ch 24, 25, 27, 28, 29, and 30

A biologist draws a tree of life having only three branches. Which groups did the biologist most likely choose for her diagram? vertebrates, Bacteria, and Archaea Bacteria, fungi, and Archaea Eukarya, Bacteria, and fungi fungi, Eukarya, and vertebrates Archaea, Bacteria, and Eukarya

Archaea, Bacteria, and Eukarya

Which of the statements is a key advantage of eukaryotic cells over prokaryotic cells? None of the other answer options is correct. Eukaryotic cells have a rigid cytoskeleton, which allows them to withstand greater stress. Eukaryotic cells have a cell membrane, which allows them to ship materials into and out of the cell. Eukaryotic cells have a flexible cytoskeleton, which allows them to change shape and gives them the ability to engulf other materials. Eukaryotic cells have ribosomes, which allow them to make more complex proteins.

Eukaryotic cells have a flexible cytoskeleton, which allows them to change shape and gives them the ability to engulf other materials.

Consider the image. In the figure shown, which letter indicates part or parts of the plant composed of all three of the main tissue types? F E A B D C

F

Imagine you are talking to your friend who is very excited because he has just transduced his first batch of bacteria in the laboratory. What does this mean? He introduced a gene of interest into his bacteria by lysing other bacterial cells and exposing his bacteria to this mixture. He introduced a gene of interest into his bacteria using other bacterial species that can form pili. Through periodic selection, he was able to isolate a gene of interest in his bacteria. He produced a strain of antibiotic-resistant bacteria by exposing his bacterial cultures to antibiotics. He introduced a gene of interest into his bacteria using viruses.

He introduced a gene of interest into his bacteria using viruses.

The current theory is that chloroplasts are descendants of symbiotic cyanobacteria that lived within eukaryotic cells. If we look at their respective genomes, however, we see that the cyanobacteria have many more genes than do chloroplasts. Where did cyanobacteria genes go? None of the answer options is correct. Many of the genes were transported to the nucleus, and others were lost. Nowhere; cyanobacteria and chloroplasts actually have the same number of genes. Endosymbiosis requires a reduction in genetic material in order to be successful. Restriction enzymes removed them.

Many of the genes were transported to the nucleus, and others were lost.

Which of the statements regarding diatoms is false? Diatoms possess mineralized skeletons. Most diatoms are multicellular eukaryotes. Diatoms can produce haploid gametes. Diatoms usually exist in a diploid state. Depending on environmental conditions, diatoms can undergo either meiotic or mitotic cell division.

Most diatoms are multicellular eukaryotes.

_____ results in the oxidation of NH3 to form NO3-, and _____ results in the reduction of NO3- to form N2. Nitrogen fixation; anammox Anammox; nitrogen fixation Denitrification; nitrogen fixation Denitrification; nitrification Nitrification; denitrification Nitrification; nitrogen fixation

Nitrification; denitrification

Why are some single-celled eukaryotes only found as haploid cells for the majority of their lifespan, whereas others are only found as diploid cells for the majority of their lifespan? None of the answer options is correct. Only the eukaryotes that reproduce asexually will occur as haploid cells. Only the eukaryotes that reproduce sexually will occur as diploid cells. Only the eukaryotes that reproduce asexually will occur as diploid cells. Only the eukaryotes that reproduce sexually will occur as haploid cells.

None of the answer options is correct.

Which of the statements are true regarding radiolarians? None of the other answer options is correct. The shells of these organisms are relatively simple and only appear as circles. They possess shells composed of calcium carbonate. The composition of their shells is unique among protists; no other protists possess shells of silica. They likely evolved as a result of high sulfide levels in Earth's oceans.

None of the other answer options is correct.

To which of the superkingdoms does a jellyfish belong? Excavata Stramenopila Opisthokonta Archaeplastida Amoebozoa

Opisthokonta

You have learned that having linear DNA has consequences, the major one being that the DNA is shortened every time it replicates. This does not happen with the circular DNA found in prokaryotes. What, then, is the advantage of having linear DNA? All of these choices are correct. Linear DNA is less susceptible to viruses than circular DNA. Linear DNA is easier to package than circular DNA. Since mitochondria and chloroplasts have circular DNA, nuclear DNA had to be linear. Replication can begin from multiple sites on linear DNA, allowing rapid replication and relieving the evolutionary pressure for a streamlined genome.

Replication can begin from multiple sites on linear DNA, allowing rapid replication and relieving the evolutionary pressure for a streamlined genome.

A researcher is trying to define a bacterial species. How can she accomplish this task? She can identify bacteria with similar plasmid sequences. She can isolate populations of bacteria that have undergone periodic selection. She can identify bacteria with similar sequences for nitrogen-fixation genes. She can evaluate the "interbreeding capacity" between different bacteria.

She can isolate populations of bacteria that have undergone periodic selection.

You may know that scientists are able to synthesize new strands of DNA through a process known as PCR, which utilizes a DNA polymerase derived from bacteria. By repeatedly heating the reaction products to 70˚C, researchers can create new DNA from a template DNA strand. What does this tell you about bacteria compared to archaeons? Some bacteria can survive at higher temperatures compared to archaeons. Bacteria and archaeons can likely both survive at temperatures of 122˚C. Some bacteria can survive at high temperatures, although archaeons can survive in much hotter environments. Archaeons prefer colder environments compared to bacteria.

