Bio 101: Chapter/Lab 3

How many hydrogen atoms can be attached to carbon B? 2 1 4 3

1

How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?

10

If a strand of DNA has the nitrogen base sequence 5'-ATTTGC-3', what will be the sequence of the matching strand?

3'-TAAACG-5'

How many electron pairs does carbon share in order to complete its valence shell?

4

If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?

75 100 nucleotide pairs are a total of 200 nucleotides. Because of base pairing, if there are 25 adenine there must also be 25 thymine. This leaves 200-50 = 150 nucleotides to be divided evenly between guanine and cytosine.

How many molecules of water are needed to completely hydrolyze a polysaccharide that is 10 monomers long?

9

Upon chemical analysis, a particular polypeptide was found to contain 100 amino acids. How many peptide bonds are present in this protein?

99

Which of the following statements about the formation of polypeptides from amino acids is true?

A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.

The two strands of a DNA double helix are held together by _____ that form between pairs of nitrogenous bases.

A) hydrogen bonds Nitrogenous base pairs are joined by hydrogen bonds.

Which of the functional groups behaves as a base?

A, the electronegativity of nitrogen means that amino groups tend to pick up hydrogen ions

Select the statement that is incorrect.

All carbohydrates have the general formula

Which complex carbohydrate contains only a-1,4-glycosidic linkages?

Amylose

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

B, phosphate groups are a component of ATP

Which bond is a peptide bond?

C

Which of these is a carbonyl group?

C This is a carbonyl group.

The element present in all organic molecules is

Carbon

Which part of an amino acid is always acidic?

Carboxyl functional group

Which of the following complex carbohydrates is listed with its correct function?

Cellulose: structural component of plant cell walls

Variations in the reactive properties of different organic molecules are most closely associated with _____. the presence or absence of double bonds the number of carbon atoms comprising the molecule's skeleton the orientation of the carbon skeleton, as either ringed or linear the presence or absence of functional groups

D

Which of these functional groups is characteristic of alcohol?

D

Which of these is a carboxyl group?

F This is a carboxyl group

Which of functional groups listed below behaves as an acid?

F, by donating hydrogen ions, carboxyl groups acts as an acid

Which of the following is true of cellulose?

It is a major structural component of plant cell walls

Which of the following statements about monosaccharide structure is true?

Monosaccharides can be classified according to the spatial arrangement of their atoms.

Which one of these is an amino group?

NH2 (A)

Which of these is a hydroxyl group?

OH- (D)

Which of these is a phosphate group?

P=O-O-O-O (B)

Which polysaccharide contains a modified monosaccharide?

Peptidoglycan Submit

Which of these is NOT a lipid?

RNA

The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. What is the result of adding hydrogens to vegetable oil?

The hydrogenated vegetable oil stays solid at room temperature.

Which of the following is true of both starch and cellulose?

They are both polymers of glucose.

Which of the following statements is true for the class of biological molecules known as lipids?

They are insoluble in water.

Why are human sex hormones considered to be lipids?

They are not soluble in water.

Which of the following is true regarding saturated fatty acids?

They are the principal molecules in lard and butter.

Normal hemoglobin is a tetramer, consisting of two molecules of β-globin and two molecules of α-globin. In sickle-cell disease, as a result of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assemble into large fibers. Based on this information alone, we can conclude that sickle-cell hemoglobin exhibits

altered primary structure and altered quaternary structure; the secondary and tertiary structures may or may not be altered.

Proteins are polymers of _____.

amino acids

A function of cholesterol that does not harm health is its role _____.

as a component of animal cell membranes

Which chemical group can act as an acid?

carboxyl

Which two functional groups are always found in amino acids?

carboxyl and amino

Plant cell walls consist mainly of _____.

cellulose

Which of the following polymers contain nitrogen?

chitin

All of the following contain amino acids except

cholesterol

A carbon atom is most likely to form which of the following bonds with other atoms?

covalent

What is the chemical reaction mechanism by which cells make polymers from monomers?

dehydration reactions

What is another name for a condensation reaction?

dehydration synthesis

Which of these groups is characteristic of thiols?

e, thiols are characterized by the presence of a sulfhydryl group

Which of these molecules is not formed by dehydration reactions?

fatty acids

One of the primary functions of RNA molecules is to

function in the synthesis of proteins.

