UCLNLP/adversarial_qa huggingface dataset:
Chloroplast

If angiosperm shoots are not exposed to the required light for chloroplast formation, proplastids may develop into an etioplast stage before becoming chloroplasts. An etioplast is a plastid that lacks chlorophyll, and has inner membrane invaginations that form a lattice of tubes in their stroma, called a prolamellar body. While etioplasts lack chlorophyll, they have a yellow chlorophyll precursor stocked. Within a few minutes of light exposure, the prolamellar body begins to reorganize into stacks of thylakoids, and chlorophyll starts to be produced. This process, where the etioplast becomes a chloroplast, takes several hours. Gymnosperms do not require light to form chloroplasts.

Question: How long does it take a prolameller to start forming chylakoids after exposure to chlorophyll?
Answer: a few minutes

Question: What stage comes before plastid?
Answer: proplastids

Question: What do angiosperms need that gymnosperms don't in order for chloroplast formation?
Answer: light

Question: What might happen if new angiosperm growths do not receive illumination?
Answer: an etioplast stage

Question: If angiosperm shoots don't get the required light what will they be lacking?
Answer: chlorophyll

Question: When given light what happens to the lattice of tubes in the stroma?
Answer: reorganize into stacks of thylakoids

Question: What is needed to turn an etioplast into a chloroplast?
Answer: chlorophyll

Question: What happens to the inner membrane invaginations when the etioplast is exposed to a light source?
Answer: begins to reorganize into stacks of thylakoids

Question: What forms tubes in the etioplast stroma?
Answer: inner membrane

Question: How are thylakoids organized for chlorophyll?
Answer: stacks

Question: What are the internal layer of pouches on an etioplast called?
Answer: invaginations

Question: What do angiosperm shoots need to become chloroplasts?
Answer: light

Question: What is required for thylakoids to stack?
Answer: light
Chloroplast

Like mitochondria, chloroplasts use the potential energy stored in an H+, or hydrogen ion gradient to generate ATP energy. The two photosystems capture light energy to energize electrons taken from water, and release them down an electron transport chain. The molecules between the photosystems harness the electrons' energy to pump hydrogen ions into the thylakoid space, creating a concentration gradient, with more hydrogen ions (up to a thousand times as many) inside the thylakoid system than in the stroma. The hydrogen ions in the thylakoid space then diffuse back down their concentration gradient, flowing back out into the stroma through ATP synthase. ATP synthase uses the energy from the flowing hydrogen ions to phosphorylate adenosine diphosphate into adenosine triphosphate, or ATP. Because chloroplast ATP synthase projects out into the stroma, the ATP is synthesized there, in position to be used in the dark reactions.

Question: The energy from the movement of what particles is harnessed to create ATP energy in chloroplasts?
Answer: hydrogen ions

Question: What causes the hydrogen ions in the thylakoid space to move back to the stroma?
Answer: a concentration gradient

Question: Where is the hydrogen ion concentration gradient located?
Answer: inside the thylakoid system

Question: In relation to energy generation, chloroplasts are similar to what in animals?
Answer: mitochondria

Question: To create a concentration gradient, hydrogen ions are moved to where?
Answer: the thylakoid space

Question: Where is the ATP produced in the chloroplast?
Answer: stroma

Question: The concentration gradient runs between the thylakoid space and what?
Answer: the stroma

Question: What is utilized?
Answer: electrons' energy
Chloroplast

The chloroplast membranes sometimes protrude out into the cytoplasm, forming a stromule, or stroma-containing tubule. Stromules are very rare in chloroplasts, and are much more common in other plastids like chromoplasts and amyloplasts in petals and roots, respectively. They may exist to increase the chloroplast's surface area for cross-membrane transport, because they are often branched and tangled with the endoplasmic reticulum. When they were first observed in 1962, some plant biologists dismissed the structures as artifactual, claiming that stromules were just oddly shaped chloroplasts with constricted regions or dividing chloroplasts. However, there is a growing body of evidence that stromules are functional, integral features of plant cell plastids, not merely artifacts.

