Download 33_organelles.txt 3/25/2010 Limited proteolysis, phosphorylation

33_organelles.txt
3/25/2010
Limited proteolysis, phosphorylation, and isoprenylation all occur here. In flagellate protozoa, it is known as the
parabasal body and in plants, it is known as the dictyosome. It was first described in 1898 but, because of the
limitations of light microscopy and because staining techniques failed to resolve its structure, its existence was not
proven until the late 1950s. FTP, name the organelle where glycosylation occurs and proteins are packaged for
secretion.
Answer: Golgi apparatus or Golgi bodies or Golgi sacs
Belgian biochemist Christian de Duve identified them in 1955 with the aid of an electron microscope. Originating as
buds on the trans-Golgi network, they have an acidic interior which can destroy other worn out organelles and cellular
invaders. For 10 points, name these organelles which take in extracellular molecules by fusing with endosomes.
Answer: lysosomes
The outer membrane is dotted with the protein porin, while ubiquinone and cytochrome oxidase complex line the
folded inner membrane. The double membrane is explained by the endosymbiont hypothesis which also helps explain
the presence of self-replicating DNA, similar to that found in bacteria. For ten points, name the cellular organelle
responsible for aerobic respiration.
Answer: mitochondrion or mitochondria
Composed of a stack of five to eight disk-shaped membraned vesicles, it is structurally polarized with a 'cis' face near
the transitional region of the RER and a 'trans' face near the plasma membrane. The principal director of cellular
protein traffic is, for ten points, what organelle named for its 1898 discoverer, an Italian cytologist.
Answer: Golgi apparatus or complex or body
They often stand out in electron micrographs because of a crystalloid core made up of urate oxidase. In germinating
seeds, they are called glyoxysomes, since they convert fats to sugars as part of the glyoxylate cycle. Remarkably
adaptable, they are small in yeast cells grown on sugar, but grow large if the yeast is transferred to methanol. For 10
points-name these organelles that break down many molecules by producing hydrogen peroxide.
Answer: peroxisomes
Swelling and the appearance of calcium deposits in this organelle signify that the cell is undergoing necrosis. Bounded
by a smooth outer membrane, its inner membrane consists of several shelf-like folds called cristae. Possessing its own
type of DNA, it contains the machinery for synthesizing proteins. FTP, what is this organelle which provides energy for
animal cells.
Answer: mitochondrion (or mitochondria)
Since these organelles differ in size and chemical properties between prokaryotes and eukaryotes, anitbiotics such as
tetracycline, streptomycin, and Zithromax can be used to target them and kill prokaryotic cells without hurting
eukaryotic cells. Each is composed of two subunits with characteristic shape, and contains a total of four RNA
molecules and about 70 different proteins. Manufactured in the nucleus and then released into the cytoplasm in order
to function, name these organelles that are directly involved in protein synthesis and which, FTP, are found floating in
the cytoplasm or attached to the endoplasmic reticulum.
Answer: ribosomes
In 2002, this compound was the first to be used successfully to prevent muscle loss in certain lung cancer patients. It
can be used to treat asthma and diabetes, and in the body it acts as a neurotransmitter, but its most important function
was discovered by Fritz Lipmann and Herman Kalkar in 1941. In cells, it readily loses a phosphate ion by hyrdolysis,
providing the means for organelles to carry out biological processes. The predominant source of energy in living cells,
FTP what is this compound named in part for the D-ribose component's possession of three phosphate groups.
Answer: ATP or adenosine triphosphate
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A drug known as brefeldin A blocks the transfer of proteins to this organelle, while vesicles bound for it tend to be
coated with either COP I or COP II. The current paradigm for its sorting abilities is explained by the "maturational
model", which states that proteins from the endoplasmic reticulum enter its cis face and are packaged in its cisternae,
after which they are transported out of the trans face. Composed of a stack of flattened sacks, FTP, identify this cellular
organelle, an apparatus named after an Italian anatomist.
Answer: Golgi complex or apparatus
Diseases caused by defects in these include hyperoxaluria, Refsum's disease, and Zellweger syndrome. Although
involved in bile acid synthesis, amino acid metabolism and cholesterol synthesis, the most important function of these
organelles may be the beta-oxidation of long chain fatty acids. FTP, name this type of organelle which contains enzymes
such as catalase and is named due to its role in the production and decomposition of hydrogen peroxide.
