AP BioII Chap.5/8 Test

List the four major classes of macromolecules

Carbohydrates, Lipids, Proteins, Nucleic Acids

Distinguish between monomers and polymers

Monomers are the small molecules that make up a Polymer. A Polymer is a long chain consisting of monomers that are connected by covalent bonds.

Condensation and Hydrolysis reactions


Distinguish among monosaccharides, disaccharides, and polysaccharides.

monosaccharides: simplest carb and is the monomer for disaccharides and polysaccharides
disaccarides: a double sugar, two monosaccharides bonded together using glycosidic linkage
polysaccharides: a polymer of many monosaccharides

Describe the formation of glycosidic linkage

A covalent bond formed between two sugars

Distinguish between glycosidic linkages found in starch and cellulose. Explain why the difference is biologically important.

Starch has alpha glycosidic linkages and cellulose has beta glycosidic linkage. Is important because we have an enzyme that breaks down the alpha but not the beta.

Describe the role of symbiosis in cellulose digestion.

Symbiosis: ecological relationship between different organisms (cow, bacteria), stuff living inside of other things, beneficial and not so beneficial.
The role in cellulose digestion is bacteria breaks down cellulose for the host cow/bull.

Describe the building-block molecules, structure, and biological importance of fats, phospholipids, and steroids.

Fats: are constructed of a glycerol + 3 fatty acids. (saturated fats = bad)
Phospholipids: make up cell membranes; glycerol + 2 fatty acids
Steroid: hormones/cholesterol; four fused rings

Identify an ester linkage and describe how it is formed.

Found in fats and connect a glycerol and three fatty acids.

Distinguish between saturated and unsaturated fats.

Saturated: no double bonds, straight chains of hydrogen and carbon, solid at room temp
Unsaturated: one or more double bonds formed by removal of hydrogen atoms, liquid at room temperature, bent chains of carbon and hydrogen

Name the principle energy storage molecules of plants and animals

Plants: starch stores the energy
Animales: glycogen(made in your liver) store the energy

Distinguish between a protein and a polypeptide

Protein: many structures, wide variety of functions, made up of polypeptides
Polypeptide: amino acid sequence (chain), part of the protein

Explain how a peptide bond forms between two amino acids.

A dehydration reaction covalently bonds amino group of one amino acid with carboxyl group of another amino acid

List and describe the four major components of an amino acid. Explain how amino acids may be grouped according to the physical and chemical properties of the R group.

Amino group
Carboxyl Group
Hydrogen Atom
R Group: determines qulaity (polar, nonpolar, etc.)

Explain what determines protein conformation and why it is important.

Polypeptide has to have best environment(temp,pH). Important because if not in good conditions it unravels and can not do the right job. (denaturation)

*Explain how the primary structure of a protein is determined.

primary structure: DNA tells the amino acid order. bonded with peptide bonds.

*Name two types of secondary protein structures. Explain the role of hydrogen bonds in maintaining secondary structure.

Secondary: Alpha Helix and Beta Pleated Sheet
They are made by hydrogen bonds.

*Explain how weak interactions and disulfide bridges contribute to tertiary protein structure.

tertiary structure has disulfide bridges. covalent bond. ionic bonding. hydrogen bonds. vanderwalls. needs all of these bonds to keep the right shape.

List four conditions under which proteins may be denatured.

heat, acid, salt

List the major components of a nucleotide and describe how these monomers are linked to form a nucleic acid.

nitrogen base, pentose sugar, phosphate group
sugars and phosphates: ladder upright; covalent bonds
bases: rungs of the ladder (purine bonds with a pyrimidine); hydrogen bonds (weakest)

pyrimidine and purine
nucleotide and nucleoside
ribose and deoxyribose
5' end and 3' end

pyrimidine: C.T.U. (think structure of DNA)
purine: A.G.
nucleotide: base+sugar+phosphate
nucleoside: base+sugar
ribose: RNA
deoxyribose: DNA
5': front
3': back
example: 5' ATTCGA 3' > 3' TAAGCT 5' : complimentary DNA strands

Briefly describe the three-dimensional structure of DNA

A double-helix consisting of two anti-parrallel nucleotide strands. There is a spiral around an imaginary axis.

Explain the role of catabolic and anabolic pathways in cellular metabolism.

Catabolic: degradative process such as cellular respiration; release of energy
Anabolic: building process such as protein synthesis; consumes energy

Distinguish between kinetic and potential energy.

Kinetic: energy of motion
Potential: stored energy

Explain the first and second laws of thermodynamics.

First: conservation of energy. energy transferred or transformed. cannot be created or destroyed.
Second: Transformations increase entropy (disorder or randomness)
COMBO: quantity is constant not quality

List the three main kinds of cellular work. Explain in general terms cells obtain the energy to do cellular work.

