AP Biology

ANNOUNCEMENTS UNIT 3 Ecology Exam Average:

Summa Cum Laude:

Magna Cum Laude:

Mastered with a 80% or above:

70%

Raymond

Tevin

Jonathon, Markell, Justin, Roslynn, Lavel, Matthew`

AP Biology

Carbohydrates Structure / monomer

monosaccharide

Function energy raw materials energy storage structural compounds

Examples glucose, starch, cellulose, glycogen

glycosidic bond

AP Biology 2006-2007

Lipidslong term energy storage

concentrated energy

AP Biology

Lipids Lipids are composed of C, H, O

long hydrocarbon chains (H-C)

“Family groups” fats phospholipids steroids

Do not form polymers big molecules made of smaller subunits not a continuing chain

AP Biology

Fats Structure:

glycerol (3C alcohol) + fatty acid fatty acid =

long HC “tail” with carboxyl (COOH) group “head”

dehydration synthesis

H2O

enzyme

AP Biology

Building Fats Triglyceride

3 fatty acids linked to glycerol ester linkage = between OH & COOH

hydroxyl carboxyl

AP Biology

Dehydration synthesis

dehydration synthesis

H2O

H2O

H2O

H2O

enzyme

enzyme

enzyme

AP Biology

Fats store energy Long HC chain

polar or non-polar? hydrophilic or hydrophobic?

Function: energy storage

concentrated all H-C!

2x carbohydrates cushion organs insulates body

think whale blubber!

Why do humanslike fatty foods?

AP Biology

Saturated fats All C bonded to H MORE HYDROGENS!

long, straight chain most animal fats solid at room temp.

contributes to cardiovascular disease (atherosclerosis) = plaque deposits

AP Biology

Unsaturated fats C=C double bonds in

the fatty acids plant & fish fats vegetable oils liquid at room temperature

the kinks made by doublebonded C prevent the molecules from packing tightly together

mono-unsaturated?poly-unsaturated?

AP Biology

Saturated vs. unsaturatedsaturated unsaturated

AP Biology

Phospholipids Structure:

glycerol + 2 fatty acids + PO4

PO4 = negatively charged

It’s just like apenguin…

A head at one end& a tail

at the other!

AP Biology

Phospholipids Hydrophobic or hydrophilic?

fatty acid tails = PO4 head = split “personality”

interaction with H2O is complex & very important!

“repelled by water”

“attracted to water”

Come here,No, go away!Come here,

No, go away!

hydrophobic

hydrophillic

AP Biology

Phospholipids in water Hydrophilic heads “attracted” to H2O

Hydrophobic tails “hide” from H2O

bilayer

water

water

AP Biology

Why is this important? Phospholipids create a barrier in water

define outside vs. inside they make cell membranes!

Tell themabout soap!

AP Biology

Steroids Structure:

4 fused C rings + ?? different steroids created by attaching different

functional groups to rings different structure creates different function

examples: cholesterol, sex hormones

cholesterol

AP Biology

Cholesterol Important cell component

animal cell membranes precursor of all other steroids

including vertebrate sex hormones high levels in blood may contribute to

cardiovascular disease

AP Biology

D.N.AObjective: Describe the four levels of protein conformation and relate them to reversable and nonreversable denaturation

Label the definition with the correct macromolecule

A. Proteins

B. Carbohydrates

C. Nucleic acids

D. Lipids

E. Steroids

1. Synthesized at the ribosome

2. Includes glycogen, chitin, cellulose, and glucose

3. Used for insulation and buoyancy in marine Arctic animals

4. Used to carry the genetic code

AP Biology 2008-2009

ProteinsMultipurpose

molecules

AP Biology

Proteins Most structurally & functionally diverse group Function: involved in almost everything

enzymes structure (keratin, collagen) carriers & transport (hemoglobin, aquaporin) cell communication

signals (insulin & other hormones) receptors

defense (antibodies)

AP Biology

Proteins Structure

monomer = amino acids 20 different amino acids

growthhormones

H2O

AP Biology

Amino acids Structure

central carbon amino group carboxyl group (acid) R group (side chain)

variable group different for each amino acid confers unique chemical

properties to each amino acid like 20 different letters of an

alphabet can make many words (proteins)

—N—H

HC—OH

||O

R

|—C—

|

H

Oh, I get it!amino = NH2 acid = COOH

AP Biology

Building proteins Peptide bonds

covalent bond between NH2 (amine) of one amino acid & COOH (carboxyl) of another

C–N bond

peptidebond

dehydration synthesisH2O

AP Biology

Protein structure & function

hemoglobin

Function depends on structure 3-D structure

twisted, folded, coiled into unique shape

collagen

pepsin

AP Biology

Primary (1°) structure Order of amino acids in chain

amino acid sequence determined by gene (DNA)

slight change in amino acid sequence can affect protein’s structure & its function even just one amino acid change

can make all the difference!

lysozyme: enzyme in tears & mucus that kills bacteria

AP Biology

Sickle cell anemia

I’mhydrophilic!

