1. Watch this Video

2a. Read This: A few useful terms and concepts that didn’t (explicitly) make it into the video

Symbiosis means “living together.” It’s a term that we’ll look at in detail in Unit 8 (Ecology). When one organism lives inside another it’s called endosymbiosis. The endosymbiotic relationship that you might be familiar with is parasitism, in which a parasite (like a tapeworm) lives inside a host (like a dog or a person). The parasite benefits and the host is harmed.
Endosymbiosis can also be positive. For example, the giant green sea anemone has, living inside its tissues, an endosymbiotic algae. The algae carries out photosynthesis, and the anemone benefits from the glucose that the algae makes. The algae, in turn, gets a safe place to live. This type of win-win relationship is called mutualism. We’ll see below how mitochondria and chloroplasts arose as endosymbiotic mutualists.
All of life can be organized into three domains.
- Bacteria: Single-celled prokaryotes with no nucleus, known for diverse metabolic pathways and widespread presence in various environments.
- Archaea: Single-celled prokaryotes similar to bacteria but with unique cell membranes and metabolic pathways, often thriving in extreme environments.
- Eukarya: Organisms with eukaryotic cells that have a nucleus and membrane-bound organelles, ranging from single-celled protists to multicellular plants, animals, and fungi.

2b. Study this Summary

Introduction:

Cellular compartmentalization refers to the division of a cell into distinct internal regions. This organization is crucial for the function and efficiency of eukaryotic cells.

Eukaryotic compartmentalization arose in an astonishing way: through a process called endosymbiosis, in which an archaeal cell fused with a bacterial cell.

What is Cell Compartmentalization?

Definition: Internal division of the internal volume of a cell into specialized sections.
Advantages:
- Allows for the creation of cellular regions with a distinct internal chemistry. For example, lysosomes house hydrolytic enzymes used during various digestive and recycling processes. To keep the rest of the cell safe, these enzymes (which would otherwise digest the cell) are kept within a membrane-bound lysosome.
- Increases internal working surface area for various membrane-associated processes. (e.g., membrane-bound enzymes in the ER and ribosomes in the rough ER).
- Creates protected zones within the cell that are shielded from the metabolic activity of the cytoplasm. The nucleus is one such protected zone.

Comparison of Compartmentalization in Prokaryotic and Eukaryotic Cells:

Prokaryotic Cells: Few compartments, but there are specialized regions like the thylakoids in cyanobacteria, which are essential for photosynthesis. Note that this same structure is seen in chloroplasts (which evolved from cyanobacteria).
Eukaryotic Cells: Highly compartmentalized with many membrane-bound organelles (e.g., lysosomes, ER, Golgi complex, and vacuoles) that have distinct functions and structures.

The Endomembrane System:

A connected, dynamic network of internal membranes, including:
- Nuclear membrane, rough ER, smooth ER, Golgi complex, lysosomes, and vesicles.
Membrane components flow and exchange phospholipids dynamically between compartments.

Origin of Eukaryotic Cells and Organelles:

Timeline: Eukaryotes arose ~1.8 billion years ago through endosymbiosis:
How it Happened:
- An archaeal cell took up a bacterial cell. The bacterial cell evolved into the mitochondria. The archaeal cell, with its new endosymbiont, was the common ancestor of all eukaryotes.
- A second endosymbiotic event led to the formation of chloroplasts, which evolved from cyanobacteria that were taken up from an early eukaryotic cell.
Evidence for Endosymbiosis:
- Mitochondria and chloroplasts have many bacterial features, including
  - Circular DNA
  - Replicate via binary fission
  - Ribosomes that are similar in structure to those in bacteria
  - Synthesis of some of their own proteins.
- Both organelles reproduce themselves independently from their host cell through binary fission (which is how bacteria reproduce themselves)
- Both organelles have double membranes, with the outer membrane originating from the host cell that took up the endosymbiotic ancestor of mitochondria or chloroplasts.