Which of the following is not a polymer?

glucose

Humans can digest starch but not cellulose because

humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.

The secondary structure of a protein results from _____.

hydrogen bonds

What is the name of the process during which a bond between two monomers is broken?

hydrolysis

Defensive proteins are manufactured by the _____ system.

immune

An atom of iron has the atomic number 26. This means that it has 13 electrons, 26 protons, and 26 neutrons. it has 26 protons and 26 electrons. it has 13 neutrons, 13 protons, and 13 electrons. it has 52 protons and 52 electrons.

it has 26 protons and 26 electrons. The atoms of a particular element have a unique number of protons in their nuclei, and this number is called the atomic number. Unless otherwise indicated, an atom is neutral in electrical charge, which means that its protons must be balanced by an equal number of electrons. Therefore, since the atomic number tells us the number of protons, it also tells us the number of electrons in an electrically neutral atom.

A compound contains hydroxyl groups as its predominant functional group. Which of the following statements is true concerning this compound?

it should dissolve in water

Which molecule is not a carbohydrate?

lipid

Which monomers make up RNA?

nucleotides

Which of these is rich in unsaturated fats?

olive oil Olive oil is a plant oil, and most plant oils are rich in unsaturated fats.

Which of these does NOT contain a structural protein?

ovalbumin

Which of the following is not attached to the central carbon atom in an amino acid?

oxygen

What type of bond joins the monomers in a protein's primary structure?

peptide

Tertiary structure is NOT directly dependent on _____.

peptide bonds

A nucleotide is composed of a(n) _____.

phosphate group, a nitrogen-containing base, and a five-carbon sugar

Which polymers are composed of amino acids?

proteins

Arrow D is indicating a _____ protein.

receptor

This figure is an example of a(n) _____.

saturated fat The fatty acid tails lack double bonds.

Which level of protein structure do the α helix and the β pleated sheet represent?

secondary

Some regions of a polypeptide may coil or fold back on themselves. This is called _____, and the coils or folds are held in place by _____.

secondary structure ... hydrogen bonds

An atom has four electrons in its valence shell. What type(s) of covalent bonds is it capable of forming with oxygen? single and double bonds double bonds only it cannot form covalent bonds with oxygen single bonds only

single and double bonds The number of electrons in an atom's valence shell determines its bonding capacity. The type of covalent bond an atom with four valence electrons is capable of forming with oxygen will be limited by oxygen. Oxygen has six valence electrons, and can form two covalent bonds (one double bond or two single bonds) to complete its valence shell.

Arrow A is indicating a(n) _____ protein.

structural

Based on the electron configuration of the elements in the figure, which would exhibit a chemical behavior most like that of oxygen? sulfur phosphorus carbon nitrogen

sulfur

The complexity and variety of organic molecules is due to

the chemical versatility of carbon atoms

A nutritional supplement developed for athletes is shown to contain only carbon, hydrogen, and oxygen. Based on these data, you may safely conclude that:

the food may contain carbohydrates and lipids, but not protein. (no N?)

A nutritional supplement developed for athletes is shown to contain only carbon, hydrogen, oxygen, nitrogen, and sulfur. Based on these data, you may safely conclude that:

the food may contain carbohydrates, lipids, and protein.

Which of the following is an example of a hydrolysis reaction?

the reaction of a fat, forming glycerol and fatty acids with the consumption of water

Which of the following is not a monomer/polymer pairing? amino acid/protein ribonucleotide/RNA triglyceride/phospholipid bilayer monosaccharide/polysaccharide deoxyribonucleotide/DNA

triglyceride/phospholipid bilayer

True or false? Enzymes in the digestive tract catalyze hydrolysis reactions.

true

True or false? Peptidoglycan is a polysaccharide found only in bacteria.

true

The tertiary structure of a protein is the

unique three-dimensional shape of the fully folded polypeptide