Answer: peroxisome(s)
It is surrounded by a single membrane called the tonoplast. Its storage variety is generally responsible for holding
phenolics, acids, nitrogenous wastes, and anthocyanins away from the cytosol. Its contractile variety is used to pump
water out of the cell quickly and plays a role in the cell's turgor pressure. Its food variety is responsible for
phagocytosis. Generally smaller in animal cells, plant cells usually contain one large version of this organelle. FTP,
identify this organelle that serves as a general repository for materials in cells.
Answer: vacuole
Discovered in 1950 by Rene de Duve, mannose-6-phosphate tags molecules destined for it. It secretes a hydrogen ion
ATPase in order to acidify its immediate environment. Born from endosomes in receptor-mediated endocytosis, Pompe
and Gaucher diseases are caused by its malfunction and a deficiency of hexosaminidase-A produced by this organelle
causes Tay-Sachs disease. Involved in apoptosis, its components are produced by the rough ER and packaged by the
Golgi body. FTP, name this organelle that digests macromolecules and releases lytic enzymes upon a cell's death.
Answer: lysosome
These organelles are particularly abundant in renal proximal convoluted tubule cells and liver parenchyma cells. Bound
by a single membrane, they contain type II oxidases like urate oxidase, whose action produces the compound for which
it is named. A predominant constituent is the enzyme catalase, which helps in the process of detoxification for which
this organelle is known. FTP, what is this organelle named for the presence of the compound H2O2?
Answer: peroxisomes
The dense fibrillar component of this organelle is thought to be the location of synthesis of rDNA, which later expands
to form this structure. Transcriptional silencing of this rDNA leads to the production of pre-ribosomal RNAs, which are
further modified by snRNAs to form mature ribosomal RNAs. These ribosomal RNAs are exported by the Cajal bodies to
the cytoplasm to form mature ribosomes. FTP, name this site of synthesis for ribosomes, located inside the nucleus.
Answer: nucleolus
Cytotoxic T cells secrete of perforin from these structures and melanocytes secrete melanin from a modified form of
them. In addition, their exocytosis provides the additional membrane needed to quickly seal wounds in the plasma
membrane. I-cell disease is caused by a failure to phosphorylate all enzymes that are supposed to be transported to
them. FTP, name these organelles that contain lipases, nucleases, proteases, and other digestive enzymes that break
down complex molecules in the body.
Answer: lysosomes
Lowe syndrome causes a deficiency of an enzyme which affects the metabolic processes that take place in this cell
structure. One of its main functions is the remodeling of oligosaccharides, while other functions include the synthesis of
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lipids like sphingomyelin and the addition of sulfate groups to tyrosine. Often located near endoplasmic reticulum exit
sites, it uses clathrin-coated vesicles to send certain proteins to lysosomes and other vesicles to secrete proteins from
the cell. FTP, name this organelle divided into stacks of flattened, membrane-bounded cisternae, which packages and
sorts newly-created proteins.
Answer: Golgi Apparatus/Body/Whatever
Since their DNA copying does not have any error checking, the probability of random mutation is much higher, leading
to diseases such as Kearn-Sayre syndrome. Its DNA typically consists of five to ten copies, all inherited from the mother,
and when they divide these copies are randomly distributed between the offspring. Some theories hold that its DNA is
derived from a single source called "Eve". FTP, what are these organelles long ago incorporated into eukaryotic cells to
produce energy for them?
Answer: mitochondria
In one of the forms of this, 6-Formylpterin enhances it by activating protein kinase C-prime, while it may be blocked by
upregulation of HSP-70. It is initiated by the migration by Bak or Bax to Bcl-2 binding sites, or via binding to CD95 by Fas
ligand. Exposure of peroxidized phosphatidylserine occurs in its final stages, after caspase 9 binds to cytochrome c from
the mitochondrion and a certain protease activates factor-1, leading to degradation of chromosomal DNA and
breakdown of cellular organelles into vesicles. FTP, name this process, which occurs in endometrial shedding during
menstruation and finger formation, and is a form of programmed cell death.
Answer: apoptosis [a-po-TO-sis] (prompt on programmed cell death)
Proteins destined for these structures are post-translationally modified to include mannose-6-phosphate residues on
their N-linked oligosaccharides. The addition of the M6P tag to enzymes, such as aryl-sulfytase A, is being investigated
as a potential treatment for diseases that affect these organelles, which diseases include metachromatic
leukodystrophy and Fabry's disease. Once inside these structures, the proteins and their M6P tags dissociate due to the
environment created by vacuolar ATPase, which is closely related to the proton pump used in oxidative
phosphorylation. FTP, identify these organelles containing hydrolases that function best at a pH of about 5 and which
are structurally similar to peroxisomes.
