BIO EXAM 2 Review

Polar and nonpolar R-groups repelling one another, Ionic bonds between charged R-groups, Disulfide bridges between cysteine amino acids, H-bonding between distant polar R-groups

Polar and nonpolar R-groups repelling one another, Ionic bonds between charged R-groups, Disulfide bridges between cysteine amino acids, H-bonding between distant polar R-groups

Tertiary protein structure results from (choose all correct):

• Polar and nonpolar R-groups repelling one another.

• H-bonding between any polar R-groups.

• Ionic bonds between charged R-groups.

• Disulfide bridges between cysteine amino acids.

• Denaturation proteins.

• H-bonding between the polar R-groups of every fourth amino acid.

• H-bonding between distant polar R-groups.

2 protein structure

Alpha helices and beta pleated sheets are examples of (choose all correct):

• 3˚ protein structure

• 1˚ protein structure.

• 4˚ protein structure.

• 2˚ protein structure.

the R-groups it has

The differences among proteins derive from

bacteria

Cytoskeletons are found in all but which of the following types of cells?

Water is consumed in these reactions.

Which of these are not true of condensation reactions, or dehydration synthesis?

When the cell is resting.

When do you predict that a cell will contain the lowest proportion of actin?

microtubule

From the movie "Inner Life of a Cell" we watched on Friday, along what structure is the motor protein kinesin appearing to "walk"?

The part of the protein that is embedded in the membrane will mostly be polar on its inner surfaces, The parts of the protein external to the membrane will mostly be polar, The part of the protein embedded in the membrane will mostly be nonpolar on its outer surfaces

Suppose a large protein is embedded in a cell's plasma membrane to facilitate water diffusing through the plasma membrane. Predict the properties of the specific parts of the protein shown in the model figure. Choose all correct.

• The part of the protein that is embedded in the membrane will mostly be polar on its inner surfaces.

• There is no way to predict the properties of a large protein.

• The parts of the protein external to the membrane will be nonpolar.

• The parts of the protein external to the membrane will mostly be polar.

• The part of the protein embedded in the membrane will mostly be nonpolar on its outer surfaces.

• The parts of the protein embedded in the membrane could be either polar or nonpolar in all regions.

When ATP dephosphorylates, it gives kinesin energy to walk

Molecules have no inherent intention except to occupy the lowest possible energy state. What, then, explains the appearance of the motor protein kinesin "walking" (from "Inner Life of a Cell")?

dehydration synthesis, a peptide bond

The reaction that polymerizes polypeptides is (choose all correct):

• dehydration synthesis

• hydrolysis

• different than carbohydrates

• the same as for carbohydrates

• a peptide bond

the mRNA will not be affected

The following is a eukaryotic DNA sequence. The coding sequence of the gene is in bold and italicized, and the promoter is underlined.

DNA: 5'   T C T A A G G* A A T T A T A A T A C G A C C ... A T G A T G T A C G C A T A A A C G T   3'

A mutation occurs in which a base (A) is inserted into the DNA sequence after the G, at the position marked with an asterisk (*), before transcription begins. How will this alteration influence the mRNA product?

the nucleus

In eukaryotes, RNAs are transcribed where?

alanine, serine, histidine

Suppose a sequence of mRNA reads 5' GCAUCCCAC 3'. What is the sequence of amino acids?

nonsense mutation

A single nucleotide change due to mutation in DNA may lead to a change in amino acid composition or sequence in a polypeptide, affecting the protein structure and function. Which of the following point mutations will result in a smaller polypeptide?

tRNA

Carries the correct amino acid to the site of protein synthesis in the ribosome.

rRNA

Ensures the proper alignment of other RNAs and ribosome during protein synthesis and catalyzes peptide bond formation between amino acids

mRNA

Used by the ribosome to direct synthesis of protein it encodes.

each three-nucleotide segment conveys information about a single amino acid.