3. Master these Flashcards

[qdeck bold_text=”false” qrecord_id=”sciencemusicvideosMeister1961-Cellular Compartmentalization and Endosymbiosis Flashcards, APBVP”]

[h]Cellular Compartmentalization and its Origins

[i]

[q]What is cellular compartmentalization?
[a]Cellular compartmentalization is a kind of cellular organization that divides the internal volume of the cell into discrete (but often interconnected) compartments. These compartments each have distinct properties and functions.

[q]List some examples of cellular compartmentalization.
[a]Examples of cellular compartmentalization include the entire endomembrane system (nucleus, rough and smooth E.R., Golgi, lysosomes, transport vesicles), small vacuoles, the large central vacuole in plant cells, mitochondria, chloroplasts, and plastids).

[q]In terms of cellular compartmentalization, how do the three domains differ?
[a]Cellular compartmentalization is only widespread in Domain Eukarya.

[q]Define endosymbiosis.
[a]Endosymbiosis is a biological relationship in which one species lives inside another.

[q]Which two eukaryotic organelles are endosymbiotic mutualists?
[a]The two endosymbiotic mutualists in eukaryotic cells are mitochondria (found in all eukaryotic cells) and chloroplasts (found in plants, algae, and other aquatic photosynthetic single-celled eukaryotes).

[q]Describe the mutualistic relationship between eukaryotic cells, mitochondria, and chloroplasts.
[a]All eukaryotic cells benefit from their relationship with mitochondria because they receive ATP (the molecule that cells use to perform any kind of cellular work) from their mitochondria. The mitochondria benefit because they receive food from their host cells, as well as a safe place to live.

Plant and algae cells benefit from their relationship with chloroplasts because the chloroplasts perform photosynthesis, enabling them to provide their host cells with food in the form of secreted glucose. The chloroplasts get a safe place to live.

[q]What’s the evidence supporting the claim that mitochondria and chloroplasts were once independent cells?
[a]

Both mitochondria and chloroplasts have a double membrane.
Mitochondria and chloroplasts have their own DNA, and this DNA has the same form (a looped chromosome) as the DNA that’s found in bacteria.
Both mitochondria and chloroplasts have their own ribosomes and produce some of their own proteins. These ribosomes are similar to those found in bacteria.
Both mitochondria and chloroplasts replicate themselves (independently of the host cell’s cell cycle).

[q]What is the endomembrane system?
[a]The endomembrane system is a dynamic network of membranes within a eukaryotic cell that includes the nuclear membrane, rough ER, smooth ER, Golgi complex, lysosomes, and vesicles.

[q]What are the advantages of cellular compartmentalization?
[a]Advantages include:

Maintaining distinct internal environments for chemical reactions (e.g., lysosomes with acidic pH).
Increased surface area for reactions, such as the membranes of the ER and Golgi complex.
Creating protected areas such as the nucleus, which shields the DNA and processes like DNA replication or transcription from the metabolic activity in the cytoplasm.

[q]What role did endosymbiosis play in the origin of mitochondria and chloroplasts?
[a]Mitochondria were once independent prokaryotic organisms that were taken up by an archaeal host. Later, a chloroplast was similarly taken up by an early eukaryotic cell (that already contained mitochondria)

[q]Why is the double membrane of mitochondria and chloroplasts significant?
[a]The double membrane is evidence of their endosymbiotic origin, with the outer membrane derived from the archael cell and the inner membrane from the original prokaryote.

[/qdeck]

4. Tackle these Quizzes

4.1 The Endomembrane System

[qwiz random = “true” qrecord_id=”sciencemusicvideosMeister1961-The Endomembrane System, APBVP”]

[h]The Endomembrane System

[i]

[q]Which number is pointing to the nucleus?

[textentry single_char=”true”]

[c]MQ ==[Qq]

[f]WWVzLiBUaGUgbnVjbGV1cywgdGhlIGNlbGwmIzgyMTc7cyBjb250cm9sIGNlbnRlciwgaXMgYXQgbnVtYmVyIDE=[Qq]

[c]Kg==[Qq]

[f]Tm8uIEZpbmQgdGhlIHN0cnVjdHVyZSB0aGF0JiM4MjE3O3MgY2xvc2VzdCB0byB0aGUgY2VudGVyIG9mIHRoZSBjZWxsIChmdXJ0aGVzdCBmcm9tIHRoZSBtZW1icmFuZS4=

Cg==

[Qq]

[q]Which number is pointing to the rough E.R?