Question: Which of the following is most common in petals, chromoplasts or amyloplasts?
Answer: chromoplasts

Question: Plant biologists ignored stromule-containing tubules as what?
Answer: artifactual

Question: How do stroma-containing tubules interact with the endoplasmic reticulum?
Answer: branched and tangled with

Question: Who thought that stroma-containing tubules were insignificant?
Answer: some plant biologists

Question: Chloroplast membranes form what if they protrude?
Answer: stroma-containing tubule

Question: Which of the following is most common in roots, chromoplasts or amyloplasts?
Answer: amyloplasts

Question: In what are stromules more common?
Answer: chromoplasts and amyloplasts

Question: What did plant biologist consider stroma-containing tubules to be?
Answer: oddly shaped chloroplasts

Question: Which of the following is not entwined with the endoplasmic reticulum: stromules or roots?
Answer: roots
Chloroplast

Some chloroplasts contain a structure called the chloroplast peripheral reticulum. It is often found in the chloroplasts of C4 plants, though it has also been found in some C3 angiosperms, and even some gymnosperms. The chloroplast peripheral reticulum consists of a maze of membranous tubes and vesicles continuous with the inner chloroplast membrane that extends into the internal stromal fluid of the chloroplast. Its purpose is thought to be to increase the chloroplast's surface area for cross-membrane transport between its stroma and the cell cytoplasm. The small vesicles sometimes observed may serve as transport vesicles to shuttle stuff between the thylakoids and intermembrane space.

Question: what shuttles stuff to the intermembrane ?
Answer: small vesicles

Question: peripheral reticulum is otherwise categorised as what?
Answer: a structure

Question: What is the liquid inside the chloroplast called?
Answer: stromal fluid

Question: What feature of the chloroplast is the chloroplast peripheral reticulum connected to?
Answer: inner chloroplast membrane

Question: Are angiosperms C3 or C4 plants?
Answer: C3

Question: What are the locations that things being transported within the chloroplast are moving between?
Answer: thylakoids and intermembrane space
Chloroplast

The chloroplastidan chloroplasts, or green chloroplasts, are another large, highly diverse primary chloroplast lineage. Their host organisms are commonly known as the green algae and land plants. They differ from glaucophyte and red algal chloroplasts in that they have lost their phycobilisomes, and contain chlorophyll b instead. Most green chloroplasts are (obviously) green, though some aren't, like some forms of Hæmatococcus pluvialis, due to accessory pigments that override the chlorophylls' green colors. Chloroplastidan chloroplasts have lost the peptidoglycan wall between their double membrane, and have replaced it with an intermembrane space. Some plants seem to have kept the genes for the synthesis of the peptidoglycan layer, though they've been repurposed for use in chloroplast division instead.

Question: What supplies the chloroplastidan chloroplasts with nutrients?
Answer: green algae and land plants

Question: What contains chlorophyll b instead of phycobilisomes?
Answer: chloroplastidan chloroplasts

Question: What do algae have?
Answer: chlorophyll

Question: What have  lost their phycobilisomes?
Answer: chloroplastidan chloroplasts

Question: What are repurposed for use in chloropast division?
Answer: genes for the synthesis of the peptidoglycan layer
Chloroplast

Lepidodinium viride and its close relatives are dinophytes that lost their original peridinin chloroplast and replaced it with a green algal derived chloroplast (more specifically, a prasinophyte). Lepidodinium is the only dinophyte that has a chloroplast that's not from the rhodoplast lineage. The chloroplast is surrounded by two membranes and has no nucleomorph—all the nucleomorph genes have been transferred to the dinophyte nucleus. The endosymbiotic event that led to this chloroplast was serial secondary endosymbiosis rather than tertiary endosymbiosis—the endosymbiont was a green alga containing a primary chloroplast (making a secondary chloroplast).

