• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/233

Click to flip

233 Cards in this Set

  • Front
  • Back
The theory of endosymbiosis refers to...
the notion that, over the course of evolution, mitochondria and chloroplasts arose from the prokaryotic cells
The 9+2 pattern of the axoneme is nine____of tubules and two additional microtubules in the center called the____?
outer doublets; central pair
The main function of ribosomes is in:
protein synthesis
Which chemical group is at the 5' end of a single polynucleotide strand?
Phosphate group
The RER gets its names because its membranes are studded with...
Ribosomes
The pyrimidine bases are.. ...
Cytosine, Uracil, Thymine
Most cell membranes are composed principally of.. ..
proteins and lipids
Biologically, which of the following is the least important characteristic of water?
good solvent, numerous H bonds, hydrogen isotopes, polarity, or temp-stabilizing capacity?
Water typically contains isotopes of Hydrogen bonds
What are some characteristics of DNA?
Complementary strands
Composed of nucleotides
Antiparallel configuration
Double stranded

(does not contain ribose)
Prokaryotes have __S ribosomes with __S and__S subunits, whereas eukaryotes have__S ribosomes with__S and__S subunits.
70, 50, 30...80, 60, 40
The mitochondrion is where___cellular process takes place?
Respiration
Which part of the mitochondrial membrane contains porins?
the outer mitochondrial membrane
Which part of the mitochondrial membrane contains cristae?
the inner mitochondrial membrane
What is cristae?
The site in the mitochondria for for electron transport and ATP Synthesis
What is the DNA/Protein complex that contains genetic material?
Chromatin
What are the two types of chromatin?
Euchromatin, the open configuration & Heterochromatin, the densely packed, transcriptionally-closed
Transcription can occur in both the mitochondria and nucleolus?
True, transcription can take place in both of these cellular organelles
Where in the Mitochondria does Krebs Cycle take place; where mitochondrial DNA resides; and contains semi-fluid of the mitochondria
The Mitochondrial Matrix
This mitochondrial membrane is responsible for nucleotide phosphorylation?
The Intermembrane Space
The Powerhouse of the Cell?
Mitochondria
**What is the executioner of the cell; for programmed "cell death" ?
Apoptosis
Describe the Endosymbiotic Theory
That both the mitochondria and chloroplast evolve from ancient bacteria
Translation can occur in the cytoplasm and also ribosomes?
True
What are the sizes of prokaryotic and eukaryotic ribosomes?
Prokaryotes are 70S with subunits of 50S and 30S, while the eukaryotes are 80S with subunits of 60S and 40S
The SER functions to synthesize?
Lipids
The RER functions to synthesize?
Proteins and also functions in protein modification
Anterograde Transport
Movement of material from the ER through the Golgi complex towards the plasma membrane...
Retrograde Transport
Movement of vessicles from the golgi cisternae back towards the ER
Is the Endomembrane system and microubules intimately connected?
Yes, they are...
How are proteins modified in the RER?
They are modified here by adding a carbohydrate chain
What AA are used for N-linked glycosylation?
Asparagine
What is the terpene carrier for carbohydrates?
Dolichol
What is the gene affected for patients with CF?
Delta F508 Gene
The mutates CFTR gene would still be functional under which conditions...?
That it could still make it to the cell surface, passing through the membrane...but this never occurs.
