Test Your Knowledge
Eukaryotic Cell Structure
1. True or False: Prokaryotes have nuclei.2. The general term for DNA and associated proteins is (are):
a. Chromosomes
b. Chromatin
c. Chromatone
d. Histone
e. Nucleus
3. What is the advantage of organelles?
4. Which of the following do both eukaryotes and prokaryotes have?
a. Ribosomesb. Nuclei
c. Endoplasmic reticulum
d. Histones
e. Chloroplasts
5. What surrounds each organelle?
Movement in Smaller Eukaryotes and Eukaryotic Cells
1. Which of the following extensions resemble tiny cellular hairs?a. Flagella
b. Cilia
c. Pseudopodia
d. Spikes
e. Bristles
2. True or False: Pseudopodia are permanent cellular extensions.
3. Which cytoskeletal component structures flagella?
a. Microtubules
b. Filaments
c. Microfilaments
d. Actin
e. Pseudopodia
4. What is the difference between eukaryotic and prokaryotic flagella?
5. How do cilia move cells?
Eukaryotic Kingdoms
1. Which of the following kingdoms has all multicellular heterotrophs?a. Protista
b. Fungi
c. Plantae
d. Animalia
e. All kingdoms
2. Which of the following kingdoms has both autotrophic and heterotrophic species?
a. Protista
b. Fungi
c. Plantae
d. Animalia
e. All kingdoms
3. What are two characteristics that separate a jellyfish from a snail?
4. _________________ describes the plant life cycle that produces either spores or gametes.
5. Which of the following kingdoms has chitin in some of its organisms?
a. Protista and Fungi
b. Protista and Plantae
c. Fungi and Animalia
d. Fungi and Plantae
e. Protista and Animalia
Origin of Eukaryotes
1. Which photosynthetic organelle was originally a free-living prokaryote?a. Mitochondria
b. Chloroplast
c. Nucleus
d. Plasma membrane
e. None of the above
2. Approximately how old are eukaryotes?
a. 200 years old
b. 2,000 years old
c. 2 million years old
d. 2 billion years old
e. Unknown
3. Which of the following is not evidence that supports the Endosymbiotic Theory?
a. Double membrane of chloroplasts
b. Chloroplasts contain DNA
c. Chloroplasts contain smaller ribosomes
d. Chloroplasts are green like cyanobacteria
e. None of the above
4.What is the Cambrian Explosion?
5.________ were the eukaryotic kingdom to first colonize land.
Eukaryotes and Environmental Problems
1. What organism causes a red tide?a. Diatoms
b. Dinoflagellates
c. Fungus
d. Rust
e. Plankton
2. How does rust spread?
a. Binary fission
b. Spores
c. Within plant leaves
d. Hyphae
e. Inheritance
3. True or False: Downy mildew has a yellowish brown appearance on leaves.
4. What type of organism causes powdery mildew?
5. True or False: Red tides are caused by the effect high tide in conjunction with human pollution.
Eukaryotic Model Organisms
1. Which of the following organisms likely costs more money to raise?a. Yeast
b. Worms
c. Flies
d. Mice
e. Plants
2. True or False: The best model organism for studying humans is another vertebrate organism.
3. Which of the following model organisms are transparent during development?
a. Arabidopsis and Yeast
b. C. elegans and Mice
c. Zebrafish and C. elegans
d. Zebrafish and Yeast
e. All of the above
4. What model organisms would not be best for studying human diseases in development?
5. Cell fate is when a cell's final differentiated state has already been determined. Why is C. elegans a good model system for studying cell fate?
Possible Answers
Eukaryotic Cell Structure
1. True or False: Prokaryotes have nuclei. False. If you remember nothing else in life, remember this. Actually, remember to wash your hands, too.2. The general term for DNA and associated proteins is (are):
b. Chromatin
Chromosomes are one whole piece of chromatin, which is DNA and proteins (histones).
3. What is the advantage of organelles?
They allow the separation and compartmentalization of processes. Cells can then be bigger and perform more functions than smaller prokaryotic cells.
4. Which of the following do both eukaryotes and prokaryotes have?
a. Ribosomes
Everybody's gotta make proteins, and ribosomes are the only place to do it. But while prokaryotic ribosomes are only in the cell's cytoplasm, eukaryotic ribosomes can be found in the cytoplasm or studding the rough endoplasmic reticulum like 1000 piercings.
5. What surrounds each organelle?
A membrane—it keeps each organelle nice and tidy, defined in its own little space.
Movement in Smaller Eukaryotes and Eukaryotic Cells
1. Which of the following extensions resemble tiny cellular hairs?b. Cilia
Cells that have cilia usually have a good number of them, and they resemble a short spikey hairdo.
2. True or False: Pseudopodia are permanent cellular extensions.
False. The nice thing about pseudopodia is that they are temporary, and cells can re-make and re-shape these fake feet depending on their fancy.
3. Which cytoskeletal component structures flagella?
a. Microtubules
While pseudopodia can be made up of different types of cytoskeletal components, flagella (and cilia) are made of a defined "9 plus 2" arrangement of microtubules cellophane in a plasma membrane.
4. What is the difference between eukaryotic and prokaryotic flagella?
Both flagella are used to "do the locomotion," but eukaryotic flagella whip back and forth while prokaryotic flagella spin clockwise or counterclockwise through the help of some motor proteins. Prokaryotic flagella also aren't made up of microtubules.