Chemical Work, Mechanical Work, and Transport Work.
plant gets energy from photosynthesis process
and animals depend on plants for the energy.

Describe the structure of ATP and identify the major class of macromolecules to which ATP belongs.

Adenosine Triphosphate
ATP tail: high negative charge
ATP hydrolysis: release of free energy

Explain how ATP performs cellular work.

It either heats up the cell but usually it creates energy to be used by proteins to do other work

Describe the functions of enzymes in biological systems.

they act as catalysts to reactions, thus lowering the energy required for a reaction to proceed to formation of product.

Explain how enzyme structure determined enzyme specificity.

Because of this specific shape, and due to the different interactions between the amino acids, the shape of the enzyme is rigid enough to only allow certain molecules into the active site, but repelling others because they don't fit. Because this is in 3D

Explain the induced fit model of enzyme function.


Explain how temperature, pH, cofactors, and enzyme inhibitors can affect enzyme activity.

Temperature affects enzyme activity because enzymes are made of proteins and as the temperature raises, the protein's molecular structure will be more and more unstable until it denatures and breaks apart. The pH works essentially the same where the enzym

alpha helix

A spiral shape constituting one form of the secondary structure of proteins, arising from a specific patter of hydrogen bonding.


The opposite arrangement of the sugar-phosphate backbones in a DNA double helix.

beta pleated sheet

One form of the secondary structure of proteins in which the polypeptide chain folds back and forth. Two regions of the chain lie parallel to each other and are held together by hydrogen bonds.


A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides).


A protein molecule that assists in the proper folding of other proteins.


a structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.


A steroid that forms an essential component of animal cell membranes and acts as another molecule for the synthesis of other biologically important steroids, such as hormones.

double helix

The form of native DNA, referring to its two adjacent antiparallel polynucleotide strands wound around an imaginary axis into a spiral shape.

fatty acid

A long carbon chain of carboxylic acid. Fatty acids vary in length and in the number and location of double bonds; three fatty acids linked to a glycerol molecule form a fat molecule, also known as a triacylglycerol or triglyceride.


A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).


An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.

hydrophobic interaction

A type of weak chemical bond formed when molecules that do not mix with water coalesce to exclude water.


One of a group of compounds, including fats, phospholipids, and steroids, that mix poorly, if at all, with water.


A polymer consisting of may nucleotide monomers in a chain; nucleotides can be those of DNA or RNA.

quaternary structure

The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide.

X-ray crystallography

A technique that depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule to study the three-dimensional structure of the molecule.

activation energy

The amount of energy that reactants must absorb before a chemical reaction will start; also called free energy of activation.

active site

The specific portion of an enzyme that binds the substrate by means of multiple weak interactions and that forms the pocket in which catalysis occurs.

allosteric regulation

The binding of a regulatory molecule to a protein at one site that affects the functions of the protein at a different site.


(1) The overall flow and transformation of energy in an organism. (2) The study of how energy flows through organisms.


A chemical agent that increases the rate of a reaction without being consumed by the reaction

chemical energy

Energy available in molecule's for release in a chemical reaction; a form of potential energy.


An organic molecule serving as a cofactor. Most vitamins function as coenzymes in metabolic reactions.

competitive inhibitor

A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics


A kind of allosteric regulation whereby a shape change in one subunit of a protein caused by substrate binding is transmitted to all the others, facilitation binding of subsequent substrate molecules.

endergonic reaction

A non-spontaneous chemical reaction, in which free energy is absorbed from the surroundings.


The capacity to cause change, especially to do work (to move matter against an opposing force).

energy coupling

In cellular metabolism, the use of energy released from an exergonic reaction to drive an endergonic reaction.


A measure of randomness or disorder.

enzyme-substrate complex

A temporary complex formed when an enzyme binds to its substrate molecule.

exergonic reaction

A spontaneous chemical reaction, in which there is a net realise of free energy.

feedback inhibition

A method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway.

free energy

The portion of a biological system's energy that can perform work when temperature and pressure are uniform throughout the system. *the change in free energy of a system is calculated by the equation G=H-TS, where H is enthalpy [in biological systems, equ

free energy of activation

the energy required to break bonds

metabolic pathway

A series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule into simpler compounds (catabolic pathway)


The totality of an organism's chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of the organism

noncompetitive inhibitor

A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing the enzyme's shape so that the active site no longer functions effectively.


Refering to a molecule that is covalently bonded to a phosphate group.


The reactant on which an enzyme works.

thermal energy

The total amount of kinetic energy due to the random motion of atoms or molecules in a bond of matter; also called thermal energy. Heat is energy in its most random form.