If a protein is not properly folded, what is used as a marker to destroy it?
Ubiquitin destroys them using proteosomes and their proteases
What enzyme, found in the mitochondria, involved in phosphorylation, is found in the liver cells and involved with detoxification of drugs and meds??
Cytochrome P450's
What is the principle organelle involved in detoxification and drug metabolism that also conjugates noxious substances?
Smooth ER
What is involved in glycosylation, phosphorylation, and processing/packaging that is located near the ER, centrosome, and nucleus
The Golgi Complex
What are the 5 layers of the Golgi Complex?
CGN, cis, medial, trans cisternae, TGN
Where does most of the packaging occur in the golgi?
TGN
How do we move cell products from one part of the endomembrane system to the other?
Vessicles
Each of the 5 parts of the Golgi Complex are functionally and biochemically distinct?
True
Using endosomes, how do we get proteins to lysosomes?
Tag with a mannose-6-P so they can be secreted directly via lysosomal pathways
What is I-cell Disease
The inability to tag a protein with mannose-6-P results in I-Cell Disease
What are the different types of endosomes?
Early, Late endosomes, and Lysosomes
What do Lysosomes contain?
A single-membrane bound organelle that contains Acid Hydrolases
Which enzyme produces hydrogen peroxide?
Urate Oxidase
Which enzyme destroys H2O2?
Catalase
What are the three components of the cytoskeleton?
Microtubules, Intermediate Filaments, Microfilaments
The component of the cytoskeleton is crucial to diagnose the location of tumors; is the most stable; and can vary in tissue types
Intermediate Filaments
A hollow tube with a wall consisting of 13 protofilmaents and alpha and beta-tubulin
Microtubules
Actin that is by itself is called...
G-Actin
Bound Actin is called...
F-Actin
The dense network of microfilaments beneath the plasma membrane is called...
the Cell Cortex
Key Features of microvillus?
Absorption due to actin microfilaments
An example of actin-myosin movement?
Skeletal Muscle Contraction
What are mictrotubules consisting of?
Alpha and beta tubulin
What is the Axoneme structure?
"9+2" pattern with 9 outer doublets of tubules and 2 additional MT in the center
What is the role of gamma-tubulin?
Nucleation
The motor protein in the axoneme is called...
Dynein
Anything that disturbs the structure of a hemidesmosome results in...
A Blistering Disorder
What are the IF attached to desmosomes and hemidesmosomes?
Tonofilaments
Gap Junctions are...
Cell Junctions for rapid communication
What Junction anchors cells to the basement membrane?
Hemidesmosomes
What is the fn of Tight Junctions?
Serve as Permeability Barrier and Cell Polarity
The most abundant lipids in the plasma membrane?
Phopholipids
Where do you find phosphatidylserine and why?
On the cytosolic side of the membrane because of its negative charge
Spingolipids contain...
Choline
Which membrane lipid is responsible for blood types?
Glycolipids
What is Tay-Sachs Disease?
The inability to break down the GM2 gangliosides
What characteristics of Fatty Acids induce greatest membrane fluidity?
Short C-chain, Unsaturated, Lower temperatures
What characteristic of fatty acids induces minimal membrane fluidity?
Longer C-Chain, Saturated, Higher temps
Where are glycolipids found?
On the surface of all plasma membranes
What is the precursor steroid hormone that allows permeability?
Cholesterol
Localized regions of membrane lipids that are involved in cell signaling; Microdomains?
Lipid Rafts