5. How do cilia move cells?
Some cilia on single-celled organisms do help them move a little bit. Cilia on stationary cells move the fluid around them, as if splashing around in the bath. Hey, if you can't move, you might as well change the space around you, right?
Eukaryotic Kingdoms
1. Which of the following kingdoms has all multicellular heterotrophs?d. Animalia
The Animal Kingdom. All animals are multicellular and heterotrophs. Other kingdoms have heterotrophs (like Fungi and Protista), but they aren't all multicellular.
2. Which of the following kingdoms has both autotrophic and heterotrophic species?
a. Protista
Protista has the duality of both autotrophic and heterotrophic species that either make or eat food, respectively. Fungi and Animalia are all heterotrophs, while all Plantae are autotrophs.
3. What are two characteristics that separate a jellyfish from a snail?
Jellyfish are made of jelly. Just kidding. Jellyfish have radial symmetry, while snails have bilateral symmetry. Snails are also protostomes. Jellyfish aren't grouped as protostomes, since they have no bilateral symmetry. Snails also have a nifty exoskeleton.
4. _________________ describes the plant life cycle that produces either spores or gametes.
Alternating generations—like switching between black and red on a checkerboard.
5. Which of the following kingdoms has chitin in some of its organisms?
a. Protista and Fungi
b. Protista and Plantae
c. Fungi and Animalia
d. Fungi and Plantae
e. Protista and Animalia
Fungal cell walls are often composed of a sugar-derivative polymer known as chitin. Some animals have chitin in their exoskeleton, like lobsters and crabs. Plants have cell walls like fungi, but there's no chitin in those.
Origin of Eukaryotes
1. Which photosynthetic organelle was originally a free-living prokaryote?b. Chloroplast
Although the mitochondrion is another organelle that was most likely a free-living bacterium, it can't perform the big trick of turning sunlight into food. A chloroplast can perform photosynthesis.
2. Approximately how old are eukaryotes?
d. 2 billion years old
Although more complicated eukaryotes are more recent, the first ones appeared a few billion years ago.
3. Which of the following is not evidence that supports the Endosymbiotic Theory?
d. Chloroplasts are green like cyanobacteria
Chloroplasts look like their own cell, complete with their own DNA and prokaryotic ribosomes and a double membrane. This supports the idea that chloroplasts could have been obtained when being engulfed by another cell, which is Endosymbiotic Theory. It's true that chloroplasts are green and that they probably originated from cyanobacteria, but color isn't really a good supporting factor. They are both green because of the pigment chlorophyll, but that fact doesn't really prove that one invaded the other. After all, Kermit the frog is green but not photosynthetic.
4.What is the Cambrian Explosion?
The Cambrian Explosion describes when Earth's diversity in eukaryotes literally exploded in numbers. It isn't when the eukaryotes first made their appearance, but it is when they started getting creative.
5.________ were the eukaryotic kingdom to first colonize land.
Plants! You probably have a mental image of plants tiptoeing with their roots up onto the beach. We do, too. Coulda' happened. But probably not. Most likely, the wind and water distributed seeds and small plants onto the sand where they gradually took root.
Eukaryotes and Environmental Problems
1. What organism causes a red tide?b. Dinoflagellates
Though rust is reddish, it's not the cause of the red tide. The red tide is a little of a misnomer, because it can be caused by the overgrowth of red dinoflagellates, but these organisms can also be a wide range of other colors.
2. How does rust spread?
b. Spores
Spores are carried in the wind, from one plant to another. Although spores fall on plant leaves, this is how they invade a plant, forming hyphae that reach into a plant leaf and grab hold.
3. True or False: Downy mildew has a yellowish brown appearance on leaves.
True. Downy mildew is slimy like laundry detergent, causing leaves to turn color and eventually brown due to decay and death.
4. What type of organism causes powdery mildew?
Fungi cause powdery mildew, although downy mildew are caused by fungi-like posers.
5. True or False: Red tides are caused by the effect high tide in conjunction with human pollution.
False. There is no evidence that tides actually cause red tides, although human pollution can. Remember, though, that some red tides are just a part of the ocean's natural cycle.
Eukaryotic Model Organisms
1. Which of the following organisms likely costs more money to raise?d. Mice
So while all of these model organisms are "relatively" inexpensive, it's just that they are "relatively" inexpensive when compared to an alternative. But let's face it, itsy bitsy yeast are really cheap, while mice eat more and take up more space, making them costlier.
2. True or False: The best model organism for studying humans is another vertebrate organism.
False. We mean, sure, sometimes that's the better choice, but it depends. Are we asking about something that another vertebrate would best relate to, like heart disease? Or are we asking what role RNA Polymerase III has on translation?
3. Which of the following model organisms are transparent during development?
c. Zebrafish and C. elegans
Who's see-through like a piece of saran wrap? Zebrafish might be transparent once they look like zebras, but while the embryos are developing, they are as clear as a C. elegans worm. Yeast aren't that opaque, but they aren't cellophane either, and they don't exactly go through the process of development.
4. What model organisms would not be best for studying human diseases in development?
Yeast and Plants.
Because yeast and plants don't develop arms and legs and heads and organs and all that jazz, they aren't the best model organisms for human and animal development.
5. Cell fate is when a cell's final differentiated state has already been determined. Why is C. elegans a good model system for studying cell fate?
The cell fate of every single cell in C. elegans has been mapped, meaning we know exactly what each one is going to be when it "grows up." That makes it easy to make a mutation and then see what goes wrong and where.