Chapter 4

What is a hydroxyl group?

-OH; Oxygen and hydrogen bonded to a carbon.

Carbon's atomic number is 6. This means that it has __________ electrons. After completing the first energy level, carbon has __________ valence electrons and can form __________ bonds.

6; 4; 4

How many biologically important functional groups are there?

7

Which statement about a methyl functional group is correct? - A methyl group is polar. - A methyl group may be negatively charged. - A methyl group consists of a carbon bonded to three hydrogen atoms.

A methyl group consists of a carbon bonded to three hydrogen atoms.

Which one of these is an amino group?

A) NH2

Which of the functional groups behaves as a base?

A) NH2 *the electronegativity of nitrogen means that amino groups tend to pick up hydrogen ions

When three phosphate groups are covalently attached to adenosine, __________ is formed.

ATP

Carbonyl (C=O): _________ if oxygen is at the end of hydrocarbon

Aldehyde

Isomers are compounds with the same molecular formula but different structural arrangements. (This alters the chemical and physical properties of the compounds)

HYDROCARBON ISOMERS

Which of the following are properties of hydrocarbons?

Hydrophobic, nonpolar, and a good source of stored energy

Creates polar compound due to electronegativity of oxygen

Hydroxyl (-OH)

Forms hydrogen bonds with water.

Hydroxyl (-OH)

Makes a compound an alcohol

Hydroxyl (-OH)

Makes molecules hydrophilic

Hydroxyl (-OH)

In the pharmaceutical industry, two enantiomers of a drug __________.

In the pharmaceutical industry, two enantiomers of a drug __________.

Describe the difference between structural isomers, cis-trans geometric isomers, and enantiomers.

Isomers have the same molecular formula. Structural isomers are different arrangements of covalent bonds. Enantiomers are mirror images of each other. Cis-trans isomers have different arrangements around a double bond.

Carbonyl (C=O): _______ if oxygen is in the middle of hydrocarbon.

Ketone

In a carbonyl group, _______ refers to carbon double bonded to an oxygen, occurring at the end of a chain a. Aldehyde b. Ketone

a. Aldehyde

Hydrocarbons are________ a. Hydrophobic b. Hydrophilic

a. Hydrophobic

How do isomers differ from one another? a. Isomers differ in molecular formulas b. Isomers differ in the arrangement or bonding of atoms c. Isomers differ in charge

b. Isomers differ in the arrangement or bonding of atoms

These molecules are _____. - cis-trans isomers (geometric isomers) - thiols - amines - structural isomers - enantiomers

structural isomers *The two molecules differ in the covalent bond relationships among their atoms.

Which functional group is not present in this molecule? - sulfhydryl - amino - carboxyl - hydroxyl

sulfhydryl

The chemical group that helps stabilize protein structure is the __________.

sulfhydryl group (-SH)

Which of these is a carboxyl group?

F) -COOH

Which of functional groups listed below behaves as an acid?

F) -COOH *By donating hydrogen ions, carboxyl groups act as an acid.

Macromolecules contain small reactive groups of atoms that have specific _________ properties and _____________.

chemical; characteristics

When a double bond joins two carbon atoms, __________ can form.

cis-trans isomers

These molecules are _____. - ATP and ADP - cis-trans isomers (geometric isomers) - enantiomers - thiols - structural isomers

cis-trans isomers (geometric isomers) *These molecules differ in how their atoms are arranged about a double bond.

Isomers can be expected to... a. Have the same molecular formula b. Have different properties c. Have a different 3D representation d. All of the above

d. All of the above

L-dopa is used to treat _____. a. Marfan's syndrome b. muscle sprains c. Alzheimer's disease d. Parkinson's disease e. laryngitis

d. Parkinson's disease

acts as an acid

carboxyl

Acts as a base

Amino (-NH2)

Very important in proteins

Amino (-NH2)

Which of these is a phosphate group?

B) P=O-O-O-O

Which of these groups plays a major role in energy transfer?

B) P=O-O-O-O *Phosphate groups are a component of ATP.

Biologically important chemical groups include all of the following except __________.

Biologically important chemical groups include all of the following except __________.

Which of these is a carbonyl group?

C) C=O *This is a carbonyl group.

Visualize the structural formula of each of the following hydrocarbons. Which hydrocarbon has a double bond in its carbon skeleton? - C2H2 - C2H4 - C2H6 - C3H8

C2H4

differ in spatial arrangement around a double bond

CIS-TRANS ISOMERS (ALSO CALLED GEOMETRIC ISOMERS)

Which element is always associated with organic chemistry?

Carbon

methyl (-CH3)

Carbon bonded to 3 hydrogens (Bond occurs in ring structure and in macromolecules such as DNA)

PHOSPHATE (OPO3)

Carbon has a bond to one oxygen of a phosphate group

Sulfhydryl (-SH)

Carbon has a bond to sulfur and a bond to hydrogen

Carboxyl (-COOH)

Carbon has double bond to oxygen & single bond to OH

Which of these is a hydroxyl group?