Describe the outer membrane Lipid Rafts
have elevated cholesterol and glycosphingolipds, so they tend towards lesser fluidity and thicker areas of the membrane
Cholesterol tends to be a...
thicker membrane
What is a glycocalyx?
The sugary coat outside the cell; carbohydrate-rich zone outside cell
What is Osmosis?
movement of water from low solute concentration to an area of high solute concentration
Describe Hypotonic
Solution of lower solute concentration than inside the cell; induces cell lysis
Describe Hypertonic
Solution of higher solute concentration than inside the cell; induced crenation
What are the two types of carrier proteins for transport?
Uniport, Cotransport
Carrier protein for single solute transport & example
Uniport; Glutpermeases as an example
What are two types of Cotransport?
Symport transports in the same direction, and Antiport tranports in the oppositde direction. Exa re Cl-Bicarb exchangers
What are the 3 types of ion channels?
Voltage-gated, Ligand-gated, Mechanosensitive
An example of indirect active transport is?
Na-Glucose Symporter where the cell creates the gradient
Describe direct AT and give example
Energy in the form of ATP is spent in the process, an example is Na/K pump
GTPases are inactive (turned off) when bound to?
GDP
GTPases are active (turned on) when bound to?
GTP
What is Ras?
A monomeric GTPase
What inactivates Ras?
GAP (GTPase Activating Proteins)
What activates Ras?
SOS is a GEF (Guanine Exchange Factor) that turns on Ras
What can activate the Ras pathway?
Tyrosine Kinase growth factor
What is SOS?
SOS is a Guanine-nucleotide exchange factor, associated with GRB2
What are the four types of transport ATPases?
P-type, F-type, V-type, ABC-type
What type of transport ATPases are responsible for maintaining an ion gradient across the membrane like the Na/K pump and proton pump in the stomach
P-type ATPases
What type of transport ATPases found in bacteria, chloroplasts, and in mitochondria ATP synthases?
F-type ATPases
What type of transport ATPases pump protons into organellse and structurally related to F-type ATPases?
V-type ATPases
Large superfamily, handles a wide variety of solutes (ions, sugars, AA, peptides, polysaccharides)?
ABC-type ATPases
What are examples of ABC-type transporters?
CFTR, chloroquine transporter, multidrug resistant proteins
What is the nucleolus Organizer Region?
a stretch of DNA carrying multiple copies of rRNA genes
What contains the nucleolus organizer region (NOR)?
The Nucleoli
rRNA genes reside on which acrocentric chromosomes?
13, 14, 15, 21, 22
What bond holds the nucleotides together?
Phosphodiester bonds
The double helix DNA strands are held together by?
Hydrogen Bonds
Nucleosomes are made of ?
Histones (H2A, H2B, H3, H4); also has 146 bp of DNA wrapped around histone octamer
DNA that is scattered across the genome?
Interspersed DNA
Where do you find repetitive DNA?
Centromeres and Telomeres
Multiple copies of DNA arranged next to each other in a row?
Tandemly repeated DNA
Abnormal recombination between different copied of the repeats can lead to...
Deletion or rearrangement of the gene
Sequences that have 300bp, have been implicated as the cause of mutations in hereditary diseases by retrotransposition?
Alu and L1
The histones that binds to linker DNA
H1
DNA wrapped in nucleosomes can form, slightly thicker fibers and require... ..?
30nm- chromatin fiber, requires H1
30nm chromatin is aka...?
Solenoid
Trancriptionally Active genes are located in...also are acylated histones... ..
Euchromatin