[textentry single_char=”true”]

[c]Mg ==[Qq]

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[c]Kg==[Qq]

[f]Tm8uwqBZb3UmIzgyMTc7cmUgbG9va2luZyBmb3IgdGhlIHJvdWdoIEVSLiBGaW5kIHJpYm9zb21lcyAoYmxhY2sgZG90cykgYXR0YWNoZWQgdG8gbWVtYnJhbmUu

Cg==

[Qq]

[q]What number is pointing to the smooth E.R?

[textentry single_char=”true”]

[c]Mw ==[Qq]

[f]WWVzLiAmIzgyMjA7MyYjODIyMTsgaXMgdGhlIHNtb290aMKgRVIsIHdoaWNoIGlzIHdoZXJlwqBtZW1icmFuZSAoYW5kIG90aGVyIGxpcGlkcykgYXJlIHN5bnRoZXNpemVkLg==[Qq]

[c]Kg==[Qq]

[f]Tm8uIFlvdSYjODIxNztyZSBsb29raW5nIGZvciB0aGUgc21vb3RoIEVSLCB3aGljaCBpcyBhIG5ldHdvcmsgb2YgbWVtYnJhbmVzIGp1c3Qgb3V0c2lkZSBvZiB0aGUgcm91Z2ggRVIsIGFuZCB3aGljaCBsYWNrcyByaWJvc29tZXMu

Cg==

[Qq]

[q]Which numbered part indicates a vesicle that’s moving between the ER and the Golgi?

[textentry single_char=”true”]

[c]NA ==[Qq]

[f]WWVzLiAmIzgyMjA7NCYjODIyMTsgaXMgYSB2ZXNpY2xlLCBhIGJ1YmJsZSBvZiBtZW1icmFuZSwgdGhhdCYjODIxNztzIHRyYW5zcG9ydGluZyBhIHByb3RlaW4gZnJvbSB0aGUgRVIgdG8gdGhlIEdvbGdpIGFwcGFyYXR1cy4=[Qq]

[c]Kg==[Qq]

[f]Tm8uIExvb2sgZm9yIGEgc21hbGwgYnViYmxlIG9mIG1lbWJyYW5lIGluLWJldHdlZW4gdGhlIEVSIGFuZCB0aGUgR29sZ2ku

Cg==

[Qq]

[q]The Golgi modifies proteins that are synthesized in the Rough E.R. Which number indicates the Golgi?

[textentry single_char=”true”]

[c]NQ ==[Qq]

[f]WWVzLiAmIzgyMjA7NSYjODIyMTsgaXMgdGhlIEdvbGdpIGFwcGFyYXR1cy4gV2l0aGluIHRoZXNlIGZsYXR0ZW5lZCBzYWNzIG9mIG1lbWJyYW5lLCBlbnp5bWVzIG1vZGlmeSBwcm90ZWlucyBhbmQgcHJlcGFyZSB0aGVtIGZvciBzaGlwcGluZyB0byB0aGVpciBmaW5hbCBkZXN0aW5hdGlvbi4=[Qq]

[c]Kg==[Qq]

[f]Tm8uIExvb2sgZm9yIHRoZSBzZXJpZXMgb2YgZmxhdHRlbmVkIHNhY3MgYmV0d2VlbiB0aGUgbWVtYnJhbmUgYW5kIHRoZSBFUi4=

Cg==

[Qq]

[q]After modification of a protein, the Golgi might bud off a vesicle that will bring a protein to the membrane for export from the cell. Which number shows a vesicle that’s budding off from the Golgi complex?

