide of plants, consists entirely of glucose monomers.
lots of glucose.

39

Starch structure

1-4 a(alpha) linkages
a helical shape.

Plants make starch made up of a alpha glucose

40

Starch Function

Storage.
Plants store surplus starch as granules within chloroplasts and other plastids

41

Amylose

a simple starch.
unbranched

42

Amylopectin

a complex starch.
a few branch points.

ex. brown rice, whole grains

43

Starch structure and function

structure- plants-- alpha glucose
function- storage

44

Storage Polysaccharide
Glycogen

is a polysaccharide in animals.

45

Glycogen structure

all glucose monomers.
highly branched.

46

Glycogen Function

Storage
Humans and other vertebrates store glycogen mainly in liver and muscle cells.
Stores only last 24 hours.
(how we store our energy)

47

Glycogen structure and function

structure- animals- glucose
function- storage

48

Structural Polysaccharide
Cellulose

The polysaccharide cellulose is a major component of the tough wall of plant cells.
made up of hundreds of glucose that only plants make.

49

Cellulose structure

like starch, cellulose is a polymer of glucose, but the glycosidic linkages differ.
The difference is based on two ring forms for glucose: alpha (a) and beta (B).
They look a little different.

50

a (alpha) glucose

is starch

51

B (beta) glucose

is cellulose

52

Cellulose Structure and Function

structure- plants- B (beta) glucose
Function- structure- it makes cell walls

53

polymers with a (alpha) glucose are

helical shapes
(Starches)

54

polymers with B (beta) glucose are

straight
(cellulose).

55

In straight structures of polymers/polysaccharides

H atoms on one strand can bond with OH groups on other strands (hydrogen bonds).
Parallel cellulose molecules held together this way are grouped into microfibris which form strong building materials for plants.

56

Enzymes that digest starch by hydrolyzing a (alpha) linkages can't

hydrolyze B (beta) linkages in cellulose

57

Cellulose in human food passes through the

digestive tract as insoluble fiber

58

Some microbes use

enzymes to digest cellulose

59

Many herbivores, from cows to termites, have

symbiotic relationships with those microbes that use enzymes to digest cellulose.

60

We can not digest

B (beta) linkages

61

Structural Polysaccharide
Chitin

Chitin, another structural polysaccharide, is found in the exoskeleton of anthropods.
(the crunch sound when you step on bugs?)

62

Chitin also provides

structural support for the cell walls of many fungi

63

Chitin function

structure

64

Chitin structure

don't worry about? see picture on slide?

65

Lipids are

the one class of large biological molecules that do NOT form polymers

66

The unifying feature of lipids is having

little or no affinity for water.
None of lipids like water.

67

Lipids are hydrophobic because

they consist mostly of hydrocarbons, which form nonpolar covalent bonds

68

Most biologically important lipids

fats
phospholipids
steroids

69

Lipids do not have any

monomers

70

Lipids bond is called an

ester linkage bond

71

Fats

are constructed from two types of smaller molecules: glycerol and fatty acids

72

Glycerol is a

three-carbon alcohol with a hydroxyl group attached to each carbon

73

A fatty acid consists of

a carboxyl group attached to a long carbon skeleton

74

Fats separate from water because

water molecules form hydrogen bonds with each other and exclude the fats

75

Fats structure

in a fat, three fatty acids are joined to a glycerol by an ester linkage, creating a triacylglycerol or triglyceride.

76

ester linkage bond is like a

covalent bond

77

Bond between glycerol and 3 fatty acids is called an

ester linkage

78

Fatty acids vary in length (number of carbons) and in the number and

locations of double bonds
(not al the same)

79

Saturated Fatty acids

have the maximum number of hydrogen atoms possible and no double bonds

80

Unsaturated fatty acids

have one or more double bonds (cis)

81

Saturated fat

all single bonds.
straight ones.
Solid at room temperature.
Bad for you.
They are packed together densely

82

Unsaturated fat

double bond in it somewhere which creates a kink.
liquid at room temperature.
you want to eat these.
they are good for you.
healthiest.