**acetlyation is associated with increased transcription
Highly-folded chromatin that is usually transciprtionally inactive, methylated DNA is often associated with it.. ..
Heterochromatin
What is epigenetic?
Any factor that can affect gene function without change in the genotype
What is a Barr Body?
The inactive X chromosome in female cells
Place on chromosome that contains the DNA sequence for a particular gene?
Gene Locus
What are the stages of the cell cycle?
G1, "G0", S, G2, M phases
Stage of cell cycle that no DNA synthesis occurs?
G1
If GF's are not available during G1, what happens to the cells?
Cells enter a quiescent stage, G0
What stage of the cell cycle does DNA synthesis occur, where DNA is doubled?
S phase
What holds the sister chromatids together?
Centromeres
What is a kinetochore?
Where MT attach in the M phase
What is the direction of DNA synthesis?
5' --> 3'
What is the direction to read the DNA template?
3' --> 5'
Unwinding the DNA helix requires?
Helicase, topoisomerases, and Single stranded binding proteins
What controls supercoiling?
Topoisomerases
What unwinds DNA
Helicase
What do SSBs do?
To maintain DNA in the open configuration
A type-II topoisomerase used by bacteria?
DNA Gyrase
What initiates DNA replication?
Primase, an RNA polymerase
Okazaki fragments are joined by?
DNA ligase
What are the stages or subdivisions in mitosis?
Porphase, prometaphase, metaphase, anaphase, telophase (PPMAT)
Stage of mitosis where the nuclear membrane breaks down
Prometaphase
What stage where sister chromatids separate and move towards opposite poles?
Anaphase
Formation of mitotic spindle
Prophase
Describe Cytokinesis
Division of the cytoplasm, formation of 2 cells from 1
What drives process of Cytokinesis?
Contractile ring
What is the function of Meiosis I?
Separation of the homologs
What is the function of Meiosis II?
Separation of sister chromatids
Stage of Meiosis I where genetic recombination occurs and synaptonemal complex forms
Prophase I
Chromosomes held together in metaphase I where homologs are still crossing over?
Chiasmata
What are the two major rest points in female cells?
Diplotene (in prophase I) and metaphase II
What are the subdivisions of prophase I in meiosis I?
leptotene, zygotene, pachytene, diplotene, diakinesis
How are cells held together in the zygotene?
Synaptonemal complex
What subdivision of meiosis I is the stage of max condensation?
Diakinesis
What is nondisjunction?
Failure of two members of a homologous chromosome pair to separate during anaphase
Of the following lipids, which is found in approximately equal amounts in both the outer and inner portions of the lipid bilayer?
A) phophatidyl ethanolamine
B) phosphatidyl choline
C) phosphatidyl serine
D) cholesterol
E) all of the above
Cholesterol
Charlie, an Angus bull, is heterozygous (Bb) for coat color, where B = black and b = brown. Charlie therefore has a black coat. Black is Charlie's
A) homozygous state.
B) gene conversion.
C) genotype.
D) phenotype.
E) heterozygous state.
Phenotype
In eukaryotes, enzyme responsible for transcribing most protein-coding genes is
A) RNA polymerase III
B) RNA polymerase II
C) RNA polymerase I
D) All three types of RNA polymerase can transcribe protein-coding genes
RNA Polymerase II
In eukaryotes, the "start" codon also specifies the amino acid,
A) phenylalanine
B) glycine
C) valine
D) aspartate
E) methionine
Methionine
Which amino acid residue is the site of N-linked glycosylation?
A) Asparagine
B) Arginine
C) Threonine
D) Serine
E) Both threonine and serine
Asparagine
The regions of DNA in a eukaryotic gene that encode a polypeptide product are called:
A) enhancers
B) ribosomes
C) leader sequences
D) promoters
E) exons
Exons
Which of the following is not part of a human chromosome in any phase?
A) histone
B) centriole
C) euchromatin
D) nucleosome
E) centromere
Centriole
The nuclear membrane functions as a