Answer: lysosomes
Defects in these objects can cause Kearn-Sayre Syndrome or Luft Disease. They contain porins to allow for passive
diffusion of selected molecules through their outer membranes. They provide evidence for Margulis' endosymbiotic
theory and are important to evolutionary and genetic studies due to their derivation solely from the mother. They allow
some ribosomes in their matrix to allow for processes such as chemiosmosis and the citric acid cycle. FTP, name these
organelles whose primary function is to convert organic materials into ATP, the so-called "powerhouses" of the cell.
Answer: mitochondria
The first atomic structure of one of these was published by Ban et al. in 2000. Its leading end is labeled P and is followed
by A. In prokaryotes, it is made of three strands and consists of 30S and 50S subunits; in eukaryotes it has four strands.
It uses an initiator called fMET and then works by using peptidyl transferase to bind two amino acids, creating a peptide
bond; it does this by reading mRNA and using tRNA to create its product. FTP, these, sometimes located within the
mitochondria or in the cytoplasm, are, what protein-assembling organelles, most commonly located on the rough
endoplasmic reticulum?
Answer: ribosomes (accept 50S ribosomal subunits or large ribosomal subunits until "strands")
Kearns-Sayre syndrome is caused by faults in this, and its normal direction of heritance, which is caused by
ubiquitination of it, can be reversed in certain species of Musa. Analysis of this commonly consists of sequencing of HVR
regions and was used to establish woolly mammoth descent as described in a December, 2005 Nature article. Its
existence strongly supports the endosymbiotic hypothesis with respect to its namesake organelle. In humans, it
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contains 37 known genes, most coding for tRNA's. FTP, name this genetic material generally inherited only for the
mother; a ribonucleic acid present in the "power plant" of cells.
Answer: mitochondrial deoxyribonucleic acid (prompt on deoxyribonucleic acid, mitochondria or mitochondrion)
A prolonged fast can activate a selective pathway in these structures that involves KFERQ proteins. I-cell disease results
from a defect in the addition of the mannose-6-phosphate moiety used to target enzymes to them, and a deficiency of
the enzyme glucocerebrosidase ("gloo-coh-ser-eh-BRO-sih-dase") in these organelles leads to Gaucher's ("go-SHAYZ")
disease. Their membranes contain hydrogen ion pumps and chloride ion channel proteins that maintain an interior pH
of about 4.8, ideal for their proteasomes and other hydrolytic enzymes. Autophagy occurs in, FTP, these organelles
responsible for enzymatic digestion of cell components and ingested matter.
Answer: lysosomes
Defective versions of these can result in RCPD, AMN, and X-linked adrenoleukodystrophy. Another defect results in the
inability to metabolize phytanic acid, a condition known as Refsum disease, and it is also the location where
plasmalogen synthesis begins. Some proteins being targeted to this organelle rely on a string of serine-lysine-leucine
residues at the C-terminus, the SLK sequence. Those amino acids bind to PTSR receptors, defects in which can cause
Zellweger syndrome. Fatty acids are oxidized to acetyl CoA here, though it is best known for the enzyme catalase. For
10 points, name this organelle that isolates and degrades toxic peroxide species.
Answer: peroxisomes
Noncanonical functions for this structure are regulation of telomerase, modification of microRNAs, interaction with viral
proteins, and sequestration of proteins important for tumor suppression and the cell cycle. Consisting of fibrillar
centers, dense fibrillar components, and granular components, it is surrounded by a layer of condensed chromatin.
Disappearing totally during mitosis, this structure is the location of 75% of the polymerase activity in the cell, primarily
through the transcription of rDNA through RNA polymerase I. Also the location of synthesis of tRNAs and signal
recognition particles, FTP, name this cellular organelle that is the primary site of ribosome synthesis, a subcomponent of
the nucleus.
Answer: nucleolus
Defects in mannose phosphorylation lead to their failure and I-cell disease, characterized by inclusion bodies similar to
those seen in Tay-Sachs disease. In excess, Vitamin A can induce hepatotoxicity by weakening the membrane of these
organelles in the liver. This break in their membrane releases hydrolytic enzymes, which cause the death of the cell.
FTP, name these organelles active during apoptosis, which act as the digestive system of the cell.