Question: What was replaced with a green derived chloroplast in a dinophyte?
Answer: original peridinin chloroplast

Question: Where do most dinophytes get their chloroplast?
Answer: rhodoplast lineage

Question: Which of the following describes the endosymbiont: serial secondary endosymbiosis or tertiary endosymbiosis?
Answer: serial secondary endosymbiosis

Question: What does Lepidodinium viride have that most most dinophytes lack?
Answer: green algal derived chloroplast

Question: What chloroplast did the serial secondary endosymbiosis produce?
Answer: a green algal derived chloroplast

Question: What function does a green alga have in the process mentioned in this paragraph?
Answer: endosymbiont

Question: What event led to the chloroplast had in lepidodinium?
Answer: serial secondary endosymbiosis
Chloroplast

There are some common misconceptions about the outer and inner chloroplast membranes. The fact that chloroplasts are surrounded by a double membrane is often cited as evidence that they are the descendants of endosymbiotic cyanobacteria. This is often interpreted as meaning the outer chloroplast membrane is the product of the host's cell membrane infolding to form a vesicle to surround the ancestral cyanobacterium—which is not true—both chloroplast membranes are homologous to the cyanobacterium's original double membranes.

Question: What is the main topic of the paragraph?
Answer: common misconceptions about the outer and inner chloroplast membranes

Question: What aspect about chloroplasts is mentioned as being true?
Answer: are surrounded by a double membrane

Question: What creates the vesicle?
Answer: host's cell membrane infolding

Question: What are the chloroplast membranes connected to cyanobacterium's membranes?
Answer: homologous

Question: What is a vesicle?
Answer: the host's cell membrane infolding

Question: Why did people believe the outside membrane is from the host?
Answer: double membrane is often cited as evidence that they are the descendants of endosymbiotic cyanobacteria
Chloroplast

Plastoglobuli were once thought to be free-floating in the stroma, but it is now thought that they are permanently attached either to a thylakoid or to another plastoglobulus attached to a thylakoid, a configuration that allows a plastoglobulus to exchange its contents with the thylakoid network. In normal green chloroplasts, the vast majority of plastoglobuli occur singularly, attached directly to their parent thylakoid. In old or stressed chloroplasts, plastoglobuli tend to occur in linked groups or chains, still always anchored to a thylakoid.

Question: What would a singlular plastoglobuli attached to their parent thylakoid be called?
Answer: plastoglobulus

Question: How were the dense droplets found to be once it was realized they were not roaming free?
Answer: permanently attached either to a thylakoid or to another plastoglobulus attached to a thylakoid

Question: Why are plastoglobuli attached to thylakoid?
Answer: exchange its contents with the thylakoid network

Question: How would a team of dense droplets operate?
Answer: in linked groups or chains

Question: How can you tell if a chloroplast is not young?
Answer: plastoglobuli tend to occur in linked groups or chains
Chloroplast

Embedded in the thylakoid membranes are important protein complexes which carry out the light reactions of photosynthesis. Photosystem II and photosystem I contain light-harvesting complexes with chlorophyll and carotenoids that absorb light energy and use it to energize electrons. Molecules in the thylakoid membrane use the energized electrons to pump hydrogen ions into the thylakoid space, decreasing the pH and turning it acidic. ATP synthase is a large protein complex that harnesses the concentration gradient of the hydrogen ions in the thylakoid space to generate ATP energy as the hydrogen ions flow back out into the stroma—much like a dam turbine.

Question: Which of the following doesn't absorb light energy: chlorophyll, ATP synthase, or carotenoids?
Answer: ATP synthase

Question: Which of the following is smaller, ATP synthase or electrons?
Answer: electrons

Question: Which of the following is not a large protein complex: ATP synthase or chlorophyll?
Answer: chlorophyll
Chloroplast

Chloroplasts are one of many types of organelles in the plant cell. They are considered to have originated from cyanobacteria through endosymbiosis—when a eukaryotic cell engulfed a photosynthesizing cyanobacterium that became a permanent resident in the cell. Mitochondria are thought to have come from a similar event, where an aerobic prokaryote was engulfed. This origin of chloroplasts was first suggested by the Russian biologist Konstantin Mereschkowski in 1905 after Andreas Schimper observed in 1883 that chloroplasts closely resemble cyanobacteria. Chloroplasts are only found in plants and algae.