[textentry single_char=”true”]

[c]Ng ==[Qq]

[f]WWVzLiAmIzgyMjA7NiYjODIyMTsgc2hvd3MgYSB2ZXNpY2xlIHRoYXQmIzgyMTc7cyBidWRkaW5nIG9mZiBmcm9tIHRoZSBHb2xnaS4=[Qq]

[c]Kg==[Qq]

[f]Tm8uwqBGaW5kIHRoZSB2ZXNpY2xlIGp1c3Qgb3V0c2lkZSB0aGUgR29sZ2kgYm9keSwgaW4gYmV0d2VlbiB0aGUgR29sZ2kgYW5kIHRoZSBtZW1icmFuZSAoYW5kIGRvbiYjODIxNzt0IHBpY2sgIyA3KS4=

Cg==

[Qq]

[x][restart]

[/qwiz]

4.2. The Origins of Cellular Compartmentalization

[qwiz qrecord_id=”sciencemusicvideosMeister1961-Cellular Compartmentalization and its Origins, APBVP”]

[h]Cellular Compartmentalization and its Origins

[i]Mitochondria

Making ATP

Setting the stage for

Life’s complexity

[q] Organelles like the mitochondria, the Golgi, and lysosomes are all examples of cellular [hangman].

[c]IGNvbXBhcnRtZW50YWxpemF0aW9u[Qq]

[f]IENvcnJlY3Qh[Qq]

[q] The only domain in which extensive cellular compartmentalization is found is domain [hangman].

[c]ZXVrYXJ5YQ==[Qq]

[f]IEV4Y2VsbGVudCE=[Qq]

[q]Cells that lack a nucleus or other membrane-bound compartments are described as [hangman]

[c]cHJva2FyeW90aWM=[Qq]

[q]The cell type found in animals, plants, fungi, and many single-celled organisms with large complex cells is described as [hangman].

[c]ZXVrYXJ5b3RpYw==[Qq]

[q]A relationship in which one organism lives inside one another is called [hangman].

[c]ZW5kb3N5bWJpb3Npcw==[Qq]

[q]A symbiotic relationship in which both organisms benefit is called [hangman].

[c]bXV0dWFsaXNt[Qq]

[q]Mitochondria can be thought of as [hangman] endosymbionts living within every [hangman] cell. The mitochondria supply their hosts with [hangman]. In return, the mitochondria receive [hangman] and oxygen.

[c]bXV0dWFsaXN0aWM=[Qq]

[c]ZXVrYXJ5b3RpYw==[Qq]

[c]QVRQ[Qq]

[c]Zm9vZA==[Qq]

[q]In most theories about the origin of mitochondria, the cell that took up the mitochondria would have belonged to the domain [hangman].

[c]YXJjaGFlYQ==[Qq]

[q]Evidence for the endosymbiotic origins of mitochondria and chloroplasts includes the fact that both mitochondria and chloroplasts have a [hangman] membrane; that both possess their own [hangman], which is organized into a looped [hangman]; and that both can [hangman] by binary fission, just like bacteria.

[c]ZG91Ymxl[Qq]

[c]RE5B[Qq]

[c]Y2hyb21vc29tZQ==[Qq]

[c]cmVwcm9kdWNl[Qq]

[q] The diagram below depicts how eukaryotic cells might have first evolved through endosymbiosis. In this model, the cell that evolved into a mitochondrion must be the one at number

[textentry single_char=”true”]

[c]ID I=[Qq]

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[c]IEVudGVyIHdvcmQ=[Qq]

[c]ICo=[Qq]

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[q]The diagram below depicts how eukaryotic cells might have first evolved through endosymbiosis. In the diagram below, an archaeal cell is shown at

[textentry single_char=”true”]

[c]ID E=[Qq]

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[c]IEVudGVyIHdvcmQ=[Qq]

[c]ICo=[Qq]