Answer: Lysosomes
One subclass of this organelle features the microsomal P450 oxidase system, which plays a key role in the first-pass
effect through the liver. Another variation of this organelle contains the protein calsequestrin, important in regulating
skeletal muscle contraction. In neurons this organelle produces many neurotransmitters, stains purple when exposed to
aniline, and thus is referred to as Nissl substance. Its most famous functions, however, are either lipid synthesis or
protein production. FTP, name this organelle continuous with the nuclear membrane that comes in sarcoplasmic,
smooth, and rough varieties.
Answer: endoplasmic reticulum [accept smooth endoplasmic reticulum before "calsequestrin"]
Techniques used to study this process involve detecting the breakdown of the LC3 protein, localization of LC3 to
eponymous bodies, and direct identification of these bodies by their characteristic double-membrane form.
Potentiators of this process include rapamycin, which induces formation of complexes of Atg proteins critical for
induction of it. Too much of it can cause type II programmed cell death, although in cancers it can also promote cellular
survival. Primarily induced in response to low nutrient levels, FTP, name this cellular process in which old organelles are
surrounded by a membrane and fused to lysosomes for recycling, which takes its name from the Latin for "self-eating."
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Answer: autophagy (accept type II programmed cell death before it is mentioned)
Proteins destined for this structure are tagged at their N-linked oligosaccharides by mannose-6-phosphate, which allow
receptors to mediate vesicular transport of tagged proteins. Malfunction of this process is the cause of inclusion cell
disease, while the lack of a critical enzyme inside this organelle leads to diseases such as Pompe's disease and Hurler
syndrome. The lack of hexos-aminidase A causing buildup of gangliosides in this organelle is the cause of Tay-Sachs
disease. Proton pumps and ion channels in this organelle maintain the pH of 4.8 that is critical for enzymatic function.
Discovered in 1949 by Christian de Duve, FTP, name these organelles that destroy cellular waste and aid in the
breakdown of macromolecules.
Answer: lysosomes
While its exact method of attachment and entry are unknown, it is thought to bind to the host cell via MSP-1. These
organisms are known for giving rise to a series of apical organelles throughout their life cycles, including the microneme,
the rhoptry, and the dense granule. A member of phylum Apicomplexa, it modifies the erythrocyte by exporting
proteins such as PfEMP1 on the host surface. Containing 14 chromosomes, 1 mitochondrion, and 1 plasmid, species in
this genus include falciparum, vivax, and ovale, and it changes form from a merozoite to a trophozoite, and then to a
sporozoite. FTP, identify this genus carried by the Anopheles mosquito, the agent that causes malaria.
Answer: Plasmodium
Leber optic neuropathy was the first disease to be associated with this organelle, while Kearns Sayre syndrome is
caused by defects in these which leads to Ophthalmoparesis and ptosis. The Tom and Tim proteins are involved with
translocation of proteins across their membranes. Cytochrome C is also found within these structures, and is released
into the cell to trigger apoptosis. These organelles have two membrane systems with the inner one possessing folds
called cristae, and they possess their own genome which is used to analyze matrilineal ancestry. For 10 points, name
this organelle, often referred to as the "power source" of the cell.
Answer: mitochondrion [or mitochondria]
One type of bodies found in these were identified by the fusion of RAR alpha with PML proteins in promyelocytic
leukemia patients. Pores in its membrane are made of proteins rich in phenylalanine and glycine residues, and import
into and export out of this structure requires karyopherins, and is regulated by Ran proteins. Cajal bodies are also found
in this organelle, which can be visualized by Hoechst or DAPI staining. The rough endoplasmic reticulum is continuous
with its double membrane, and it is the location of mRNA splicing as well as DNA transcription. For 10 points, name this
organelle which contains chromatin that is only found in eukaryotes.
Answer: nucleus
The flgB ["f-l-g-b"] operon controls transcription of the distal rod protein of its blepharoplast, and fliF proteins aggregate
into the MS ring of this structure. The secretion system referred to as T3SS uses a simpler version of one component of
this organelle. Nexin links the components of these organelles together, preventing them from being dissolved, while its
shaft passes through four rings, rather than two, in Gram-negative bacteria. In eukaryotes their motion results from the
alternating movements of two sets of dynein arms, while those of prokaryotes are screw-shaped and rotate. The
defining external feature of sperm cells, these are, for 10 points, what long structures in eukaryotes that whip back and
forward to allow for movement?
Answer: flagellum [or flagella]
HSP90 aids in the delivery of substances to the translocase of outer membrane complex found on these entities, which
are also the site of the combination of protoporphyrin IX with iron to form heme. Kearns-Sayre syndrome and Leber's
hereditary optic neuropathy are examples of diseases associated with the transfer of their genetic material, a process
which in over 99 percent of mammals involves maternal inheritance as there are roughly 1000 times more of these in
oocytes than in sperm. Along with chloroplasts, these are the subjects of endosymbiotic theory, and the foldings of its
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inner membrane are known as cristae. FTP, identify this double-membrane cell organelle that generates the majority of
the ATP in a cell.