Question: Who was the biologist that noticed that cyanobacteria and chloroplasts are similar?
Answer: Andreas Schimper

Question: Which is bigger, a eukaryotic cell or the cyanobacterium it engulfed?
Answer: eukaryotic cell

Question: What process are chloroplasts thought to have developed from?
Answer: endosymbiosis

Question: What process is happening to the cyanobacterium as it is engulfed?
Answer: photosynthesizing

Question: The Russian biologist's work followed?
Answer: Andreas Schimper

Question: Which of the following is not an organelle: chloroplasts, cyanobacteria, or mitochondria?
Answer: cyanobacteria

Question: Which of the following does not have chloroplasts: plants, Konstantin Mereschkowski, or algae?
Answer: Konstantin Mereschkowski

Question: What else has an origin that is similar to the origin of chloroplasts?
Answer: Mitochondria
Chloroplast

As a result, chloroplasts in C4 mesophyll cells and bundle sheath cells are specialized for each stage of photosynthesis. In mesophyll cells, chloroplasts are specialized for the light reactions, so they lack rubisco, and have normal grana and thylakoids, which they use to make ATP and NADPH, as well as oxygen. They store CO2 in a four-carbon compound, which is why the process is called C4 photosynthesis. The four-carbon compound is then transported to the bundle sheath chloroplasts, where it drops off CO2 and returns to the mesophyll. Bundle sheath chloroplasts do not carry out the light reactions, preventing oxygen from building up in them and disrupting rubisco activity. Because of this, they lack thylakoids organized into grana stacks—though bundle sheath chloroplasts still have free-floating thylakoids in the stroma where they still carry out cyclic electron flow, a light-driven method of synthesizing ATP to power the Calvin cycle without generating oxygen. They lack photosystem II, and only have photosystem I—the only protein complex needed for cyclic electron flow. Because the job of bundle sheath chloroplasts is to carry out the Calvin cycle and make sugar, they often contain large starch grains.

Question: What gas is required by plants to live?
Answer: CO2

Question: What chemical compound is produced by plants during photosynthesis to be used as an energy source?
Answer: sugar
Chloroplast

Chloroplasts' main role is to conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water. They then use the ATP and NADPH to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, much amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from 1 in algae up to 100 in plants like Arabidopsis and wheat.

Question: What can chloroplasts do besides carrying out photosynthesis?
Answer: fatty acid synthesis, much amino acid synthesis, and the immune response

Question: Which of the following plants has the most chloroplasts per cell: Arabidopsis or algae?
Answer: Arabidopsis

Question: What part of a plant is the immune response carried out in?
Answer: Chloroplasts

Question: Which of the following molecules stores energy: ATP, carbon dioxide or water?
Answer: ATP

Question: Which of the following is not synthesized by plants: amino acids, ATP or water?
Answer: water

Question: What is the term for capturing the sun's energy and converting it to ATP and NADPH?
Answer: photosynthesis

Question: What type of molecule is chlorophyll?
Answer: pigment
Chloroplast

Recently, chloroplasts have caught attention by developers of genetically modified crops. Since, in most flowering plants, chloroplasts are not inherited from the male parent, transgenes in these plastids cannot be disseminated by pollen. This makes plastid transformation a valuable tool for the creation and cultivation of genetically modified plants that are biologically contained, thus posing significantly lower environmental risks. This biological containment strategy is therefore suitable for establishing the coexistence of conventional and organic agriculture. While the reliability of this mechanism has not yet been studied for all relevant crop species, recent results in tobacco plants are promising, showing a failed containment rate of transplastomic plants at 3 in 1,000,000.

Question: How often doesn't the mechanism work?
Answer: at 3 in 1,000,000

Question: How does the biological containment strategy discovered by GMO developers compare to other strategies in terms of contributing to the state of the environment?
Answer: significantly lower environmental risks

Question: What is the practical use case for plastid transformation?
Answer: establishing the coexistence of conventional and organic agriculture

Question: What makes it impossible for genetic information that is found in chloroplasts to be distributed via pollination?
Answer: chloroplasts are not inherited from the male parent

Question: What relatively new strategy could help developers of GMOs establish biologically contained plants?
Answer: plastid transformation

Question: What is controversial?
Answer: genetically modified crops

Question: How can change come upon plants?
Answer: plastid transformation
Chloroplast

After a chloroplast polypeptide is synthesized on a ribosome in the cytosol, an enzyme specific to chloroplast proteins phosphorylates, or adds a phosphate group to many (but not all) of them in their transit sequences. Phosphorylation helps many proteins bind the polypeptide, keeping it from folding prematurely. This is important because it prevents chloroplast proteins from assuming their active form and carrying out their chloroplast functions in the wrong place—the cytosol. At the same time, they have to keep just enough shape so that they can be recognized by the chloroplast. These proteins also help the polypeptide get imported into the chloroplast.