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[q]What is the primary advantage of cellular compartmentalization in eukaryotic cells?
[c]VG8gY3JlYXRlIHNwZWNpYWxpemVkIGludGVybmFsIGVudmlyb25tZW50cyBmb3IgZGlmZmVyZW50IHByb2Nlc3Nlcy4=[Qq]
[f]UGFydGlhbGx5IGNvcnJlY3QhIFRoaXMgaXMgb25lIG9mIHRoZSBhZHZhbnRhZ2VzLCBidXQgdGhlcmUgYXJlIG1vcmUu[Qq]
[c]VG8gYWxsb3cgY2VsbHMgdG8gbWFpbnRhaW4gZGlzdGluY3QgaW50ZXJuYWwgY2hlbWlzdHJ5Lg==[Qq]
[f]UGFydGlhbGx5IGNvcnJlY3QhIFRoaXMgaXMgb25lIGFkdmFudGFnZSwgYnV0IGl0JiM4MjE3O3Mgbm90IHRoZSBmdWxsIGFuc3dlci4=[Qq]
[c]VG8gaW5jcmVhc2Ugc3VyZmFjZSBhcmVhIGZvciBjZWxsdWxhciBwcm9jZXNzZXMu[Qq]
[f]UGFydGlhbGx5IGNvcnJlY3QhIFRoaXMgaXMgb25lIGJlbmVmaXQsIGJ1dCBpdCYjODIxNztzIG5vdCB0aGUgY29tcGxldGUgYW5zd2VyLg==[Qq]
[c]QWxsIG9mIHRo ZSBhYm92ZS4=[Qq]
[f]Q29ycmVjdCEgQ2VsbHVsYXIgY29tcGFydG1lbnRhbGl6YXRpb24gcHJvdmlkZXMgYWxsIHRoZXNlIGJlbmVmaXRzLg==

Cg==[Qq]

[q]Which of the following is a mutualistic relationship involving endosymbiosis?
[c]QSB0YXBld29ybSBsaXZpbmcgaW4gYSBkb2cu[Qq]
[f]Tm8sIHRoaXMgaXMgYW4gZXhhbXBsZSBvZiBwYXJhc2l0aXNtLCB3aGVyZSBvbmUgb3JnYW5pc20gYmVuZWZpdHMgYW5kIHRoZSBvdGhlciBpcyBoYXJtZWQu[Qq]
[c]UGhvdG9zeW50aGV0aWMgYWxnYWUgbGl2aW5nIGluc2lkZSB0aGUg dGlzc3VlcyBvZiBhIGdpYW50IGdyZWVuIHNlYSBhbmVtb25lLg==[Qq]
[f]Q29ycmVjdCEgQm90aCB0aGUgYWxnYWUgYW5kIHRoZSBhbmVtb25lIGJlbmVmaXQsIG1ha2luZyB0aGlzIGFuIGV4YW1wbGUgb2YgbXV0dWFsaXNtLg==[Qq]
[c]QSBiYWN0ZXJpdW0gaW5mZWN0aW5nIGEgaHVtYW4gY2VsbC4=[Qq]
[f]Tm8sIHRoaXMgaXMgbm90IG11dHVhbGlzbTsgaXQmIzgyMTc7cyBwYXJhc2l0aXNtLg==[Qq]
[c]QSB2aXJ1cyByZXBsaWNhdGluZyB3aXRoaW4gYSBob3N0IGNlbGwu[Qq]
[f]Tm8sIHRoaXMgaXMgbm90IG11dHVhbGlzbTsgdmlydXNlcyBhcmUgaW50cmFjZWxsdWxhciBwYXJhc2l0ZXMu

Cg==[Qq]

[q]Which domain includes organisms with highly compartmentalized cells?
[c]QmFjdGVyaWE=[Qq]
[f]Tm8sIGJhY3RlcmlhIGFyZSBwcm9rYXJ5b3RlcyBhbmQgbGFjayBjb21wYXJ0bWVudGFsaXphdGlvbi4=[Qq]
[c]QXJjaGFlYQ==[Qq]
[f]Tm8sIGFyY2hhZWEgYXJlIHByb2thcnlvdGVzIHdpdGhvdXQgY29tcGFydG1lbnRhbGl6YXRpb24u[Qq]
[c]RXVrYX J5YQ==[Qq]
[f]Q29ycmVjdCEgRXVrYXJ5b3RlcyBoYXZlIGNvbXBsZXggY2VsbHMgd2l0aCBjb21wYXJ0bWVudGFsaXplZCBzdHJ1Y3R1cmVzLg==

Cg==[Qq]