Answer: mitochondria
One disorder involving this organelle is caused by a mutation in E325K on the NAGA gene, called Schindler disease. One
method of transporting molecules to it involves an hsc70-containing chaperone complex. Another disorder results in
enzyme transport to the extracellular space rather than this organelle and is called I-cell disease. Proteins are marked
for this structure with mannose-6-phosphate, and proton pump activity in this organelle maintains the acidic pH
necessary for its primary function. One genetic defect results in ganglioside buildup in this organelle and thus causes
Tay-Sachs disease. For 10 points, identify this cellular organelle that breaks down macromolecules with the aid of acid
hydrolases.
Answer: lysosome
Proteins destined for these structures often possess a C-terminal SKL sequence. Mutations in the ABCD1 gene lead to
a demyelination disease involving these organelles called adrenoleukodystrophy. In humans, a reduction in their
number is the cause of Zellweger syndrome. Beta oxidation of fatty acids to acetyl CoA occurs in these structures, which
also contain the enzyme catalase, which is responsible for breaking down a certain toxic material into oxygen and
water. For 10 points, name these organelles that isolate and destroy hydrogen peroxide.
Answer: Â peroxisome
Chloramphenicol stalls the activity of this structure, while reversal of its primary function is enabled by LepA. That
function is carried out using the GTPase activity of EF-G. One of its main substrates is assembled using the enzyme aaRS,
and in prokaryotes, its 16S portion attaches to the Shine-Dalgarno sequence. Designated 70S or 80S, this organelle
transfers a nascent peptide from its P-site to its A-site where aminoacyl-tRNA accepts the polymerizing protein chain.
The tRNAs then exit from its E-site. Coming in free and bound varieties, for 10 points, name this organelle sometimes
found on rough ER that contains two subunits and is the site of protein synthesis.
Answer: ribosome
In Drosophila, the fuzzy onions gene regulates the fusion of these organelles in sperm, which creates the nebenkern.
One disease that affects these organelles results in a “salt-and-pepper” pigmentation of the retina. In another
disease, these organelles take the appearance of “ragged red fibers” under a Gomori trichrome stain. In addition
to the aforementioned Kearns-Sayre syndrome, the TIM/TOM complex sees the translocation of proteins into them.
Enzymatic abnormalities in these organelles can result in significant oxidative stress, and cytochrome C is found within
these structures. It contains inner compartments called cristae. For 10 points, name these organelles with namesake
matrilineal DNA, known as the “powerhouse” of the cell.
Answer:  mitochondria [or mitochondrion]
Sodium-mediated antiport membrane proteins in these structures can be passively inhibited through the use of digitalis
extracts which block sodium-potassium ATPases. They are mechanically coupled to plasma membrane dihydropyridine
receptors. Though not found in neurons, they possess ryanodine receptors which can be activated when phospholipase
C cleaves PIP2 into DAG and the signaling molecule inositol trisphosphate. Depending on the cell type, extensions of
these structures form dyads or triads with adjacent T-tubules and they contain the protein calsequestrin. For 10 points,
name these structures found within muscle cells which store intercellular calcium and are a modified form of an
organelle that is continuous with the nuclear envelope and comes in a rough form.
Answer: sarcoplasmic reticulum [or SR; prompt on endoplasmic reticulum or ER]Â When TFEB translocates to the nucleus, it results in a corresponding increase in the number of these organelles. A
glycosphingolipid in this organelle, iGb3, is necessary for the production of natural killer cells. P-type lectins direct
enzymes that have been tagged with mannose-6-phosphate to this organelle. Christian Rene de Duve discovered this
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organelle after centrifuging liver cells and discovering an abnormally high amount of acid phosphatase. Malfunction of
this organelle can lead to a buildup of gangliosides in Tay-Sachs disease. For 10 points, name these organelles that
perform autophagy by digesting unneeded or excess cellular materials.
