Bsc1010 ch 5

The four main categories of large biological molecules present in living systems are _____.

...

Sugars are molecules that have_______ C:H:O and are called_______.

A 1:2:1 ratio of ; carbohydrates

The peptide bond is

A covalent bond joining amino acids together to form a polypeptide

Protein molecules are polymers (chains) of __________.

Amino acid molecules

Proteins are polymers of _____.

Amino acids

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

Amylose

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

An oxygen

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

As a component of animal cell membranes

Which part of an amino acid is always acidic? -Amino functional group -Carboxyl functional group -Side chain ("R group") -None of the above

Carboxyl functional group (The carboxyl group (COOH) contains two oxygen atoms that tend to pull electrons away from the hydrogen atom, so this group tends to lose a proton and is acidic)

Which of the following is a polymer?

Cellulose

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

Cellulose: structural component of plant cell walls

The molecule with four fused rings that is found in animal membranes and is the precursor of vertebrate sex hormones is __________.

Cholesterol

Palm oil and coconut oil are more like animal fats than are other plant oils. Because they _____ than other plant oils, they may contribute to cardiovascular disease.

Contain fewer double bonds

The type of bond that forms to join monomers (such as sugars and amino acids) into polymers (such as starch and proteins) is a(n) __________ bond.

Covalent

In living organisms, DNA exists as a __________ with the strand(s) __________.

Double helix; antiparallel

A polysaccharide that is used for storing energy and human muscle and liver cell is

Glycogen

The sex hormones estrogen, progesterone, and testosterone belong to which class of molecules?

Lipids

Generally, animals cannot digest (hydrolyze) the glycosidic linkages between the glucose molecules in cellulose. How then do cows get enough nutrients from eating grass?

Microorganisms in their digestive tracts hydrolyze the cellulose to individual glucose units.

The proper three-dimensional shape and folding of a protein is assisted by _________.

Molecules called chaperonins

Which of the following statements about monosaccharide structure is true?

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

The building blocks or monomers of nucleic acid molecules are called _____.

Nucleotides

Which monomers make up RNA?

Nucleotides

A hydrophobic amino acid R group (side group) would be found where in a protein?

On the inside of the folded chain, away from water

Which of these does NOT contain a structural protein?

Ovalbumin

The tertiary structure of a protein include all of the following interactions except ______ bonds

Peptide

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; hydrogen bonds

One characteristic shared by sucrose, lactose, and maltose is that

They are all disaccharides

Macromolecules, the molecules of life, include all of the following except __________.

Trace elements

The components of nucleic acids are __________.

a nitrogenous base, a pentose sugar, and a phosphate

Proteins are polymers of _____.

amino acids

Sugars have a(n) __________ group that interacts with a _________ group that forms ring structures when the dry molecule is placed in water.

carbonyl (-C=O); hydroxyl (-OH)

amylose

simplest form of starch, unbranched

Which of the following statements about the formation of polypeptides from amino acids is true? -The reaction occurs through the addition of a water molecule to the amino acids. -A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid. -A bond can form between any carbon and nitrogen atom in the two amino acids being joined. -Polypeptides form by condensation or hydrolysis reactions

A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid. (A hydroxyl group is removed from the carboxyl group of one amino acid and hydrogen is removed from the amino group of the other amino acid, allowing a bond to form between the two groups)

A polysaccharide that is used for storing energy in human muscle and liver cells is __________.

Glycogen

Sucrose is formed when glucose is joined to fructose by a(n) _____.

Glycosidic linkage

The subunits (monomers) in cellulose are linked together by __________.

Glycosidic linkages

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

Peptide

Which polysaccharide contains a modified monosaccharide?

Peptidoglycan

The lipids that form the main structural component of cell membranes are __________.

Phospholipids

Which polymers are composed of amino acids?

Proteins

Purines and Pyrimidines

AG and CAT

Nitrogenous bases are classified as either purines or pyrimidines. Examples of purines are __________.

Adenine and Guanine

ence, the speaker's grand finale was sautéing mealworms (insect larvae) in butter and serving them to the audience. They were crunchy (like popcorn hulls) because their exoskeletons contain the polysaccharide __________.

Chitin

Which of the following is attached to the central carbon atom in an amino acid?

R group, amino group, carboxyl group

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

True

Which of these is NOT a lipid?

RNA

Sickle-cell anemia is a disease that is caused by __________ in the __________ of the protein.

Single cell amino acid change; primary structure

Which of the following statements about DNA structure is true?

The nucleic acid strands in a DNA molecule are oriented antiparallel to each other.

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

True (Enzymes in the digestive tract break down food molecules, which is a process that occurs by hydrolysis.)

In a dehydration synthesis reaction, __________ is always formed as a by-product of the reaction.

Water

A dehydration reaction (or condensation reaction) is the process in which _____.

Water molecules are produced as a polymer is formed from monomers

A shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture

DNA