[q]Which of the structures below is or are part of the endomembrane system?
[c]VGhlIGNlbGwgd2FsbCBhbmQgcGxhc21hIG1lbWJyYW5lLg==[Qq]
[f]Tm8sIHRoZSBjZWxsIHdhbGwgaXMgbm90IHBhcnQgb2YgdGhlIGVuZG9tZW1icmFuZSBzeXN0ZW0u[Qq]
[c]Q2hsb3JvcGxhc3RzIGFuZCBtaXRvY2hvbmRyaWEu[Qq]
[f]Tm8sIHRoZXNlIG9yZ2FuZWxsZXMgYXJlIG5vdCBwYXJ0IG9mIHRoZSBlbmRvbWVtYnJhbmUgc3lzdGVtOyB0aGV5IGFyZSBkZXJpdmVkIGZyb20gZW5kb3N5bWJpb3Npcy4=[Qq]
[c]VGhlIG51Y2xlYXIgbWVtYnJhbmUsIEVSLCBHb2xnaSBj b21wbGV4LCBseXNvc29tZXMsIGFuZCB2ZXNpY2xlcy4=[Qq]
[f]Q29ycmVjdCEgVGhlc2Ugc3RydWN0dXJlcyBhcmUgYWxsIHBhcnQgb2YgdGhlIGR5bmFtaWMgZW5kb21lbWJyYW5lIHN5c3RlbS4=[Qq]
[c]Umlib3NvbWVzIGFuZCBwbGFzbWlkcy4=[Qq]
[f]Tm8uIFJpYm9zb21lcyBhcmUgaW50cmFjZWxsdWxhciBzdHJ1Y3R1cmVzIHRoYXQgdHJhbnNsYXRlIG1STkEgaW50byBwcm90ZWluLiBQbGFzbWlkcyBhcmUgbG9vcHMgb2YgRE5BIHVzZWQgZHVyaW5nIGJhY3RlcmlhbCBnZW5lIHRyYW5zZmVyIChjb25qdWdhdGlvbikuIEhpbnQ6IHBhcnRzIG9mIHRoZSBlbmRvbWVtYnJhbmUgc3lzdGVtIGFyZSBzdXJyb3VuZGVkIGJ5IG1lbWJyYW5lLg==

Cg==[Qq]

[q]What is the term for when an organism lives inside another organism?

[c]U3ltYmlvc2lz[Qq]
[f]Q2xvc2UsIGJ1dCBzeW1iaW9zaXMgaXMgYSBicm9hZGVyIHRlcm0gdGhhdCBpbmNsdWRlcyBsaXZpbmcgdG9nZXRoZXIgaW4gZ2VuZXJhbC4=[Qq]
[c]UGFyYXNpdGlzbQ==[Qq]
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[c]RW5kb3N5bW Jpb3Npcw==[Qq]
[f]Q29ycmVjdCEgRW5kb3N5bWJpb3NpcyBkZXNjcmliZXMgb25lIG9yZ2FuaXNtIGxpdmluZyBpbnNpZGUgYW5vdGhlci4=[Qq]
[c]TXV0dWFsaXNt[Qq]
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Cg==[Qq]

[q]Which feature of mitochondria and chloroplasts supports the endosymbiosis theory?
[c]VGhleSBoYXZlIHRoZWlyIG 93biBjaXJjdWxhciBETkEu[Qq]
[f]Q29ycmVjdCEgVGhpcyBmZWF0dXJlIGlzIGV2aWRlbmNlIG9mIHRoZWlyIHByb2thcnlvdGljIG9yaWdpbi4=[Qq]
[c]VGhleSBhcmUgZm91bmQgaW4gYWxsIHRocmVlIGRvbWFpbnMu[Qq]
[f]Tm8sIG1pdG9jaG9uZHJpYSBhbmQgY2hsb3JvcGxhc3RzIGFyZSBvbmx5IGZvdW5kIGluIGV1a2FyeW90ZXMu[Qq]
[c]VGhleSBkbyBub3QgaGF2ZSBtZW1icmFuZXMu[Qq]
[f]Tm8sIGJvdGggaGF2ZSBtZW1icmFuZXMsIHdoaWNoIGlzIGFsc28ga2V5IHRvIHRoZWlyIGVuZG9zeW1iaW90aWMgb3JpZ2luLg==[Qq]
[c]VGhleSByZWx5IHNvbGVseSBvbiB0aGUgaG9zdCBjZWxsIGZvciBwcm90ZWlucy4=[Qq]
[f]Tm8sIHRoZXkgcHJvZHVjZSBzb21lIG9mIHRoZWlyIG93biBwcm90ZWlucywgd2hpY2ggc3VwcG9ydHMgdGhlIGVuZG9zeW1iaW9zaXMgdGhlb3J5Lg==