Answer: lysosomes
Proteins targeted for either this structure or the plasma membrane are tagged with the amino acid sequence Y-X-X-phi,
where X is any residue and phi is any hydrophobic residue. One protein found here, GAAP, was found in 2009 to reduce
the frequency of oscillations of cytosolic calcium concentrations. In plants, hemicelluloses and pectins are created here,
and it is location of sphingomyelin synthesis from ceramide. Sulfotransferases sulfate glycosaminoglycans and
proteglycans in this structure. Vesicles marked with the COPII ("cop-2") protein transport molecules from endoplasmic
reticulum to its cis face. This organelle is composed of flattened discs called cisternae. For 10 points, name this proteinmodifying organelle named for an Italian biologist.
Answer: Golgi body [or Golgi apparatus; or Golgi complex]
5. Cycads are some of the only plants to have them, and they are unique to eukaryotes. Like a longer structure, they
have a 9+2 arrangement of constituent structures which make up the axoneme. The Fallopian tubes use them to
conduct eggs from ovary to uterus and the trachea has a lining of them for cleaning purposes. Rotifers have a crown of
them, which in some species makes them spin like wheels, and several of them are also found on paramecium. For 10
points, identify these short organelles which allow many eukaryotic cells to move.
Answer: cilia [or cilium] (HSAPQ1)
4. Their dysfunction may cause Hurler syndrome, which arises from an iduronidase deficiency in these organelles. A
severe form of mucolipidosis, also called i-cell disease, occurs due to improper phosphorylation of a mannose sugar tag
applied to objects destined for them. Better known for failures that cause Tay-Sachs disease, they contain several acid
hydrolases which work within their acidic environments. For 10 points, identify these organelles, named for their
function of breaking down macromolecules acquired from phagocytosis.
Answer: lysosomes (HSAPQ1)
9. Structures found within it include ones discovered by Cajal, which are thought to be involved in the modification of
snRNPs. Alpha-solenoid and beta-propeller folds can be found in the pores located on the double membrane envelope
of this structure, which is continuous with the rough endoplasmic reticulum. Red blood cells lack this structure, which
contains protein-DNA complexes called euchromatin and heterochromatin. For 10 points, identify this organelle, which
houses the cell's genetic information.
Answer: nucleus (HSAPQ1)
This entity requires proper functioning of the protein frataxin, which, when mutated, causes Friedrich’s ataxia. Another
disease of these bodies limits eye movement and is known as Kearns-Sayre syndrome. Lynn Margulis popularized the
idea that these bodies are proteobacteria that underwent endosymbiosis. This organelle’s inner folds are called cristae,
and it contains its own DNA that is inherited exclusively from an organism’s mother. For 10 points, name this
powerhouse of eukaryotic cells.
Answer: mitochondria [or mitochondrion] (HSAPQ2)
Proteins required for transport of molecules into this structure include the Tic and Toc complexes, and adding two
arginine residues to the N terminus of proteins marks them for one part of this structure. Along with an analogous
structure found in all eukaryotes, this organelle is evidence for the (*) endosymbiotic theory. It consists of stacks of
thylakoids called grana; outside the thylakoids is a space called the stroma in which the Calvin cycle occurs. For 10
points, name this organelle responsible for carbon fixation through photosynthesis.
Answer: chloroplasts (HSAPQ3)
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This organelle is the site of p53 localization due to proteasome inhibition. Spliceosomal RNA is regulated by the small
RNA found here. During mitosis, the components of this structure are synthesized from chromosomal organizer regions,
and this structure coalesces from ten smaller structures after cell division. It contains (*) fibrillar centers and the
protein fibrillarin, which is involved in ribosomal RNA processing. For 10 points, name this organelle in which
components of ribosomes are assembled, found within the nucleus.
Answer: nucleolus (HSAPQ3)
A disease caused by a defect in these is characterized by progressive limitation of eye movement and is known as
Kearns-Sayre syndrome. This organelle contains cytochrome c, and, like the nucleus, this organelle has a double
membrane, with the (*) inner one featuring folds known as cristae. Like the nucleus and chloroplast, they also contain
their own DNA. The site of the Krebs cycle and completion of the electron transport chain, for 10 points, name this
organelle, the cell’s power source.
Answer: mitochondria [accept mitochondrion] (HSAPQ3)
In some organisms, DNA associated with this structure can confer atrazine resistance via the psbA gene. Organisms also
express a family of envelope protein translocases for this organelle called Tic and Toc. That aforementioned type of
DNA often forms trimers and tetramers. Molecules associated with this structure include plastoquinone and NADPH,
which is used in this structure’s electron transport chain. Stacks of thylakoids are found dispersed throughout the
stroma of this organelle. For 10 points, name this organelle, the main site of photosynthesis.
