Ch 5 (Part 2) Mastering Biology

A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be composed of A) 120 thymine and 120 adenine molecules. B) 120 cytosine and 120 thymine molecules. C) 120 adenine and 120 cytosine molecules. D) 120 adenine and 120 uracil molecules. E) 120 guanine and 120 thymine molecules.

A

A hydrophobic amino acid R group (side group) would be found where in a protein? A) on the inside of the folded chain, away from water B) only at one end of a protein chain C) forming hydrogen bonds with other R groups D on the outside of the folded chain, in the water E) forming a peptide bond with the next amino acid in the polypeptide chain

A

One of the primary functions of RNA molecules is to A) function in the synthesis of proteins. B) act as a pattern or blueprint to form DNA. C) make a copy of itself, thus ensuring genetic continuity. D) transmit genetic information to offspring. E) form the genes of higher organisms.

A

The flow of genetic information in a cell goes from _____. A) DNA to RNA to protein B) DNA to ribosomes to RNA C) protein to RNA to DNA D) DNA to RNA to glucose E) DNA to lipid to protein

A

The structural level of a protein least affected by a disruption in hydrogen bonding is the A) primary level. B) quaternary level. C) tertiary level D) secondary level. E) All structural levels are equally affected.

A

What type of amino acid is Glutamic acid? (R group is negatively charged)

Acidic

Acidic amino acids have what type of R groups?

Acidic, negatively charged (These molecules are highly soluble in water)

Wat structures are in both DNA and RNA?

Adenine, cytosine, guanine, and phosphate

What is the term used for a protein molecule that assists in the proper folding of other proteins? A) enzyme protein B) chaperonin C) renaturing protein D) denaturing protein E) tertiary protein

B

What maintains the secondary structure of a protein? A) hydrophobic interactions B) hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond C) peptide bonds D) disulfide bonds E) hydrogen bonds between the R groups

B

Which level of protein structure do the α helix and the β pleated sheet represent? A) primary B) secondary C) tertiary D) quaternary E) primary, secondary, tertiary, and quaternary

B

What type of amino acid is Arginine? (R group is positively charged)

Basic

What type of amino acid is Lysine? (R group is positively charged)

Basic

Basic amino acids have what type of R groups?

Basic, positively charged (These molecules are highly soluble in water)

Where does a peptide bond occur?

Between the C of a C=O (carboxyl) and the N of a N-H (amine)

Identify three possible components of a DNA nucleotide. A) cytidine, phosphate group, ribose B) deoxyribose, phosphate group, uracil C) deoxyribose, phosphate group, thymine D) cytosine, phosphate group, ribose E) adenine, phosphate group, ribose F) guanine, phosphate group, ribose

C

If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence A) 5'UGCAAU3'. B) 3'UAACGU5'. C) 5'TGCAAT3'. D) 5'TAACGT3'. E) 5'UAACGU3'.

C

Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNA? A) 5´-AGCT-3´ with 5´-TCGA-3´ B) 5´-GCGC-3´ with 5´-TATA-3' C) 5´-ATGC-3´ with 5´-GCAT-3´ D) All of these pairs are correct. E) 5´-purine-pyrimidine-purine-pyrimidine-3´ with 3´-purine-pyrimidine-purine-pyrimidine-5´

C

In a normal cellular protein, where would you expect to find a hydrophobic amino acid like valine? A) in the transmembrane portion interacting with lipid fatty acid chains B) anywhere in the protein, with equal probability C) in the interior of the folded protein, away from water D) in the interior of the folded protein, away from water, or in a transmembrane portion interacting with lipid fatty acid chains E) on the exterior surface of the protein, interacting with water

D

The tertiary structure of a protein is the A) overall protein structure resulting from the aggregation of two or more polypeptide subunits. B) order in which amino acids are joined in a polypeptide chain. C) bonding together of several polypeptide chains by weak bonds. D) unique three-dimensional shape of the fully folded polypeptide. E) organization of a polypeptide chain into an α helix or β pleated sheet.

D

What proteins are part of the immune system and are called "antibodies" that bind to invaders, such as viruses, to mark the foreign objects for destruction?

Defensive proteins

What structures are exclusively in DNA?

Deoxyribose and thymine

DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase? A) The purines would be separated from the deoxyribose sugars. B) The pyrimidines would be separated from the deoxyribose sugars. C) All bases would be separated from the deoxyribose sugars. D) The two strands of the double helix would separate. E) The phosphodiester bonds between deoxyribose sugars would be broken.