Cg==[Qq]

[q]What key event in evolution allowed eukaryotic cells to form chloroplasts?
[c]VGhlIGZ1c2lvbiBvZiB0d28gcHJva2FyeW90aWMgY2VsbHMu[Qq]
[f]Tm8uIFRoYXQmIzgyMTc7cyBjbG9zZXIgdG8gYW4gZXhwbGFuYXRpb24gb2YgdGhlIG9yaWdpbiBvZiBtaXRvY2hvbmRyaWEgKGFuZCBldWthcnlvdGVzIGluIGdlbmVyYWwp[Qq]
[c]QW4gZWFybHkgZXVrYXJ5b3RpYyBjZWxsICh3aXRoIGEgbnVjbGV1cyBhbmQgbWl0b2No b25kcmlhKSBlbmd1bGZpbmcgYSBwaG90b3N5bnRoZXRpYyBiYWN0ZXJpYWwgY2VsbC4=[Qq]
[f]Q29ycmVjdCEgVGhpcyBlbmRvc3ltYmlvdGljIGV2ZW50IGdhdmUgcmlzZSB0byBjaGxvcm9wbGFzdHMu[Qq]
[c]VGhlIGNyZWF0aW9uIG9mIHRoZSBlbmRvbWVtYnJhbmUgc3lzdGVtLg==[Qq]
[f]Tm8sIHRoZSBlbmRvbWVtYnJhbmUgc3lzdGVtIGlzIGEgc2VwYXJhdGUgaW5ub3ZhdGlvbiBpbiBldWthcnlvdGljIGNlbGxzLg==[Qq]
[c]QSBtdXRhdGlvbiBpbiB0aGUgaG9zdCBjZWxsJiM4MjE3O3MgRE5BLg==[Qq]
[f]Tm8sIHRoZSBvcmlnaW4gb2YgY2hsb3JvcGxhc3RzIGludm9sdmVkIGVuZG9zeW1iaW9zaXMsIG5vdCBtdXRhdGlvbi4=

Cg==[Qq]

[q]Which of the following is NOT a component of the endomembrane system?
[c]Um91Z2ggRVI=[Qq]
[f]Tm8sIHRoZSByb3VnaCBFUiBpcyBhIGtleSBjb21wb25lbnQgb2YgdGhlIGVuZG9tZW1icmFuZSBzeXN0ZW0u[Qq]
[c]R29sZ2kgY29tcGxleA==[Qq]
[f]Tm8sIHRoZSBHb2xnaSBjb21wbGV4IGlzIHBhcnQgb2YgdGhlIGVuZG9tZW1icmFuZSBzeXN0ZW0u[Qq]
[c]THlzb3NvbWVz[Qq]
[f]Tm8sIGx5c29zb21lcyBhcmUgcGFydCBvZiB0aGUgZW5kb21lbWJyYW5lIHN5c3RlbS4=[Qq]
[c]TWl0b2No b25kcmlh[Qq]
[f]Q29ycmVjdCEgTWl0b2Nob25kcmlhIGFyZSBub3QgcGFydCBvZiB0aGUgZW5kb21lbWJyYW5lIHN5c3RlbTsgdGhleSBhcmUgZGVyaXZlZCBmcm9tIGVuZG9zeW1iaW9zaXMu

Cg==[Qq]

[x][restart]

[/qwiz]

What’s next?

Please proceed to this next tutorial: Eukaryotic Cell Parts and Functions