A) means of sequestering many of the mRNA processing activities from the cytosol.
B) selective barrier, allowing certain substances in or out.
C) means of separating nuclear and cytoplasmic constituents.
D) means of localization of the chromosomes within the cell.
E) all of the above
All of the above
The stage of meiosis where cells become haploid.
A) anaphase I
B) prophase I
C) prophase II
D) anaphase II
Anaphase I
The appropriate folding of a newly translated product is essential, and continual misfolding often leads to disease, especially in vertebrates. This misfolding, particularly in the situation of prion diseases, may be due to

A) chaperone activity.
B) errors facilitated by the enzyme foldase.
C) errors perpetuated during self-assembly.
D) insertion of inappropriate amino acids during translation.
E) rearrangements by translocase.
Chaperone Activity
Which of the folowing terms describes the role of the glucocorticoid receptor?
A) TATA box
B) Cis element
C) Promoter
D) Transcription factor
E) Enhancer
Transcription Factor
DNA replication is
A) conservative.
B) irregular.
C) semi-conservative.
D) spontaneous
E) dispersive.
Semi-Conservative
Which of the following are termination codons?
A) UUU, UAA & UAG
B) UUU, UAG, UGA & UAA
C) UGA, UAA & UAG
D) AUG & UAA
E) AUG, UAA, UGA & UAG
UGA, UAA, UAG
The site of RNA polymerase binding to the DNA template is called
A) Carboxyl end
B) Domain
C) Promoter
D) Enhancer
E) Leader sequences
Promoter
DNA replication
A) is not edited once polymerization has occurred.
B) is conservative.
C) is partially regulated by promoter/terminator sites.
D) proceeds by making two continuous strands.
E) requires a type of RNA polymerase
Requires a type of RNA Polymerase
The alternative forms of a gene that can be expressed are known as
A) loci
B) alleles
C) spores
D) haplotypes
E) genes
Alleles
Which of the following is the correct order of the levels of DNA packaging in eukaryotic chromosomes?
A) nucleosome → looped domains → chromatin fiber → heterochromatin
B) chromatin fiber → nucleosome → looped domains → heterochromatin
C) heterochromatin → nucleosome → chromatin fiber → looped domains
D) chromatin fiber → heterochromatin → nucleosome → looped domains
E) nucleosome → chromatin fiber → looped domains → heterochromatin
Nucleosome-->chromatin fiber-->looped domains-->heterochromatin
A patient has been diagnosed with having a cancerous tumor. It has been discovered that a malfunction is occurring in his cell signaling pathway. Which of the following mutations would likely contribute to tumor formations?
A) GTP staying bound to RAS
B) PIP 3 becoming dephosphorylated
C) AKT being degenerated
D) GDP staying bound to RAF
GTP staying bound to Ras
DNA polymerase uses a nucleoside triphosphate, bearing phosphates on the 5' carbon to form a phosphodiester linkage to the free 3' hydroxyl group on the end of the DNA strand it is synthesizing.
A) True
B) False
True
Which of the following is NOT a function of membranes?
A) regulation of transport
B) information storage
C) cell-cell communication
D) compartmentalization
E) delineation
Information Storage
The major lipids found in membranes are
A) cholesterol and sphingomyelin
B) phospholipids, glycolipids, and cholesterol
C) triacylglycerols and cholesterol
D) phospholipids and free fatty acids
E) cholesterol, inositol, and glycolipids
Phospholipids, glycolipids, cholesterol
Which of the following molecules would NOT readily cross an intact cell membrane by simple diffusion?
A) oxygen
B) glucose
C) fatty acids
D) water
E) ethanol
Glucose
An example of a purine is
A) uracil.
B) cytosine.
C) guanine.
D) acridine.
E) thymine.
Guanine
What protein will cause the activation of RAS?
A) SOS
B) GRB2
C) RAF
D) RAS Kinase
E) MAPKK
SOS
With regard to the semipermeable nature of the plasma membrane, which of the following would readily cross without the aid of a transport protein?
A) glucose
B) calcium ions
C) amino acids
D) water
E) DNA
water
The phases of meiosis that most resemble those of mitosis are
A) meiosis I, except for the pairing of homologs.
B) meiosis II, except for the pairing of homologs.
C) the meiosis I phases.
D) the meiosis II phases.
E) both A and B
Meiosis II Phase
With respect to the outer and inner faces of the lipid bilayer of the cell membrane, the composition of lipids is
A) asymmetrical.
B) not identical, but symmetrical.
C) highly random and varies throughout the cell.
D) a mirror image.
E) identical.
Asymmetrical
The phase of the cell cycle associated with the doubling of the amount of DNA in the cell is
A) M.
B) G1.
C) S.
D) G0.
E) G2.
S
Based on your knowledge of the chemistry of the cell membrane, which of the following compounds would you couple with a new drug in order to achieve better uptake by cells?
A) polar amino acids
B) lipids
C) several mannose-6-phosphate monomers
D) any hydrophilic substance
E) carbohydrates
Lipids
Where would you expect to find an organism possessing a cell membrane with the following composition: large proportions of cholesterol and a predominance of unsaturated fatty acids?
A) upper levels of an aquatic environment
B) frozen wastelands
C) tropical regions
D) temperate regions
E) equatorial regions
Frozen Wastelands
Of the subphases of prophase I of meiosis, the phase at which mammalian egg cells are arrested for years during oogenesis is
A)