83

Fats made from saturated fatty acids are called

saturated fats, and are solid at room temperature.
Most animal fats are saturated

84

Fats made from unsaturated fatty acids are called

unsaturated fats or oils, and are liquid at room temperature.
Plant fats and fish fats are usually unsaturated

85

A diet rich in saturated fats contributes to

cardiovascular disease through plague deposits

86

Hydrogenation is

the process of converting unsaturated fats to saturated fats by adding hydrogen

87

Hydrogenating vegetable oils also creates unsaturated fats with

trans double bonds

88

These Trans fats may contribute more than

saturated fats to cardiovascular disease.
the body has no way of processing these.
really bad for us.
death if eat them

89

Certain unsaturated fatty acids are not

synthesized in the human body.
these must be supplied in the diet.

these essential fatty acids include the omega-3 fatty acids, required for normal growth, and thought to provide protection against cardiovascular disease.
(fish oils is where we get them)

90

Fats function

the major function of fats is energy storage.

91

Humans and other mammals store their fat in

adipose cells.

92

Adipose tissue also cushions

vital organs and insulates the body

93

Fats structure and function

structure- glycerol + 3 fatty acids [saturated, unsaturated, trans fat]
function- energy storage, cushion organs

94

Phospholipids structure

phospholipid is made up of
glycerol
two fatty acids
a phosphate group.

95

In a phospholipid, the two fatty acid tails are

hydrophobic, but the phosphate group and its attachments form a hydrophilic head

96

When phospholipids are added to water, they self-assemble into a bilayer, with the hydrophobic tails

pointing toward the interior.

this is important because it relates to the function.

97

The structure of phospholipids results in

a bilayer arrangement found in cell membranes.

98

all cell membranes are made up of

phospholipids

99

Phospholipids function

phospholipids are the major component of all cell membranes

100

Phospholipids structure and function

structure- a glycerol, 2 fatty acids, and a phosphate group
function- cell membranes

101

Steroids structure

steroids are lipids characterized by a carbon skeleton consisting of four fused rings

102

Steroids function

cholesterol, an important steroid, is a component in animal cell membranes.
Many hormones (Estrogen, testosterone) are synthesized from cholesterol. (steroids).

103

Although cholesterol is essential in animals,

high levels in blood contribute to cardiovascular disease.

104

Need cholesterol so we can

build cell membranes and have steroids (estrogen, testosterone)

105

Steroids structure and function

structure- four fused rings
function- cell membranes/hormones

106

Proteins account for more than

50% of the dry mass of most cells.
(This is important!!!)

107

Proteins have 8 functions

1. Enzymatic
2. Defense against foreign substances
3. Storage
4. Transport
5. Hormonal
6. Receptor
7. Contractile/movement
8. Structural

108

Proteins can do a

wide variety of jobs

109

Enzymatic proteins

speed up reactions.
Function- selective acceleration of chemical reactions.
example: digestive enzymes catalyze the hydrolysis of bonds in food molecules

110

Defensive proteins

function- protect against disease
example: antibodies inactivate and help destroy viruses and bacteria

111

Storage proteins

function- storage of amino acids
example: casein, the protein of milk, is the major source of amino acids for baby mammals. Plants have storage proteins in their seeds. Ovalbumin is the protein of egg white, used as an amino acid source for the developing embryo

112

Transport proteins

function- transport of substances
examples: hemoglobin, the iron-containing protein of vertebrate blood, transports oxygen from the lungs to other parts of the body. other proteins transport molecules across cell membranes.

113

Hormonal proteins

function- coordination of an organism's activities
example: insulin, a hormone secreted by the pancreas, causes other tissues to take up glucose, thus regulating blood sugar concentration

114

Receptor proteins

function- response of cell to chemical stimuli
example: receptors built into the membrane of a nerve cell detect signaling molecules released by other nerve cells

115

Contractile and Motor proteins

function- movement
examples: motor proteins are responsible for the undulations of cilia and flagella. Actin and myosin proteins are responsible for the contraction of muscles

116

Structural proteins

function- support
examples: keratin is the protein of hair, horns, feathers, and other skin appendages. Insects and spiders use silk fibers to make their cocoons and webs, respectively. Collagen and elastin proteins provide a fibrous framework in animal connective tissues.