E

Defensive proteins are manufactured by the _____ system. A) nervous B) cardiovascular C) integumentary D) digestive E) immune

E

If cells are grown in a medium containing radioactive 35S, which of these molecules will be labeled? A) nucleic acids B) phospholipids C) both proteins and nucleic acids D) amylose E) proteins

E

Which of the following statements best summarizes the differences between DNA and RNA? A) The bases in DNA form base-paired duplexes, whereas the bases in RNA do not. B) DNA contains the base uracil, whereas RNA contains the base thymine. C) DNA encodes hereditary information, whereas RNA does not. D) DNA encodes hereditary information, whereas RNA does not; the bases in DNA form base-paired duplexes, whereas the bases in RNA do not; and DNA nucleotides contain a different sugar than RNA nucleotides. E) DNA nucleotides contain a different sugar than RNA nucleotides.

E

Which of these does NOT contain a structural protein? A) tendons B) ligaments C) muscles D) spider silk E) ovalbumin

E

What changes the rate of a chemical reaction without itself being changed into a different molecule in the process, and promote and regulate virtually all chemical reactions in cells?

Enzymes

What proteins bind to DNA in particular locations and control whether or not certain genes will be read, allowing cells to become specialized for different functions and respond to changes in their surroundings?

Gene regulatory proteins

What type of amino acid is Alanine? (R group is CH3)

Neutral nonpolar (CH3 is symmetrical in charge)

What type of amino acid is Valine? (R group is CH with a single bonded CH3 and another single bonded CH3)

Neutral nonpolar (made up of Cs and Hs, symmetrical in charge)

Wat type of amino acid is Phenylalanine? (R group is CH2-Ring with 3 single bonds and 3 double bonds)

Neutral nonpolar (symmetrical in charge)

What type of amino acid is Methionine? (R group is CH2-CH2-S-CH3)

Neutral nonpolar (symmetrical in charge)

What type of amino acid is Tryptophan? (R group is CH2-(2 rings containing an N), with N-H on the end)

Neutral nonpolar (symmetrical in charge)

What type of amino acid is Proline? (R group is made up of Ch2-Ch2-H2C and connects back to H2N)

Neutral nonpolar (symmetrical in charge, made up of all H and C)

What type of amino acid is Threonine? (R group is HCOH-CH3)

Neutral polar (HCOH makes it unsymmetrical in charge)

What type of amino acid is Asparagine (R group has a CH2-C with a double bonded O and a single bonded NH2)

Neutral polar (O makes it unsymmetrical in charge)

What type of amino acid is Glutamine? (R group has a CH2-CH2-C with a double bonded O and a single bonded NH2)

Neutral polar (O makes it unsymmetrical in charge)

What type of amino acid is Serine? (R group is CH2-OH)

Neutral polar (OH makes it unsymmetrical in charge)

What type of amino acid is Tyrosine? (R group is CH2-(ring with 3 single bonds and 3 double bonds)-OH

Neutral polar (OH makes it unsymmetrical in charge)

Neutral nonpolar amino acids have what type of R groups?

Nonpolar, uncharged (Most of these amino acids are not water soluble)

Neutral polar amino acids have what type of R groups?

Polar, uncharged, have a dipole moment (These molecules are generally water soluble)

What binds to signal molecules and can emit second messengers which trigger changes inside a cell, and are therefore an important link in the system of communication among cells?

Receptor molecules

What structures are exclusively in RNA?

Ribose and uracil

What proteins detect environmental changes such as light, and respond by emitting or producing signals that call for a response?

Sensory proteins

What proteins include hormonal proteins that help coordinate an organism's activities by acting as signals between cells?

Signal proteins

What proteins stockpile building components that cells can use to make other proteins?

Storage proteins (Ovalbumin, the main substance in egg white, serves as a storage protein for developing chick embryos)

Which proteins shape cells and anchor cell parts, serve as tracks along which cell parts can move, and bind cells together to create units such as muscles, ligaments, and tendons?

Structural proteins

How do ribose and deoxyribose differ in appearance of molecule?

The bottom of the ribose molecule has 2 OHs, the deoxyribose has 1 OH and 1 H

What do pyrimidines look like?

They have 1 ring structure

What do purines look like?

They have 2 ring structures

What proteins carry molecules from place to place?

Transport proteins

What does phosphate look like?

a P with 3 single bonded negative Os and one double bonded O

What are the most complicated molecules known?

proteins