Answer: chloroplast (HSAPQ4)
One structure in this organelle forms in the presence of VIPP1 and contains the cytochrome b6f complex; that structure
contains plastocyanin. The presence of a peptidoglycan cell wall in this organelle in certain glaucophyte algae supports
the hypothesis that this organelle arose from endosymbiosis with cyanobacteria. This organelle's lamellae connect the
grana, stacks of structures called thylakoids, which sit inside its inner membrane. For 10 points, identify this common
organelle, whose stroma contains enzymes like rubisco, the site of photosynthesis.
Answer: chloroplast (09HFT)
This organelle can malfunction in a disease sometimes called acid maltase deficiency in which it fails to break down
glycogen. Another disease associated with this organelle may be treated by letting sialidase metabolize GM2
gangliosides. Proteins destined for this organelle are tagged with mannose-6-phosphate. A disease caused by a
hexosaminidase A deficiency in this organelle results in a retinal red spot and death by the age of four, Tay-Sachs. It
uses membrane proton pumps to keep its internal pH at ** For 10 points, name these digestive organelles.
Answer: lysosome (09HFT)
This organelle is responsible for the production of chondroitin sulfate, a group that binds to serine residues, as it is the
site of glycosaminoglycan synthesis. Retrograde transport from this organelle requires COPI [cop-one] proteins, and the
spiral-shaped protein dynamin pinches vesicles off of it. Called dictyosomes in plants, they consist of stacks called
cisternae. With a cis face opposite the endoplasmic reticulum and a trans face open to the cytoplasm, for 10 points,
name this site of macromolecule processing, an organelle named for an Italian scientist.
Answer: Golgi apparatus [or Golgi body; or Golgi complex; prompt on dictyosomes] (09HFT)
The abnormal creation of these objects in animal cells due to ineffectiveness of an enzyme in a related structure is a
major cytological symptom of mannosidosis. A series of HRP membrane flow studies have placed good bounds on the
rate at which these organelles can be created. HLA class II specialization occurs in these organelles after HLA class II is
injected into one (*) containing a degraded antigen. Cytoplasmic tail anchors can be used to target substances to these
organelles by vesicular transport to create plant bioreactors. In plants these cells are bounded by a membrane known
as a tonoplast, while in animal cells they are usually created by pinocytosis or phagocytosis. Used in plants to generally
store metabolytes and to maintain turgor pressure, FTP, name these organelles which consist of large, water-filled sacs
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used to store cellular materials.
Answer: vaculoes (TXTerrapin)
Posttranscriptional insertions and deletions of uridine residues occur in these structures in trypanosomes. These
structures are adversely affected in Barth syndrome due to a defect in the biosynthesis of cardiolipin. Other diseases
associated with them include Friedreich’s ataxia and Kearns-Sayre syndrome. Damage to them results in the formation
of a permeability transition pore and can trigger (*) apoptosis through the release of cytochrome c. They may contain
thermogenin when found in brown fat, and they contain the malate shuttle, which regenerates NADH inside them. FTP
name these organelles that contain F0F1 ATP synthase and that are the sites of the citric acid cycle and the electron
transport chain, generating energy for the cell.
Answer: mitochondria or mitochondrion (09Terrapin)
Weisberger et al noted that chloramphenicol inhibits the action of this structure in microbial cells, though not
mammalian ones, and the antibiotics edeine and pantamycin work by binding to this structure. Its L11 stalk allows for
the interaction with RF-1 that allows release from its substrates, and the structure it forms with its substrates is
stabilized by the interaction of its 16S arm with the (*) Shine-Dalgarno sequence in prokaryotes. This entity’s L1 stalk
binds to its deacylated substrate in the P-site, encouraging the ratcheting that brings about translocation of tRNA to the
E-site, and this organelle’s production occurs in the nucleolus. FTP, name this cellular organelle, which has two subunits
and is responsible for translation of mRNA into proteins.
Answer: ribosomes (09Terrapin)
The flgB ["f-l-g-b"] operon controls transcription of the distal rod protein of its blepharoplast, and fliF proteins aggregate
into the MS ring of this structure. The secretion system referred to as T3SS uses a simpler version of one component of
this organelle. Nexin links the components of these organelles together, preventing them from being dissolved, while its
shaft passes through four rings, rather than two, in Gram-negative bacteria. In eukaryotes their motion results from the
alternating movements of two sets of dynein arms, while those of prokaryotes are screw-shaped and rotate. The
defining external feature of sperm cells, these are, for 10 points, what long structures in eukaryotes that whip back and
forward to allow for movement?