117

Protein's monomer

amino acids

118

Protein's bond

peptide bond

119

Enzymes

are a type of protein that acts as a catalyst to speed up chemical reactions

120

Enzymes can

perform their functions repeatedly, functioning as workhorses that carry out the processes of life. (they can do the same job over and over again and never run out)

Never used up, not changed in a reaction.
Names end in --ase

121

All proteins have a

unique 3 dimensional shape

122

Polypeptides structure

Polypeptides are unbranched polymers built from the same set of 20 amino acids.

structure of an amino acid
bonds/polypeptide
primary-quaternary structure

123

A protein is a

biologically functional molecule that consists of one or more polypeptides.
it works.

124

Carbohydrate bond

glycosidic

125

lipid bond

ester linkage

126

protein bond

peptide bonds

127

Amino acids link together and form

polypeptides

128

Amino acids are a type of

monomer

129

Amino acids are

organic molecules with carboxyl and amino groups

130

Amino acids differ in their

properties due to differing side chains, called R groups

131

Cells use 20 amino acids to make

thousands of proteins.

132

they all have an amino group, carboxyl group, but the one different thing is the

R group (side chain)

133

Amino acids are linked by

peptide bonds.
between a carboxyl terminus and amino terminus

134

A polypeptide is a

polymer of amino acids

135

Polypeptides range in length from a

few to more than a thousand monomers

136

Each polypeptide has a unique linear sequence of amino acids, with

a carboxyl end (C-terminus) and an amino end (N-terminus)

137

a dehydration reaction occurs when

a new peptide bond is forming?

138

Polypeptide does NOT equal a

protein

139

A functional protein consists of

one or more polypeptides precisely twisted, folded, and coiled into a unique shape

140

Ribbon models and space filling models can

depict a protein’s conformation

141

The sequence of amino acids determines a protein’s

three-dimensional structure

142

A protein's structure determines its

function

143

Four levels of protein structure

Primary structure,
secondary structure,
tertiary structure,
quaternary structure

144

The primary structure of a protein is its

unique sequence of amino acids

145

Secondary structure, found in most proteins, consists of

coils and folds in the polypeptide chain.
a (alpha) helices and B (beta) pleated sheets

146

Tertiary structure is

determined by interactions among various side chains (R groups)

147

Quaternary structure results when a

protein consists of multiple polypeptide chains

148

Primary structure

the sequence of amino acids in a protein, is like the order of letters in a long word.

telling how to build the molecule. the names.

149

Primary structure is determined by

inherited genetic information

150

The coils and folds of secondary structure result from

from hydrogen bonds between repeating constituents of the polypeptide backbone
(why/how they form)

151

Typical secondary structures

a coil called an a (alpha) helix
a folded structure called a B (beta) pleated sheet

152

Tertiary structure is determined by

interactions between R groups, rather than interactions between backbone constituents

153

Hydrophobic R groups will orient toward

the interior

154

Hydrophilic R groups will orient toward

the exterior

155

Interactions between R groups include

hydrogen bonds
ionic bonds
hydrophobic interactions
van der Waals interactions

156

Strong covalent bonds called disulfide bridges may

reinforce the protein’s structure

157

At the point during the tertiary structure level,

many proteins are functionally complete, but not all

158

Quaternary structure results when

two or more polypeptide chains form one macromolecule

159

Collagen is a

fibrous protein consisting of three polypeptides coiled like a rope

160

Hemoglobin is a

globular protein consisting of four polypeptides: two alpha and two beta chains

161

During quaternary structure,

multiple subunits (polypeptides) have to come together

162

A slight change in primary structure can affect a protein’s

structure and ability to function
(genetic)