diakinesis.
B)

diplotene.
C)

pachytene.
D)

leptotene.
E)

zygotene.
Diplotene
Transcription is similar to DNA replication in that
A)

an RNA transcript is synthesized discontinuously and the pieces then
joined together.
B)

nucleotide polymerization occurs only in the 5..-to-3.. direction.
C)

the newly synthesized RNA remains paired to the template DNA.
D)

it uses the same enzyme as that used to synthesize RNA primers during
DNA replication.
Nucleotide Polymerization occurs only in the 5'-->3' direction
Which lipids can be found in a plasma membrane?
A)

phospholipids.
B)

sphingolipids.
C)

cholesterol.
D)

both B and C
E)

choices A, B, and C
choices A, B, C
The proteins which complex with DNA producing the "beads on a string" or nucleosomes are called:
A)

histones

B)

proteases
C)

kinases

D)

spindle fibers
Histones
Which component of transcribed RNA in eukaryotes is present in the initial transcript but is removed before translation occurs:
A)

3' Poly A tail
B)

codons coding for the protein to be produced
C)

Ribosome binding site
D)

Intron
E)

5' cap
Intron
A sample of cells is placed in a salt solution. The cells shrink and the membrane is distorted. Relative to the cell, the solution is probably:
A)

isotonic

B)

hypotonic

C)

hypertonic

D)

osmotic
Hypertonic
Release factors of translation recognize the codon
A)

AUG.

B)

GGA.

C)

UGA.

D)

GUA.

E)

UUU.
UGA
Which of the following can be classified as a glycolipid?
A)

sphingomyelin
B)

cerebroside (galactocerebroside)
C)

phosphatidylcholine
D)

phosphatidylserine
E)

cholesterol
Cerebroside (galactocerebroside)
Which enzyme is responsible for amino acid acitivation and the joining an amino acid to a tRNA?
A)

IF2
B)

Peptidyl transferase
C)

N-formylmethionase
D)

Amino hydroxylase
E)

Aminoacyl-tRNA synthetase
Aminoacyl-tRNA synthetase
Which of the following regions of a gene tells RNA polymerase where to start
transcribing DNA into RNA?
A)

5' capping signal
B)

promoter
C)

coding region
D)

terminator
E)

enhancer
Promoter
How thick is a DNA solenoid?
A)

30 mm
B)

10 nm
C)

700 nm
D)

30 nm
E)

None of the above
30nm
What is another common name for lipid rafts?
A)

Microdomains
B)

Lipofuscins
C)

Glycosphingoids
D)

Clatherins
E)

Residual bodies
Microdomains
Transcription of 18S, 28S and 5.8S ribosomal RNAs is primarily the function of
A)

RNA polymerase I.
B)

RNA polymerase III.
C)

primase.
D)

mitochondrial RNA polymerase.
E)

RNA polymerase II.
RNA Polymerase I
Which of the following statements about RNA processing is true?
A)

Capping on the 3' end of the RNA is important for RNA stability
B)

RNA splicing removes exons from the RNA transcript
C)

The poly-A tail is added to the 3' end of RNA by a special polymerase called poly-A polymerase
D)

RNA splicing occurs in the cytoplasm once the transcript is bound to a ribosome
The poly-A tail is added to the 3' end of RNA by a special polymerase called poly-A-polymerase
Cholesterol
A)

destabilizes the cell membrane.
B)

intercalates between the fatty acid chain within the bilayer.
C)

increases permeability for small cations.
D)

is found in abundance in prokaryotic cell membranes.
E)

all of the above
intercalates btwn the FA chain within the bilayer
By convention, the sequence of bases in a nucleic acid is usually expressed in the _________ direction.
A)

