Modern Biology Chapter 3

Distinguish between organic and inorganic compound.

Inorganic compounds have no carbon except for a few exceptions. Organic compounds are made primarily from carbon.

Explain the importance of carbon bonding in biological molecules.

The tendency that carbon has to bond with itself results in a large variety of organic compounds.

Identify the four functional groups of biological molecules.

Functional groups are hydroxyl, carboxyl, amino and phosphate.

What do the functional groups do?

The functional groups modify the molecule that they are attached to. The hydroxyl group makes the molecule its attached to hydrophilic or polar.

Summarize how large molecules are synthesized and broken down.

Molecules are synthesized through a condensation reaction that involves the removal of water. They are broken down by a hydrolysis reaction which entails the addition of water into a compound, thus breaking down the bonds between the molecules.

Describe how the breaking down of ATP supplies energy to drive chemical reaction.

The hydrolysis of ATP (to the phosphate group) is used by the cell to provide the energy needed to drive the chemical reactions that enable the organism to function. This is easy because the phosphate groups are more unstable that then other bonds in the

How many valence electrons does carbon have?


What are three shapes that carbon bonds can form?

straight carbon chain, branched carbon chain, carbon ring

What is the maximum number of bonds that any carbon atom can form?

four, a quadruple bond.

Name the types of carbon bonds.

single, double, triple, quadruple

What are many carbon bonds built up from?

smaller simpler molecules known as monomers.

What can monomers form by bonding to one another?


What are large polymers known as?


Name four types of macromolecules.

nucleic acids, lipids, proteins, carbohydrates

What is the process through which monomers bond to form polymers?

condensation reactions

Complex molecules are broken down in a process known as ____________?


What does ATP stand for?


What does the hydrolysis of ATP yield?

ADP (adenosinediphosphate) and inorganic phosphate

Name the groups that compose ATP.

five carbon sugar (ribose), nitrogen containing compound (adenine), and the three linked phosphate groups

Name the groups that compose ADP.

Same as ATP, but only two linked phosphate groups

Condensation reactions are also referred to as dehydration synthesis. Describe how dehydration synthesis is descriptive of the process.

The process dehydrates the compound by removing the water and synthesizes a new compound.

Distinguish between monosaccharides, polysaccharides, and disaccharides.

Mono sac is a simple sugar, such as fructose. A di sac results when two monomers react to one another in a condensation reaction. A poly sac is a long complex chain of sugars, such as galactose and starch.

Explain the relationship between amino acids and protein structure.

Proteins are organic compounds made mainly of carbon, hydrogen, oxygen and nitrogen. Like most of the other biological macromolecules, proteins are formed from the linkage of monomers known as amino acids. Proteins have many functions such as structural,

Describe the induced fit model of enzyme action.

1. A certain enzyme attaches to a specific substrate/
2. The enzyme then changes and reduces the activation energy of the reaction so that reactants can become products.
3. The enzyme is unchanged and is ready to be used again.

Compare the structure and function of each of the types of lipids.

Triglycerides are composed of three molecules of fatty acid joined to one molecule of the alcohol glycerol. Phospholipids have two rather than three molecules of fatty acids joined to one molecule of glycerol. A wax is a type of structural lipid consistin

Name the four types of lipids.

triglycerides, phosholipids, steroids, waxes

Describe a fatty acid.

Fatty acids are unbranched carbon chains that make up most lipids. They are composed of 12-28 carbons with a carboxyl group, COOH, attached at one end. The carboxyl end is polar and is attracted to water. In contrast the hyrdocarbon end of the fatty acid

What is the ratio of carbon, hydrogen, and oxygen in monosaccharide?

1:2:1, respectively

What are isomers?

Compounds with a single chemical formula, but different structural forms.

What is a peptide bond?

Peptide bond is a covalent bond between two amino acids.

What is a polypeptide?

A very long chain of amino acids. Proteins are composed of one or more amino acids.

What are the two functions of nucleic acid?

To store and transfer important information in the cell.

What are the two major types of nucleic acid?


What is the function of DNA?

DNA contains information that determines the characteristics of an organism and directs its cell activities.

What is the function of RNA?

RNA stores and transfers information from DNA that is essential for the manufacturing of proteins; they can act as enzymes.

DNA and RNA are what?

Polymers composed of thousands of linked monomers.

What are the monomers of nucleic acid?


What are the three components of a nucleotide?

phosphate group, 5 carbon sugar, ring shaped nitrogenous base

Carbohydrates such as glucose are what?

A source of energy and used as structural material in organisms.

What are enzymes?

RNA or protein molecules that act as biological catalysts that bind to specific substrates and reduce the activation energy of a reaction.

What is a single bond?

a bond formed when two atoms share one pair of electrons

What symbol represents a single bond? double bond? triple bond?

one parallel line, two parallel lines, three parallel lines, respectively

What is a functional group?

Clusters of atoms, found in most organic compounds, that influence the molecules they compose and the chemical reactions the molecules undergo.

Define hydrophilic. Give an example of a hydrophilic molecule.

Soluble in water. Polar molecules.

What is an alcohol?

Organic compound with a hydroxyl group attached to one of its carbon atoms.

The hyrdoxyl group makes an alchohol a ___________.

polar molecule

What is the reverse of a condensation reaction?


What is a carbohydrate?

organic compounds composed of carbon, hydrogen, and oxygen in a ration of 1:2:1 respectively

What is another term for monosaccharide?

simple sugar

What is the main source of energy for cells?


What is the sweetest of the monosaccharides?

fructose, found in plants

Galactose is found in what?


What has the same chemical formula but different structures?

glucose, fructose, and galactose

Define glycogen.

a polysaccharide, glucose, stored in animals

Plants store glucose in the form of ________.


Name the two forms of starch molecule.

highly branched chains similar to glycogen and long, coiled unbranched chains

Plants make a large polysaccharide known as :


What is the purpose of cellulose?

gives strength and rigidity to plant cells, makes up 50% of wood

How many different amino acids are there? And, do they share a basic structure?

20; yes

What is a substrate?

the reactant being catalyzed.

What is an active site?

folds with the shape that allows the substrate to fit

An enzyme may not work if what is changed?

Its environment

What is a lipid?

large, nonpolar organic molecules that do not dissolve in water and have a higher ratio of carbon and hydrogen atoms to oxygen atoms than carbohydrates have.

Lipids store more energy than carbohydrates.


What is a saturated fatty acid?

each carbon atom is covalently bonded to four atoms and the atoms are "Full" or saturated.

What is an unsaturated fatty acid?

double bonds within the carbon chain,

Define lipid bilayer.

cell membrane made of two layers of phospholipids which forms a barrier to water

What does an enzyme do?

Speeds up chemical reactions and bind to specific substrates. The binding of a substrate with the enzyme causes a change in the enzyme's shape and reduces the activation energy of the reaction.

Discuss lipids.

Lipids are nonpolar molecules that store energy and are an important part of cell membranes. Most lipids contain fatty acids, molecules that have a hydrophilic end and an hydrophobic end.

Go to page 62 and know all the key concepts and review critical thinking.

Finito!! Good work!!