Question: Why is it essential the proteins bind the polypeptide?
Answer: keeping it from folding prematurely

Question: Which of the following does not host phosphate groups, enzymes or transit sequences?
Answer: enzyme

Question: Which is smaller, a ribosome or a polypeptide?
Answer: polypeptide

Question: Which of the following does not perform phosphorylation, enzymes or transit sequences?
Answer: transit sequences

Question: Where doesn't the chloroplast want to carry out their functions?
Answer: the cytosol

Question: What helps the polypeptide get into the cholorplast?
Answer: proteins

Question: What do the proteins have to so the chloroplast knows what they are?
Answer: keep just enough shape

Question: What does folding prematurely do?
Answer: prevents chloroplast proteins from assuming their active form and carrying out their chloroplast functions in the wrong place—the cytosol
Chloroplast

Curiously, around half of the protein products of transferred genes aren't even targeted back to the chloroplast. Many became exaptations, taking on new functions like participating in cell division, protein routing, and even disease resistance. A few chloroplast genes found new homes in the mitochondrial genome—most became nonfunctional pseudogenes, though a few tRNA genes still work in the mitochondrion. Some transferred chloroplast DNA protein products get directed to the secretory pathway (though it should be noted that many secondary plastids are bounded by an outermost membrane derived from the host's cell membrane, and therefore topologically outside of the cell, because to reach the chloroplast from the cytosol, you have to cross the cell membrane, just like if you were headed for the extracellular space. In those cases, chloroplast-targeted proteins do initially travel along the secretory pathway).

Question: Where did chloroplast go?
Answer: mitochondrial genome

Question: What does traveling along the secretory path entail?
Answer: cross the cell membrane

Question: What role do transferred genes have in the immune system?
Answer: disease resistance

Question: What do some chloroplast become?
Answer: nonfunctional pseudogenes

Question: What role does a pseudogene have?
Answer: nonfunctional

Question: Where does the other half of proteins go?
Answer: back to the chloroplast
Chloroplast

Chloroplasts alone make almost all of a plant cell's amino acids in their stroma except the sulfur-containing ones like cysteine and methionine. Cysteine is made in the chloroplast (the proplastid too) but it is also synthesized in the cytosol and mitochondria, probably because it has trouble crossing membranes to get to where it is needed. The chloroplast is known to make the precursors to methionine but it is unclear whether the organelle carries out the last leg of the pathway or if it happens in the cytosol.

Question: An extra step is needed when amino acids are created where?
Answer: the chloroplast

Question: What is unlikely to be incredibly insignificant when it comes to producing amino acids in a Chloroplast?
Answer: stroma

Question: What plant chemical does not have an easy time going to where it must be delivered?
Answer: Cysteine
Chloroplast

Alternatively, glucose monomers in the chloroplast can be linked together to make starch, which accumulates into the starch grains found in the chloroplast. Under conditions such as high atmospheric CO2 concentrations, these starch grains may grow very large, distorting the grana and thylakoids. The starch granules displace the thylakoids, but leave them intact. Waterlogged roots can also cause starch buildup in the chloroplasts, possibly due to less sucrose being exported out of the chloroplast (or more accurately, the plant cell). This depletes a plant's free phosphate supply, which indirectly stimulates chloroplast starch synthesis. While linked to low photosynthesis rates, the starch grains themselves may not necessarily interfere significantly with the efficiency of photosynthesis, and might simply be a side effect of another photosynthesis-depressing factor.

Question: What does the starch do to the thylakoids?
Answer: distorting

Question: How is the starch introduced in the roots?
Answer: glucose monomers in the chloroplast can be linked together