D) OH-

Which of these functional groups is characteristic of alcohol?

D) OH- *Hydroxyl groups are characteristic of alcohol.

Which of these groups is characteristic of thiols?

E) -SH *Thiols are characterized by the presence of a sulfhydryl group.

Two enantiomers of a drug have different effects •Usually only one isomer is biologically active •Differing effects of enantiomers demonstrate that organisms are sensitive to very subtle variations in molecules

ENANTIOMERS IN PHARMACEUTICALS

Which statement about isomers is correct? - Structural isomers differ in the position of double bonds within the molecule. - Enantiomers differ in biological activity. - Cis-trans isomers are mirror image isomers.

Enantiomers differ in biological activity. *Because enantiomers are mirror images of each other, working molecules distinguish the two versions by shape. Usually, one isomer is biologically active and the other is inactive.

Amino (-NH2)

Nitrogen bonded to a carbon and two hydrogens

What kind of effect does R-dopa have on Parkinson's disease? - It alleviates the symptoms. - At first it makes the symptoms worse but over the long term it alleviates the symptoms. - None. - It makes the symptoms of Parkinson's disease worse. - At first it alleviates the symptoms but over the long term it makes the symptoms worse.

None. *R-dopa has no effect on Parkinson's disease.

Carbonyl (C=O)

Oxygen double bonded to carbon

Energy currency of cells (ATP)

Phosphate

_________ group is a phosphate bonded to 4 oxygens, one of which is a double bond.

Phosphate

Atoms have different covalent bond arrangements. (Results in different compound structure)

STRUCTURAL ISOMERS

Choose the term that correctly describes the relationship between these two sugar molecules:

Structural isomers

2 -SH groups interact to stabilize protein structure

Sulfhydryl (-SH)

The carbon skeleton can vary in all of the following except __________.

The carbon skeleton can vary in all of the following except __________.

Enantiomers are molecules that _____. a. contain a carboxyl group b. are mirror images c. are isomers that differ in the covalent partnerships between their atoms d. contain an -OH group e. differ in the arrangement of their molecules about a double bond

b. are mirror images

L-dopa

biologically active ENANTIOMERS IN PHARMACEUTICALS

D-dopa

biologically inactive ENANTIOMERS IN PHARMACEUTICALS

Which of the following types of isomers are mirror images of each other? a. Structural b. Geometric c. Enantiomer

c. Enantiomer

Which of the following function groups will make a molecule hydrophilic? a. Sulfhydryl b. Methyl c. Hydroxyl d. Amino

c. Hydroxyl

List the functional groups in the above molecule. a. Amine, aldehyde b. Methyl, ketone, sulfhydryl c. Hydroxyl, ketone, amine, carboxyl d. Aldehyde, ketone, methyl

c. Hydroxyl, ketone, amine, carboxyl

Which of the following functional groups is important for energy? a. Carboxyl b. Hydroxyl c. Phosphate d. Sulfhydryl

c. Phosphate

What differs among isomers of the same molecule? a. Number of protons b. Number of neutrons c. The arrangement of the molecules d. The molecular formula

c. The arrangement of the molecules

Molecules that contain only carbon and hydrogen are __________.

called hydrocarbons

Cis-trans isomers (geometric isomers) are molecules that _____. - differ in the arrangement of their atoms about a double bond - are isomers that differ in the covalent partnerships between their atoms - are mirror images - are isomers in which one of the molecules contains an amino group and the other contains a phosphate group - differ in their molecular formulas

differ in the arrangement of their atoms about a double bond

How can carbon chains vary? a. By a single, double, or triple bond b. Ring structures c. Length d. Carbon chains can be branched or linear e. All of the above

e. All of the above

These molecules are _____. - thiols - cis-trans isomers (geometric isomers) - structural isomers - R-dopa and L-dopa - enantiomers

enantiomers

ENANTIOMERS

isomers that are mirror images of each other (Non-superimposable)

The number and arrangement of functional groups give each molecule __ ___ ___.

its unique property

Affects gene expression and Affects shape and function of male and female sex hormones

methyl (-CH3)

The chemical group that is involved in regulating DNA is the __________.

methyl group (-CH3)

Enantiomers are __________.

mirror-image isomers of a molecule

This pair of molecules are _____. - cis-trans isomers (geometric isomers) - not isomers - enantiomers - identical - structural isomers

not isomers

Structural isomers have __________.

the same molecular formula but different covalent arrangements of their carbon skeletons

Organic chemistry is currently defined as

the study of carbon compounds

Chemical groups are significant because __________.

they contribute to the molecular shape of a molecule and its unique properties