Two scientists, Crick and Brenner, found that when three extra sequential nucleotides were inserted in the middle of a gene, the resulting protein was more similar to the original protein than when they inserted only one or two extra nucleotides. Their best conclusion from this is:

peroxisomes, mitochondria

All organelles are connected to the eukaryotic endomembrane system except which of these? Choose all correct.

smooth endoplasmic reticulum

A rare inherited disorder makes it difficult for some people's muscles to maintain adequate amounts of calcium ions (Ca²⁺) in their muscles. Which cell organelle is malfunctioning in the muscles of these people?

intracellular domain III, transmembrane domain V

Use the following diagram of mutations in the rock pocket mouse Mc1r gene to predict: which mutation is likely to have a large effect on how the Mc1r protein functions? Choose one or more.

arginine to tryptophan; large

This question refers to the rock pocket mice transcription and translation handout, and assumes that you completed the transcription and translation tables from C16 post for intracellular domain III and transmembrane domain V.

At intracellular domain III, the amino acid substitution is _____. This is likely to have a _____ consequence for how the Mc1r protein functions in a mouse. 

uncondensed; chromatin

During the G1 phase of interphase, DNA exists in a/an ____ state in the nucleus. This configuration of DNA is termed _____.

a region of a chromosome to which kinetochores will bind.

The centromere is:

G1

You are studying the cell cycle by measuring the amount of DNA in cells. You collect the following data (pg = picograms, or 1x10^-15 grams).

Phase 1 must be:

RNA primers.

Primase synthesizes

DNA polymerase can only add nucleotides to the free 3' end.

Why are new DNA strands elongated only in the 5' to 3' direction?

22%

Suppose a sample of DNA is fractionated to its bases, and found to contain 28% guanine. What percentage of the remaining bases is adenine?

phosphoryl

The functional group found at the 5' end of nucleic acids is:

hydrogen.

The type of bond that binds the two strands of DNA together is

the leading strand is replicated continuously, and the lagging strand is replicated in segments.

The main difference between replication of a leading and lagging strand of DNA is:

The leading strand is synthesized same direction as the replication fork, and the lagging strand is opposite

How do leading and lagging strands differ?

16; 32

Use your mitosis table from the last 4 slides from the C21 "post" deck to answer the following question. A diploid kangaroo has eight homologous chromosomes. In metaphase of mitosis, one of the kangaroo's cells will have ____ chromosomes, and ____ chromatids. 

128; 0

Use your mitosis tables to answer the following question. The diploid American badger has 32 homologous chromosomes. In telophase of mitosis, one of the badger's cells will have ____ chromosomes, and ____ chromatids. 

2

During prophase of mitosis, one chromosome consists of how many double-helix molecules of DNA? (Hint: draw!)

during the S phase

During the cell cycle, chromosomes are duplicated:

prophase

A new chemotherapeutic drug inhibits spindle fiber polymerization. In what phase will mitosis be arrested? Mitosis will proceed no further than:

chromatin, chromosome

The figure below illustrates the packaging of DNA.  There are two correct terms to characterize structure A. What are they?

karyokinesis

Which eukaryotic cell-cycle event is missing in binary fission performed by prokaryotes?

S-phase

A new drug inhibits tubulin polymerization in centrioles. Cells treated with this drug would arrest (stop) the cell cycle in:

centromeres

In the model of a nucleus below, the black ovals represent:

at prophase

A new chemotherapeutic drug has been developed that blocks the formation of kinetochore proteins. At what phase of mitosis will the cell cycle be arrested?

glycine increases the flexibility of the peptide backbone.

Which of the statements is true regarding glycine?

the side chain

Which component of an amino acid differs from one amino acid to another?

carry vesicles along a microtubule within a cell in a minus-to-plus direction

Kinesin motor proteins use the energy of ATP to:

water accumulation in a cell with a rigid cell wall

Turgor pressure is the result of:

the addition of sugars to lipids or proteins

What is glycosylation?

channel protein

A nuclear pore is most similar to a:

transformation

When DNA or genetic information is passed between bacteria (and bacteria take up this material from their surrounding environment), this process is referred to as:

1’

To what carbon(s) of the deoxyribose sugar is the base attached?

AT require less energy to separate than CG

Promoters of many genes have mostly adenines and thymines. What is the most likely reason for this high proportion of adenines and thymines?

operon, polycistronic

An _____ is a group of functionally related gene transcribed as a ___________ mRNA from a single promoter to a single terminator.

The primary transcript would likely be less stable and the transport from the nucleus to the cytoplasm would be affected.

Imagine that a eukaryotic cell carries a mutation that causes the poly(A) tail to rarely be added to the primary transcripts. What would be the result of such a mutation?