163

Sickle-cell disease, an inherited blood disorder, results from

a single amino acid substitution in the protein hemoglobin.
(only 1 amino acid is wrong)

164

In addition to primary structure,

physical and chemical conditions can affect structure

165

Alterations in pH, salt concentration, temperature, or other environmental factors can cause a protein to

unravel

166

This loss of a protein’s native structure is called

denaturation.
(this is really bad)

167

A denatured protein is biologically inactive

biologically inactive

168

It is hard to predict a protein’s structure from its

primary structure.
Most proteins probably go through several stages on their way to a stable structure

169

Chaperonins are

protein molecules that assist the proper folding of other proteins

170

Chaperonins help

proteins, makes sure they fold correctly.
important job!!

171

Diseases such as Alzheimer’s, Parkinson’s, and mad cow disease are associated with

misfolded proteins

172

Nucleic acids

store, transmit, and help express hereditary information

173

The amino acid sequence of a polypeptide is programmed by a unit of inheritance called a

gene

174

Genes are made of DNA, a

nucleic acid made of monomers called nucleotides

175

Genetic information flows

DNA >> RNA >> Protein

(biology's central dogma)

176

two types of nucleic acids

Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA)

177

Function of DNA

DNA provides directions for its own replication
DNA directs synthesis of messenger RNA (mRNA)

178

Function of RNA

mRNA, controls protein synthesis (helps make proteins)
Protein synthesis occurs on ribosomes

179

DNA function

-replicate
-make mRNA

180

RNA function

-protein synthesis

181

Nucleic acids are polymers called

polynucleotides

182

Nucleic acid monomers

nucleotides

183

Each polynucleotide is made of monomers called

nucleotides

184

Nucleic Acids/ Nucleotides structure

each nucleotide consists of
a nitrogenous base
a pentose sugar
and one or more phosphate group

185

The portion of a nucleotide without the phosphate group is called a

nucleoside

186

Two families of nitrogenous bases
(can change)

Pyrimidines
Purines.

187

Pyrimidines

cytosine, thymine, and uracil.
have a single six-membered ring.
one ring

188

Purines

adenine and guanine.
have a six-membered ring fused to a five-membered ring.
double/two rings

189

In DNA, the sugar is

deoxyribose

190

In RNA, the sugar is

ribose

191

Nucleotide polymers are linked together to build a

polynucleotide

192

Adjacent nucleotides are joined by covalent bonds that form between the

—OH group on the 3' carbon of one nucleotide and the phosphate on the 5' carbon on the next.

These links create a backbone of sugar-phosphate units with nitrogenous bases as appendages

193

The sequence of bases along a DNA or mRNA polymer is

unique for each gene

194

RNA molecules usually exist as

single polypeptide chains

195

DNA molecules have

two polynucleotides spiraling around an imaginary axis, forming a double helix

196

In the DNA double helix, the two backbones run in opposite 5'→ 3' directions from each other, an arrangement referred to as

antiparallel

197

One DNA molecule includes

many genes

198

The nitrogenous bases in DNA pair up and

form hydrogen bonds: adenine (A) always with thymine (T), and guanine (G) always with cytosine (C)

199

Adenine (A) always pairs up with

Thymine (T)

200

Guanine (G) always pairs up with

Cytosine (C)

201

The nitrogenous bases in DNA pairing up is called

complementary base pairing

202

Complementary pairing can also occur between

two RNA molecules or between parts of the same molecule

203

In RNA,

thymine is replaced by uracil (U) so A and U pair

204

RNA

Guanine and cytosine
Adenine and Uracil

205

DNA

Adenine and Thymine
Guanine and Cytosine

206

The linear sequences of nucleotides in DNA molecules are passed from

parents to offspring

207

Two closely related species are more similar in DNA than are

more distantly related species

208

Molecular biology can be used to assess

evolutionary kinship

209

Higher levels of organization result in the

emergence of new properties.

working way up levels of hierarchy

210

Organization is the key to the

chemistry of life