Three of the four classes of macromolecules form chainlike molecules called __________. Polymers...

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• Three of the four classes of macromolecules form chainlike molecules called __________.

• Polymers consist of many similar or identical building blocks linked by covalent bonds.

• The repeated units are small molecules called ____________.

A. Most macromolecules are _________• The four major classes of macromolecules are:

__________________________________________________________________

CHAPTER 5 THE STRUCTURE AND FUNCTION

OF MACROMOLECULES

• The chemical mechanisms that cells use to make and break polymers are similar for __________ of macromolecules.

• The __________________ connects monomers.

Fig. 5.2a

• ____________disconnects polymers

• ______________ include both sugars and polymers.

• The simplest carbohydrates are ________________

• ______________ are consist of two monosaccharides joined by a ____________ reaction.

• _________________ are polymers of monosaccharides.

B. Carbohydrates - Fuel and Building Material

• __________________:

• Molecular formulas are some multiple of CH2O.

• Usually names for sugars end in ____ ________________

• Have a carbonyl group and multiple________ groups.

• Are a major fuel for cellular work (particularly glucose)

• function as the raw material for the synthesis of other monomers, including those of _____________ and _______________

B1. Sugars, the smallest carbohydrates serve as a source of fuel and carbon sources

B.Carbohydrates

• Two monosaccharides can join with a __________ __________ to form a______________ via ________________.

• Sucrose, table sugar, is formed by joining ________and ________ and is the major transport form of sugars in plants.

B.Carbohydrates

Fig 5.5b

• Polysaccharides

• Polymers of hundreds to thousands of monosaccharides joined by _____________linkages.

• An energy storage_____________ that is hydrolyzed as needed.

• Examples of polysaccharides for fuel storage from glucose

• ___________ (animals only)

• ___________ (plants only)

• ___________- (plants only)

B2. Polysaccharides have _________ and ___________ roles

B.Carbohydrates

• One key difference among polysaccharides develops from 2 possible ______ structures of glucose.

______ - alpha glucose monomers.

Fig. 5.7b

Fig. 5.7c

_________ - (plant cell wall)- beta glucose monomers

B.Carbohydrates

Only linkage is different

Fig. 5.8

• Polysaccharide strands form ________________ with other strands.

• Groups of polymers form strong strands, ____________, that are basic building material for plants (and humans).

B.Carbohydrates

• Why can’t mammals digest __________??

• Mammalian enzymes cannot _________ the beta linkages in _________.

How can cows digest cellulose

• Cows and termites have symbiotic relationships with ____________________, allowing them access to this rich source of energy.

• _________ is _______________polysaccharide, used in the exoskeletons of ________________ (including insects, spiders, and crustaceans).

• Chitin is similar to cellulose, except that it contains a nitrogen-containing appendage on each glucose.

B.Carbohydrates

Lipids

• the exception among macromolecules because they do not form _____________.

• Little or no affinity for water.

• Why-? Mostly ______________ covalent bonds.

• Lipids are highly diverse in form and function.

C. ________ - Diverse Hydrophobic MoleculesC. Lipids

•Not strictly polymers, but assembled by ______________ reactions.

• __________ - a three carbon skeleton with a _________ group attached to each.

Fig. 5.10a

___________ – a carboxyl group attached to a long carbon skeleton, often 16 to 18 carbons long (very ______________).

C. Lipids

• A ____contains________ and _____________.C1. Fats store large amounts of energy

Fig. 5-11

In a fat, _______________ an _____________, creating a ________________.

Fig. 5.11b

The Fatty Acid chains can be the same or different

•If no carbon-carbon double bonds, then the molecule is a ___________________.

• If one or more carbon-carbon double bonds, then the molecule is an ____________________

C. Lipids

Fig. 5.12a Fig. 5.12b

• ___________fats.

• Most animal fats

• Solid at room temperature.

• Contribute to __________________ (atherosclerosis) through plaque deposits.

• _______________ fats.

• Plant and fish fats, known as oils,

• Liquid are room temperature.

• The _______ provided by the ____________ prevent the molecules from packing tightly together.

C. Lipids

• The major function of fats is ________________.

• A gram of fat stores more than ______ as much energy as a gram of a polysaccharide.

• Plants use ________ for energy storage when mobility is not a concern but use _______when dispersal and packing is important, as in seeds.

• Mammals store fats as long-term energy reserves in ____________ cells.

• Other functions- ___________ vital organs and ________________.

C. Lipids

• ____________ = a fat with _____ fatty acids attached to _________ plus a ____________ group at the third position.

• Additional smaller groups may be attached to the __________ group.

C2. Phospholipids are major components of cell membranes

Hydrophobic tail

Hydrophilic head

C. Lipids

Fig. 5-13

• A cell surface contains ________________ arranged as a _______

• hydrophilic heads on the outside

• hydrophobic tails form the core

C. Lipids

Fig. 5.14

• Steroids are_______ with a carbon skeleton consisting of four fused carbon _____.

• Different steroids are created by varying __________ groups attached to the rings.

C3. Steroids include cholesterol and certain hormones

Fig. 5.15

• ____________ • component in animal cell

membranes.

• precursor of all other _______ (including hormones)

• high levels in the blood may contribute to ___________ disease.

C. Lipids

D. Proteins• Functions include structural support, storage, transport of

other substances, intercellular signaling, movement, and defense against foreign substances.