W

Which labeled arrow in this figure could represent the exception to the centrla dogma that occurs in some viruses such as HIV (the virus that causes AIDS)?

as many as the number of electrons, protons, and neutrons in the universe

How many different sequences of 133 nucleotides are possible?

In DNA replication, the ribose lacks a 2’ hydroxyl group

ATP, the ubiquitous molecule invovled in providing energy for many cellular functions, is a nucleotide that includes ribose as its sugar component. ATP is also the monomer used when adding an A to the growing strand during DNA replication. How do these molecules differ?

DNA uracil glycosylase

Which enzyme is responible for initiating certain types of base excision repair?

all are correct

Which of the steps in prokaryotic binary fission is correct?

• The cell continues to grow outward symmetrically, seperating the two chromosomes

• DNA is replicated bidirectionally from a single point on the circular chromosome

• The cell wall material is laid down at the midpoint to seperate the two daughter cells

• The two replicated chromosomes remain attached to the plasma membrane.

cytokinesis does not occur

Muscle cells in the mammalian heart are multinucleate, meaning that multiple nuclei are present in the cytoplasm of individual large cells. Predict what is different about the cell cycle in a muscle cell.

haploid

A human cell with a total of 23 chromosomes is:

away from the centrosome and toward the kinetochore

The microtubules that form the mitotic spindle extend out from the centrosome. Where would you expect to find the plus (fast-assembling) end of a spindle microtubule?

DNA damage, CDK activies not regulated, the G1/S checkpoints not functional.

How would the loss of p53 activity affect a cell?

haploid, 39

Diploid with 78 total chromosomes in somatic cells. What is the ploidy and number of homologous chromosomes in a gamete?

23, 23

Number of unique chromosomes and pairs of homologous chromosomes in a human somatic cell nucleus?

anaphase

Taxol will arrest the cell in?

duplicated

at the end of interphase the chromosomes have been?

phosphate, pentose sugar, nitrogenous base

a nucleotide monomer consists of?

continuous with one another

the cells nuclear membrane and rough ER membrane are?

DNA transcription and translation rate, diffusion

what limits that largest size that cells can be?

nitrogenous base, phosphate group, 5-carbon sugar

The monomer of all nucleic acids is composed of which three subunits?

metaphase 1

Paired homologs line up in the middle of the cell during?

repairing damage, asexual reproduction, growth

Mitosis and the division of the cytoplasm are needed for?

metaphase

A new drug, A154BB has been developed for some cancers. It works by inhibiting the depolymeraization of mitotic spindle fibers, it will not proceed past?

a change in the nucleotide sequence of DNA

A mutation is

the promoter, the coding region

The includes which two of the following?

small ribosome, specific tRNA, mRNA transcript

Which three structures are involved in the initiation step of translation?

the R-group chains it has

the differences among proteins derive from

cytoskeleton, endomembrane system

Which two characteristics predict a much larger possible cell size?

topoisomerase

A scientist randomly mutates the DNA of a bacterium. She then sequences the bacteria and finds the daughters have many errors in their replicated DNA. Which enzyme had a mutation?

synaptonemal complex

Which structure below facilitates crossing over?

intiation

Which has activator proteins, mediator proteins, promoter, RNA polymerase, and transcription factors

elongation

Which has transcription bubble, template strand, coding region, coding strand, and RNA transcript

termination

Which has a terminator, codon, amino acid, post transcription processing

5’ cap and poly A tail, and pre mRNA splicing

What are the two steps of post-transcriptional processing?

3 nucleotides of mRNA transcript

What makes up a codon?

anitcodon

Each tRNA has what?

tRNA brings

What brings the amino acids that correspond with the nucleotides?

comb

What does tRNA look like?

opens DNA

What is DNA helicase

changes shape of dna

Topoisomerase

builds an RNA primer

DNA primase

adds complementary nucleotides to 3’ of RNA primer

DNA polymerase 3

replaces the RNA with DNA

DNA Polymerase 1

seals the gap of both replica strands

DNA ligase

open end

Replication Fork

open space of replication

Replication bubble

starting strands

RNA primer

cell growth

G1 is?

DNA synthesis, duplication, sisters are joined at centromeres, centrioles reproduce

S is?

Growth, cytoskeleton disassembles

G2 is?