BENCHMARK SC.912.L.18.1Describe the basic molecular structures and primary functions of the four major categories of biological macromolecules.

Explain the role of enzymes as catalysts that lowerthe activation energy of biochemical reactions.

Identify factors, such as pH and temperature, and their effect on enzyme activity.

Activation energy is like a wall that is needed to be climbed!!!!So the enzyme simply lower the wall.The factors that affect enzyme activity are limitedto concentration, pH, and temperature. All Enzymes have an ideal concentration, pH, and temperature which they work best at. They become denatured when those factors are increased or decreased. Within the range of those 3 factors enzymes work better when the concentration, pH, and temperature are adjusted for optimal performance. These factors are a way your body turns off enzymes.

Students will identify and/or describe the basic molecular structureof carbohydrates, lipids, proteins, and/or nucleic acids.

Students will describe the primary functions of carbohydrates, lipids,proteins, and/or nucleic acids in organisms.

Students will explain how enzymes speed up the rate of a

biochemical reaction by lowering the reaction’s activation energy. Students will identify and/or describe the effect of environmental

factors on enzyme activity.

Know the structure and function of all 4 macromolecules • Within cells, small organic molecules called monomers are joined together to form

larger molecules, known as Macromolecules. Monomers============ MacromoleculesGlucose(monosaccharide)===============Sugar(carbohydrate)Amino acid=============ProteinFatty acids==============Lipid

• Each cell has thousands of different kinds of macromolecules. • Macromolecules vary among cells of an organism, vary more within a species, and vary

even more between species.

• Carbohydrates - short term energy storage; structure of some organisms• Lipids - (also known as fats) - long term energy storage• Nucleic Acids (DNA and RNA) - the instructions the cell uses to build proteins• Proteins (Polypeptides): The highly variable macromolecules that make each organism

unique

Used for energy in all organisms and for structure in plants.

Carbohydrates

Sugars & Starches

Sugar• Function: Monosaccharides serve as a major fuel for cells and as raw material for

building molecules • Monosaccharides have molecular formulas that are usually multiples of CH2O – 1:2:1

ratio• Glucose, fructose, and galactose is the most common monosaccharide• Structure: though often drawn as a linear skeleton, in aqueous solutions they form rings

• Di- = two

• Examples: Lactose (milk sugar) & Sucrose

Disaccharides (sugars) =2 monosaccharides linked

together.

• Poly- = Many • Glycogen = Used as energy

storage in animals.

• Cellulose = Used to form the cell wall of plants.

• Chitin- is found in the exoskeleton of arthropods and the cell walls of many fungi

Storage and Structure Polysaccharides

3 or more monosaccharides linked.

Storage of Polysaccharides• Starch, a storage polysaccharide of plants, consists entirely of glucose monomers• Plants store surplus starch as granules within chloroplasts and other plastids •

The white thingy is polysaccharide !!!

Glucosemonomer

0.5 µm

Plant cells

MicrofibrilCell walls

Cellulose microfibrilsin a plant cell wall

Cellulosemolecules

LE 5-8

• Enzymes that digest starch by hydrolyzing alpha linkages can’t hydrolyze beta linkages in cellulose

• Cellulose in human food passes through the digestive tract as insoluble fiber• Some microbes use enzymes to digest cellulose• Many herbivores, from cows to termites, have symbiotic relationships with these

microbes

And from???????? X believe it or not!!!!!! Lobster carapace with portabella ,yummy!

Lipids are a diverse group of hydrophobic(water hating) molecules

• Lipids are the one class of large biological molecules that do not form polymers

• The unifying feature of lipids is having little or no affinity for water

• Lipids are hydrophobic because they consist mostly of hydrocarbons, which form nonpolar covalent bonds

• The most biologically important lipids are fats, sterols and phospholipids.

Lipids Used for long-term energy

storage.

The first group is Fats

Saturated FatNo Double Bonds only single bonds between Carbons (C-C)

Unsaturated FatDouble Bonds between the Carbons (C=C)

Saturated fats are solids at room temperature. (fat and butter)

Unsaturated fats are liquids at room temperature. (Oils)

Second group Phospholipids

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

• The structure of phospholipids results in a bilayer arrangement found in cell membranes• Phospholipids are the major component of all cell membranes

You must be able to recognize the structure for EOC

Steroids

1. Considered lipids because they are hydrophobic!!2. Consist of 4 fused rings3. Cholesterol is a steroid

Nucleic Acids

DNA – your genetic code sugar is deoxyribose missing Oxygen

RNA – used to make proteins

DNA & RNA = Polymers of nucleic acids

Nucleotide = monomer of nucleic acids.

• DNA – di=2 (α-helix) carries the information on how to make proteins. Mostly 2 strands. (1-strand DNA (ssDNA) found in viruses) • RNA is directly involved in making proteins. Mostly 1 strand. (2-strand RNA (dsRNA) found in viruses )

Nucleotide has 3 parts:

- phosphate

- 5-carbon sugar

- nitrogen base.

Base Pairing Rule

At Coral Gables A=T C=G

Protein

Proteins have many structures, resulting in a wide range of functions

• Proteins account for more than 50% of the dry mass of most cells• Protein functions include enzymes*,structural support, storage, transport, cellular communications, movement, and

defense against foreign substances• Different functions=different shapes

Structure of Amino Acids

Four Levels of Protein Structure

Primary structure of a protein is its unique sequence of amino acids.

The major building block in living things. Muscles, enzymes, antibodies, cell structure

• Protein = Polypeptide (polymer) comprised of monomers (amino acids). There are 20 different amino acids.

• Amine Group (NH2)-Basic• Carboxylic Acid Group (COOH) –

Acidic• The center asymmetrical carbon is

called the alpha carbon. • The R group (think random) is

variable for each amino acid! Also called the side chain.

Secondary structure, found in most proteins, consists of coils and folds in the polypeptide chain. The sequence of amino acids converts into 1 of 2 forms

» α-helix

» β-pleated sheets

Tertiary structure is determined by interactions among various side chains (R groups)

Quaternary structure results when a protein consists of multiple polypeptide chains

Not found in all proteins

Same bonds/interactions as tertiary level

Identify the Amino acid structures below.

Protein Denature

• Denaturation• Protein unravels and loses its native conformation

• Structure & Function• Change in the protein’s structure = loss of function

• Denaturation occurs:1. Organic solvent2. Any chemical that disrupts the tertiary structure3. Heat (excessive)

As food travels through the digestive system, it is exposed to a variety of pH levels. Thestomach has a pH of 2 due to the presence of hydrochloric acid (HCl), and the small intestinehas a pH ranging from 7 to 9. HCl converts pepsinogen into pepsin, an enzyme that digestsproteins in the stomach. Which of the following most likely happens to pepsin as it enters thesmall intestine?

A. It becomes inactive.B. It begins to replicate.C. Its shape changes to engulf large proteins.

D. Its activity increases to digest more proteins.