BIO EXAM 1

In which of the following cellular processes is RNA involved? -splicing -All of these choices are correct. -transcription and translation -translation -transcription

All of these choices are correct

Which of the following is the BEST description of mutations? -They occur randomly. -They do not affect an organism. -All of the answer options are correct. -They arise in order to harm an organism. -They arise in order to benefit an organism.

They occur randomly.

Which of the following is NOT needed for DNA replication?

ribosomes

Translation is the process by which:

ribosomes synthesize protein from information in an RNA molecule.

Which of the following types of organisms are based on cellular life? -All living organisms are based on cells. -yeast -animals -plants -bacteria

All living organisms are based on cells.

Why do data on observable mutant phenotypes underestimate the actual frequency of mutation? (Select all that apply.) -Some mutations in protein-coding regions of the genome are synonymous mutations. -Most mutations result in death of the individual or an inability to reproduce. -Many mutations are in noncoding regions of the genome.

-Some mutations in protein-coding regions of the genome are synonymous mutations. -Many mutations are in noncoding regions of the genome.

In the standard genetic code (Table 4.1, shown below), how many amino acids have codons that allow synonymous mutations in the second position?

0

the epithelial cells in the skin of an animal have 24 chromosomes. How many chromosomes are present in the gametes of this animal?

12

How many chromosome pairs are there in a normal human genome?

23

In a DNA strand, successive nucleotides are linked by:

3'-5' phosphodiester bonds

A template DNA strand contains 30% A, 20%T, 27% G, and 23% C. The RNA transcript contains:

30% U, 20% A, 27% C, and 23% G

A template DNA strand contains the sequence 5'-ATGCTGAC-3'. The corresponding sequence in the RNA transcript is:

5'-GUCAGCAU-3'

During DNA replication in a cell, RNA primase synthesizes a primer that is complementary to the region in the sequence below shown in bold. 5'CACAGCAGAAACCTACAACTCATG-3' What is the primer sequence?

5'GUUGUAGGUUUC-3'

Which one of the following can contribute to a protein's tertiary structure? -hydrogen bonding -ionic bonding -covalent bonding -All of the other answer options are correct. -van der Waal's forces

All of the answers are correct

In a diploid individual, one chromosome carries A and B genes, and the homologous chromosome carries different forms (alleles) of these same genes, a and b. If there is a single crossover between these two genes involving non-sister chromatids during metaphase I of meiosis, the resulting four gametes are:

AB, Ab, aB,Ab

What CORRECTLY describes the complementary base pairing of adenine in both DNA and RNA?

Adenine pairs with thymine in DNA and with uracil in RNA.

Proteins can be used for which cellular roles?

Cell communication structural support cell signaling biological catalysts

Which of the following enzymes is the first to bind to the DNA sequences at the origin of replication? -DNA polymerase -DNA ligase -single-strand binding protein -DNA primase -DNA helicase

DNA Helicase

The enzyme responsible for joining Okazaki fragments together during DNA replication is

DNA Ligase

What is the central dogma?

DNA is transcribed into RNA, which is translated into protein.

The enzyme responsible for proofreading a growing DNA strand and for replacing mistakes:

DNA polymerase

The enzyme responsible for replacing RNA primers with DNA is a type of:

DNA polymerase

What is the order of processes that support the central dogma?

DNA replication, transcription, translation

A mutation in _____ results in a change in _____ that sometimes produces a(n) _____ with altered structure and function.

DNA; RNA; protein

Which of the following is NOT a characteristic of meiotic cell division?

Daughter cells are genetically identical

Most proteins retain metabolic activity when denatured. (True or False)

False

You have learned that mutations can occur in DNA sequences. Are all mutations deadly?

No, some mutations can be beneficial

Which mutations in an animal somatic cell would be inherited by the next generation? -point mutations -deletions -None of the other answer options is correct. -synonymous mutations

None of the options are correct

How many chromosomes are found in a single human cell at the end of each of the following stages of mitosis?

Prophas-46 Metaphase-46 Anaphase-92 Telophase-92

In which phase of mitosis do chromosomes condense?

Prophase

When in the cell cycle would you find sister chromatids?

S and G2

Which of the following is true about the structure of a double-stranded DNA molecule?

The diameter of a DNA molecule is the same along its entire length due to the specific complementary base pairing of the DNA nucleotides.

The language of nucleic acids is converted to the language of amino acids during the process known as

Translation

Any heritable change in the genetic material is _____.

a mutation

An intron is:

an RNA sequence that is removed during the processing of an RNA molecule in the nucleus.

In which phase of mitosis do sister chromatids separate?

anaphase

During what step in meiosis do the daughter cells become haploid?

anaphase I

How does meiosis generate genetic diversity?

both crossing over and random alignment at metaphase I

Deletions that eliminate a multiple of three nucleotides can:

delete amino acids in a polypeptide chain

A zygote is:

diploid

A major difference between eukaryotic cells and prokaryotic cells is that:

eukaryotic cells have a nucleus and prokaryotic cells do not.

A human cell with a total of 23 chromosomes is:

haploid

The fact that DNA replication occurs in virtually the same way in all organisms reflects:

its origin early in the history of life

In which phase of mitosis do chromosomes line up in the middle of the cell?

metaphase

Consider the single methionine codon 5′-AUG-3′ in the standard genetic code. Can a single base change in this codon create a synonymous mutation? Can a single base change in this codon create a stop codon?

no and no

Point mutations that cause amino acid replacements are called

nonsynonymous (missense) mutation

In a double-stranded DNA molecule, the strands are said to be antiparallel because:

one strand runs 5' to 3' and the other 3' to 5'.

At some point in their life cycle, all cells have a _____, whereas not all cells have a(n) _____

plasma membrane; nuclear membrane

The two molecules of double-stranded DNA in a replicated chromosome are called:

sister chromotids

Deoxyribonucleic acid is used for:

storage of info transmission of info

A point mutation that causes no change in the amino acid sequence of a protein is called a

synonymous (silent) mutation.

What brings amino acids to the ribosome for use in translation?

tRNA

What would happen to the variation between organisms in a population if their DNA polymerase did NOT have a proofreading function?

the amount of variation would increase

What feature of double-stranded DNA makes it necessary to have a leading strand and a lagging strand during replication?

the antiparallel orientation of the strands

Miotic cell division is considered asexual because:

the daughter cells receive DNA from one parent cell, and the daughter cells are genetically identical

What is the function of the centromere?

to attach the sister chromatids to each other

_____ relieves the tension on the double helix during DNA replication.

topoisomerase

Which of the cellular processes occurs in the nucleus of a eukaryote?

transcription and RNA processing

Which of the following processes occur in the cytoplasm of eukaryotic cells? -DNA replication, transcription, and translation -transcription and translation -DNA replication only -translation only -DNA replication and transcription

translation only

Sister chromatids are BEST described as two DNA molecules that have:

virtually identical sequences of nucleotides.