Answer: flagellum [or flagella] (09Winter)
HSP90 aids in the delivery of substances to the translocase of outer membrane complex found on these entities, which
are also the site of the combination of protoporphyrin IX with iron to form heme. Kearns-Sayre syndrome and Leber’s
hereditary optic neuropathy are examples of diseases associated with the transfer of their genetic material, a process
which in over 99 percent of mammals involves maternal inheritance as there are roughly 1000 times more of these in
oocytes than in sperm. Along with chloroplasts, these are the subjects of endosymbiotic theory, and the foldings of its
inner membrane are known as cristae. FTP, identify this double-membrane cell organelle that generates the majority of
the ATP in a cell.
Answer: mitochondria (09Winter)
One type of bodies found in these were identified by the fusion of RAR alpha with PML proteins in promyelocytic
leukemia patients. Pores in its membrane are made of proteins rich in phenylalanine and glycine residues, and import
into and export out of this structure requires karyopherins, and is regulated by Ran proteins. Cajal bodies are also found
in this organelle, which can be visualized by Hoechst or DAPI staining. The rough endoplasmic reticulum is continuous
with its double membrane, and it is the location of mRNA splicing as well as DNA transcription. For 10 points, name this
organelle which contains chromatin that is only found in eukaryotes.
Answer: nucleus (08Fall)
Leber optic neuropathy was the first disease to be associated with this organelle, while Kearns Sayre syndrome is
caused by defects in these which leads to Ophthalmoparesis and ptosis. The Tom and Tim proteins are involved with
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translocation of proteins across their membranes. Cytochrome C is also found within these structures, and is released
into the cell to trigger apoptosis. These organelles have two membrane systems with the inner one possessing folds
called cristae, and they possess their own genome which is used to analyze matrilineal ancestry. For 10 points, name
this organelle, often referred to as the “power source” of the cell.
Answer: mitochondrion [or mitochondria] (08Fall)
Its residual body can form a lipofuscin pigment granule, and proteins like AP1 and GAAT are necessary for its function. An enlargement of it that causes damage to muscle cells is called Pompe (pom-PAY) disease, while a defect in sugar
metabolism causes it to malfunction in Hurler's syndrome. The home to V-class pumps, it takes in triskelion shaped
clathrin-bound vesicles, and proteins tagged by mannose-6-phosphate are bound for it. Critical for autolysis, FTP name
this organelle that uses proton pumps to generate an acidic environment where its hydrolases can act to digest
material.
Answer: lysosome (08Terrapin)
Proteins destined for these structures often possess a C-terminal SKL sequence. Mutations in the ABCD1 gene lead to a
demyelination disease involving these organelles called adrenoleukodystrophy. In humans, a reduction in their number
is the cause of Zellweger syndrome. Beta oxidation of fatty acids to acetyl CoA occurs in these structures, which also
contain the enzyme catalase, which is responsible for breaking down a certain toxic material into oxygen and water. For
10 points, name these organelles that isolate and destroy hydrogen peroxide.
Answer: peroxisome (09Fall)
Chloramphenicol stalls the activity of this structure, while reversal of its primary function is enabled by LepA. That
function is carried out using the GTPase activity of EF-G. One of its main substrates is assembled using the enzyme aaRS,
and in prokaryotes, its 16S portion attaches to the Shine-Dalgarno sequence. Designated 70S or 80S, this organelle
transfers a nascent peptide from its P-site to its A-site where aminoacyl-tRNA accepts the polymerizing protein chain.
The tRNAs then exit from its E-site. Coming in free and bound varieties, for 10 points, name this organelle sometimes
found on rough ER that contains two subunits and is the site of protein synthesis.
Answer: ribosome (09Fall)
One disease of this type sees the formation of curved structures called "banana bodies," while one example of this type
of diseases is treated by the drug miglustat. Another disease of this type sees the generalized occurrence of lesions
called angiokeratomas and is alternatively called angiokeratoma corporis diffusum. In addition to Farber’s disease and
Fabry's disease, these diseases are commonly associated with patients exhibiting hepatomegaly or splenomegaly. The
most prominent examples of these diseases include ones in which the activities of L-iduronidases are impaired,
exemplified by the Hurler syndrome and the Scheie syndrome. Other examples of these diseases include Gaucher's
disease, which sees improper functioning of beta-glucosidase. For 10 points, identify this class of diseases, wherein
macromolecules get accumulated in a certain organelle, whose other examples include the Tay-Sachs disease.
Answer: lysosomal storage diseases [accept equivalents; prompt on "diseases involving mutations of hydrolases"]
(09MO)
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