Humans have ________________ of different proteins, each with their own _______ and ____________.

• All protein polymers are constructed from the same set of __ monomers, called _______________.

• Polymers of proteins are called _____________.

• A protein = one or more polypeptides folded and coiled into a specific _____________.

D. Proteins

• _____________ consist of four components attached to a central carbon, the ______________.

1. ______________

2. _______________

3. _______________ (or side chain).

D1. A polypeptide is a polymer of amino acids connected in a specific sequence

R

4. __________________

Differences in _________ produce the ___ different amino acids.

D. Proteins

• One group of amino acids has ________, ________ R groups.

• Another group of amino acids has ______R groups, making them ____________.

D. Proteins

Rule of thumb- If R= only

CH3 groups,

then _________

Rule of thumb- If R has -OH

or =O groups,

then _____

Fig. 5.17a

• The last group of amino acids includes those with functional groups that are__________ (ionized) at cellular pH.

• Some R groups are bases, others are acids.

Fig. 5.17c

D. Proteins

If R has _____. then _____ If R has ___ then ______

• Amino acids are joined in a __________________

• The resulting _________ bond is called a ___________.

Fig. 5.18

D. Proteins

• The order of amino acids determines the three-dimensional conformation, hence the _________.

D2. A protein’s function depends on its specific conformation

Fig. 5.19

• The function of a protein is an ______________________ resulting from its specific molecular order.

• Three levels of structure: _______________________________and ___________________

D. Proteins

• The_________ structure of a protein is its unique _________ of amino acids.

• Sickle cell disease, abnormal hemoglobins, is due to a single __________ substitution.

Normal Sickle cell

D. Proteins

• The ____________ structure -hydrogen bonds at regular intervals along the polypeptide backbone.

• Typical shapes

-_____ (an alpha helix)

-_____ (beta pleated sheets).

D. Proteins

Not in text

• ________ structure - determined by interactions among between ________ and the___________backbone.

4. _____________- strong covalent bonds that form between the sulfhydryl groups (SH) of cysteine monomers, stabilize the structure.

D. Proteins

1. _________ bonds 2. ___________interactions

3. _______ bonds

Page 83

• ______________ structure results from the aggregation of ____________ polypeptide subunits.

• ___________- fibrous protein of three polypeptides that are supercoiled like a rope.

• _____________- a globular protein with ____ copies of _____kinds of polypeptides.

D. Proteins

HemaglobinCollagen

Page 83

Review of protein structureD. Proteins

• Alterations in ______________________________, or other factors can unravel or __________ a protein.

Disrupt the hydrogen bonds, ionic bonds, and disulfide bridges that maintain the protein’s shape.

• Some proteins can return to their functional shape after ___________________, but others cannot.

D. Proteins

Fig. 5-22

Fig. 5.23

• The folding of many proteins is protected by _________________ proteins.

D. Proteins

E. Nucleic acids store and transmit hereditary information

• A gene consists of regions of DNA, a polymer of ______ ____________

• Two types of nucleic acids: _________________ (RNA) and _________________ (DNA).

• DNA provides direction for its own replication.

• DNA makes____ makes _____.

• DNA is the basis of inheritance

• One gene synthesizes one RNA

E. Nucleic Acids

Fig. 5-25

E. Nucleic Acids

______components in nucleic acids-

2. _____________

1.____

3. ____

DNA –__ at the “2” carbonRNA –___ at the “2” carbon

Fig. 5.26c Fig. 5.26 a and b

E. Nucleic AcidsThree components in nucleic acids-

1. Base

Two classes of bases

Polynucleotides are connected by _________________________________.

Fig. 5.26c

• An RNA molecule is single _____________ chain.

• DNA molecules have _____ polynucleotide strands that spiral around an imaginary axis to form a __________________.

• The ______________ was first proposed as the structure of DNA in 1953 by James Watson and Francis Crick.

E21. Inheritance is based on replication of the DNA double helix

E. Nucleic Acids

• The _______________ backbones of the two polynucleotides are on the outside of the helix.

• Pairs of___________________, one from each strand, connect the polynucleotide chains with hydrogen bonds.

• Most DNA molecules have thousands to millions of base pairs.

Fig. 5.27

E. Nucleic Acids

• Because of their shapes, only some bases are compatible with each other.

• Adenine (A) always pairs with ______________ and guanine (G) with _____________

• if we know the sequence of bases on one strand, we know the sequence on the opposite strand.

• The two strands are _________________.

E. Nucleic Acids

• Each strand is copied into to make two identical __________ of the original double-stranded DNA molecule.

• The copies are then distributed to the _________________ cells.

• Genes (___) and their products (_________) document the hereditary background of an organism.

• Because DNA molecules are passed from parents to offspring, __________ have greater similarity than do ____________ individuals of the same species.

• This argument can be extended to develop a molecular ________________ between species.

4. We can use DNA and proteins as tape measures of_____________

E. Nucleic Acids

• In theory, two species that ________ to be closely-related based on fossil and molecular evidence should also be more similar in DNA and protein sequences than are _____________ related species.

• In fact, the sequence of amino acids in hemoglobin molecules differ by only _______________ between humans and gorilla.

• More distantly related species have more differences.

E. Nucleic Acids

E. Nucleic Acids