3' to 5'
B)

5' to 3'
C)

1' to 3'
D)

clockwise
E)

3' to 1'
5'-->3' direction
Which structure includes all of the others?
A)

genes

B)

chromosomes
C)

nucleolus

D)

nucleus
Nucleus
The main function of ribosomes is in:
A)

DNA replication

B)

Protein synthesis
C)

Transcription

D)

Respiration
Protein Synthesis
Which chemical group is at the 5' end of a single polynucleotide strand?
A)

Diester group
B)

Purine base
C)

Phosphate group
D)

Nitrogen group
E)

Hydroxyl group
Phosphate Group
Most cell membranes are composed principally of
A)

DNA and ATP

B)

chitin and starch
C)

proteins and lipids

D)

nucleotides and amino acids
Proteins & Lipids
Which of the following is NOT a characteristic of DNA?
A)

complementary
B)

composed of nucleotides
C)

antiparallel
D)

double-stranded
E)

contains ribose
contains ribose
A protein is destined to be secreted from a cell. In which organelles would you expect to find the protein after it is produced in the rough endoplasmic reticulum?
A)

endosome
B)

secretory vesicle
C)

Golgi apparatus
D)

lysosome
E)

nucleus
golgi apparatus
The microtubule-organizing center (MTOC)
A)

acts as an anchor for both ends of the microtubule.
B)

is called a centrosome during interphase.
C)

is associated with two centrioles in plant cells.
D)

is positioned near the cell membrane.
E)

serves as a site for microtubule and microfilament assembly.
is called a centrosome during interphase
Intermediate filaments are
A)

composed of actin
B)

composed of globular proteins only.
C)

different in different cell types.
D)

smaller than actin filaments.
E)

composed of tubulin.
different in different cell types
In a nucleic acid, the bases are always attached to the _______________ carbon of the sugar.
A)

2'

B)

5'

C)

4'

D)

1'

E)

3'
1'
The smooth endoplasmic reticulum functions in synthesis of
A)

polysaccharides.
B)

lipids.
C)

proteins.
D)

DNA.
E)

all of the above
Lipids
The __________ is a complex network of interconnected filaments and tubules that extends throughout the cytosol, from nucleus to the inner surface of plasma membrane.
A)

desmin sheath
B)

cytoskeleton
C)

microfilament array
D)

microtubule apparatus
E)

cell scaffold
Cytoskeleton
In nucleic acids, the free hydroxyl group is attached to the _______________ carbon of the sugar.
A)

2'

B)

5'

C)

3'

D)

4'

E)

1'
3'
Why do polar substances such as sodium chloride (NaCl) dissolve so readily in water?
A)

The sodium ions repel the partial negative end of the water dipole.
B)

NaCl is a very dry powder, and the water is able to soak into the salt.
C)

The nonpolar ends of the water molecules are able to surround the charged salt ions.
D)

Spheres of hydration form between the water and the ions.
Spheres of Hydration form between the water and the ions
Which organelle has only a single membrane around it?
A)

mitochondrion
B)

ribosome
C)

nucleolus
D)

nucleus
E)

peroxisome
Peroxisome
F-actin filaments
A)

are oriented similar to DNA, with strands helical and antiparallel to one another.
B)

are composed of G-actin dimers.
C)

are composed of polymerized G-actin monomers wound around each other in a helix.
D)

are composed of four linear strands.
E)

polymerize at the same rate in both directions from both ends of the filament.
composed of polymerized G-actin monomers wound around each other in a helix
Pericentriolar material is composed of numerous rings of __________ in combination with a protein known as __________ within the centrosome.
A)

gamma tubulin; pericentrin
B)

alpha tubulin; cilium
C)

pericentrin; tubulin GTP
D)

beta tubulin; tubulin GTP
E)

alpha tubulin; gamma tubulin
Gamma-tubulin; pericentrin
Why is a selectively permeable membrane so important to living things?
A)