But I’mhydrophobic!

Just 1out of 146

amino acids!

AP Biology

Secondary (2°) structure “Local folding”

folding along short sections of polypeptide interactions between

adjacent amino acids H bonds

weak bonds between R groups

forms sections of 3-D structure -helix -pleated sheet

AP Biology

Tertiary (3°) structure “Whole molecule folding”

interactions between distant amino acids hydrophobic interactions

cytoplasm is water-based

nonpolar amino acids cluster away from water

H bonds & ionic bonds disulfide bridges

AP Biology

Quaternary (4°) structure More than one polypeptide chain bonded

together only then does polypeptide become

functional protein hydrophobic interactions

collagen = skin & tendons hemoglobin

AP Biology

Protein structure (review)

amino acid sequence

peptide bonds

1°

determinedby DNA R groups

H bonds

R groupshydrophobic interactions

(H & ionic bonds)

3°multiple

polypeptideshydrophobic interactions

4°

2°

AP Biology

Protein denaturation Unfolding a protein

temperature pH salinity

alter 2° & 3° structure alter 3-D shape

destroys functionality some proteins can return to their functional shape

after denaturation, many cannot

In Biology,size doesn’t matter,

SHAPE matters!

AP Biology

CREATE A CONCEPT MAP

In a group of 4, each person is responsible for creating a concept map for one of the macromolecules

Carbohydrates Lipids Proteins Nucleic Acids

AP Biology

AP Biology

Nucleic AcidsInformation

storage

AP Biologyproteinsproteins

DNADNA

Nucleic Acids Function:

genetic material stores information

genesblueprint for building proteins

DNA RNA proteins

transfers informationblueprint for new cellsblueprint for next generation

AP Biology

AA

A

A

TC

G

CG

TG

C

T

AP Biology

Nucleic Acids Examples:

RNA (ribonucleic acid) single helix

DNA (deoxyribonucleic acid) double helix

Structure: monomers = nucleotides

RNADNA

AP Biology

Nucleotides 3 parts

nitrogen base (C-N ring) pentose sugar (5C)

ribose in RNA deoxyribose in DNA

phosphate (PO4) group

Nitrogen baseI’m the

A,T,C,G or Upart!

AP Biology

Types of nucleotides 2 types of nucleotides

different nitrogen bases purines

double ring N base adenine (A) guanine (G)

pyrimidines single ring N base cytosine (C) thymine (T) uracil (U)

Purine = AGPure silver!

AP Biology

Nucleic polymer Backbone

sugar to PO4 bond

N bases hang off the sugar-phosphate backbone

AP Biology

Pairing of nucleotides Nucleotides bond between

DNA strands H bonds purine :: pyrimidine A :: T

2 H bonds G :: C

3 H bonds

Matching bases?Why is this important?

AP Biology

DNA molecule Double helix

H bonds between bases join the 2 strands A :: T C :: G

H bonds?Why is this important?

AP Biology

Copying DNA Replication

2 strands of DNA helix are complementary have one, can build other have one, can rebuild the

whole

Matching halves?Why is this

a good system?

AP Biology

When does a cell copy DNA? When in the life of a cell does DNA have

to be copied? cell reproduction

mitosis gamete production

meiosis

AP Biology

DNA replication“It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.”

James WatsonFrancis Crick

1953

AP Biology

Watson and Crick … and others…1953 | 1962

AP Biology

Maurice Wilkins… and…1953 | 1962

AP Biology

Rosalind Franklin (1920-1958)

AP Biology

Interesting note… Ratio of A-T::G-C

affects stability of DNA molecule 2 H bonds vs. 3 H bonds biotech procedures

more G-C = need higher T° to separate strands

high T° organisms many G-C

parasites many A-T (don’t know why)

AP Biology

Another interesting note… ATP

Adenosine triphosphate

++

modified nucleotide adenine (AMP) + Pi + Pi