It allows cells to attach to adjacent tissues.
B)

Proteins will avoid a selectively permeable membrane.
C)

It provides a good barrier between the inside and outside of the cell.
D)

The membrane may absorb many times its weight in cholesterol.
E)

all of the above
Provides a good barrier between the inside and outside of a cell
Which statement best describes the function of the Golgi apparatus?
A)

Production of energy during photosynthesis
B)

Synthesis and assembly of membrane and secreted proteins
C)

Digestion of extracellular material
D)

Specific transport and signaling systems
E)

Processing of membrane and secreted proteins, including glycosylation
Processing of membrane and secreted proteins, including glycosylation
The methanobacteria, halobacteria, and sulfobacteria are included in which bacterial group?
A)

cyanobacteria
B)

archaebacteria
C)

blue-green algae
D)

eubacteria
E)

all of the above
Archaebacteria
Which of the following is a disaccharide?
A)

glucose
B)

lactose
C)

fructose
D)

N-Acetlyglucosamine
E)

galactose
Lactose
In relaxed muscle, calcium is found in high concentration in the
A)

myofibril.
B)

sarcolemma.
C)

sacroplasmic reticulum.
D)

T tubules.
E)

neuromuscular junction.
Sarcoplasmic Reticulum
The inside of the bilayer is
A)

hydrozine

B)

hydrophallic
C)

hydrophobic

D)

hydrophilic
Hydrophobic
Which type of bond links glucose units together in glycogen?
A)

β(5'->3')
B)

β(6->4)
C)

α(1->4)
D)

β(1->4)
E)

α(5'->3')
alpha (1-4)
Which of the following is an eukaryotic characteristic?
A)

cell fission

B)

membrane-bound nucleus
C)

little processing of RNA

D)

70S ribosomes
membrane-bound nucleus
Communication between animal cells is facilitated by
A)

plasmodesmata.
B)

gap junctions.
C)

adhesive junctions.
D)

tight junctions.
E)

both B and C.
Gap Junctions
What is at the 2' position of a RNA nucleotide?
A)

phosphate group
B)

methyl group
C)

a hydrogen molecule
D)

hydroxyl group
E)

a nitrogenous base
Hydroxyl group
In some diseases like cystic fibrosis, a cell membrane receptor fails to function. In the majority of cases, the problem comes from a change in the receptor so that it cannot reach the cell surface. The site in the cell where membrane proteins are synthesized and assembled builds up with the abnormal protein. This site would likely be the:
A)

peroxisome
B)

nucleus
C)

mitochondria
D)

lysosome
E)

endoplasmic reticulum
ER
Which of the following processes would be most likely to occur in the Golgi apparatus?
A)

glycosylation of proteins
B)

detoxification of drugs
C)

synthesis of steroids
D)

synthesis of DNA
E)

production and packaging of lipids
glycosylation of proteins
What does the BCL2 Protein do?
Controls Apoptosis in the mitochondria, like Cytochromes C does
What is the function of Colchicine?
degrades MT infrastructure
Taxol is used for...
a great breast cancer drug
Statins...
prevent cholesterol formation
Clathrin coat for Lysosomes functions as...
a protein coat spontaneously forming a cage around the vessicles...
What is the process that occurs at the 5 position of cytosine and often correlates with gene inactivation?
Methylation
What modification of histones is characteristic of actively transcribed chromatin and can weaken the binding of histones to DNA or alter their interactions with other proteins?
Acetylation
There is sometimes reverse transcriptase activity in Euakryotes even if the cells are not infected with a virus...this activity can be attributed to
the presence of retrotransposons
Where is the cellular location of the glucocorticoid receptor?
Cytosol
Most common proto-oncogenes mutated in cancer is Ras, which regulatory protein would be up-regulated if Ras was constitutively active in a tumor cell?
Raf