Some bacteria can survive at high temperatures, although archaeons can survive in much hotter environments.

Which statement is true regarding bacteria? Bacteria can influence and alter the behavior of eukaryotes. The majority of bacteria species have already been cultured. Like many eukaryotes, bacteria species can be described by the biological species concept. Many groups of bacteria include methanogenic organisms. Soil "genome surveys" cannot be used to identify new bacteria species

bacteria can influence and alter the behavior of eukaryotes

The _____ bacterial group contains organisms that normally inhabit the intestinal tracts of humans (depending on their diet) and can additionally break down cellulose Proteobacteria Bacteroidetes Firmicutes Gram-positive Heliobacteria

bacteriodetes

Which of the answer choices are "usable" forms of nitrogen (N) and sulfur (S) that plants and animals can assimilate to build proteins? both N2 and S2 both S2 and S3 both NH3 and S2 both SO4 and NO3 both N2 and NO3

both SO4 and NO3

The last common ancestor of fungi, mammals, and archaeons likely had which characteristics? both a distinct nucleus and a plasma membrane both membrane-bound organelles and a circular chromosome both a circular chromosome and membrane-bound organelles both free-floating genetic material (DNA) and a distinct nucleus both a plasma membrane and a circular chromosome

both a plasma membrane and a circular chromosome

Nitrogen gas (N2) in the atmosphere can be directly utilized by which organisms? bacteria algae both bacteria and archaeons archaeons eukaryotes

both bacteria and archaeons

A woman decides to become a vegan and suddenly cuts out all animal products from her diet. She also makes the decision to no longer eat sugar. This will result in: both more bacteroidetes and fewer firmicutes being present in her intestines. more firmicutes being present in her intestines. fewer bacteroidetes being present in her intestines. no change in the composition of her intestinal bacteria. both more firmicutes and fewer bacteroidetes being present in her intestines.

both more bacteroidetes and fewer firmicutes being present in her intestines.

A doctor wants to determine the origin of the bacteria in the intestinal tract of one of her patients. How can she do this? examining the bacteria present in the eggs of the patient's mother All of these choices are correct. by examining the bacteria present in the sperm of the patient's father by determining the bacteria present in the food the patient eats

by determining the bacteria present in the food the patient eats

Which of the answer choices is a similarity between Bacteria and Archaea? histones incorporated into chromosomes ability to produce methane metabolically capable of chemoautotrophy ester linkages in membrane lipids

capable of chemoautotrophy

A researcher discovers a new prokaryote that lives on the seafloor near hydrothermal vents. This organism reduces CO2 to form C6H12O6 and also derives energy from H2 (by oxidation). This prokaryote is a: chemoautotroph. chemoheterotroph. photoautotroph. photoheterotroph.

chemautotroph

If biologists could quantify all the bacterial and human cells within the human body, they would find that there are far more human cells. true false

false

If photosynthesis was mapped on a prokaryotic phylogenetic tree, all photosynthetic groups would have a single common ancestor. true false

false

Nitrification, or the oxidation of ammonia to nitrate (NO3-), is a strictly anaerobic process. true false

false

Not all eukaryotes contain a dynamic cytoskeleton or even any cytoskeleton. The smallest eukaryotes actually possess rigid cell walls composed of peptidoglycan, much like bacteria. true false

false

The terms algae and protozoa have significant phylogenetic meaning. true false

false

Which of the groups has well-developed vascular tissues? liverworts and hornworts ferns hornworts mosses liverworts

ferns

Given the presence of Faecalibacterium in the gastrointestinal tracts of Europeans, these bacteria are likely: Acidobacteria. Tenericutes. Proteobacteria. Firmicutes. Bacteroidetes.

firmicutes

Eukaryotes have more ways to obtain energy than prokaryotes. true false

false

Which of the statements is a hypothesis to explain the origin of the modern eukaryotic cell? None of the answer options is correct. A cyanobacterial cell became incorporated into an archaeon at the same time that eukaryotes developed. A cell evolved a nucleus first, then incorporated a cyanobacterial cell that became a lysosome. A cell evolved a nucleus first, then incorporated a cyanobacterial cell that became a mitochondrion. A cell evolved a nucleus first, then incorporated a proteobacterial cell that became a mitochondrion

A cell evolved a nucleus first, then incorporated a proteobacterial cell that became a mitochondrion.

A researcher is studying a specific strain of bacteria. In one of her cultures, she notices that the bacteria are antibiotic-resistant. As there are no genes in the chromosome that could confer antibiotic-resistance in these bacteria, the researcher assumes this is the result of a spontaneous mutation. What is another possible explanation? A gene conferring antibiotic resistance is present on mitochondria. A gene conferring antibiotic resistance is present on ribosomes. A gene conferring antibiotic resistance is present on peptidoglycans. A gene conferring antibiotic resistance is present on plasmids.

A gene conferring antibiotic resistance is present on plasmids.

Imagine that a researcher discovers a new type of organelle in single-celled eukaryotes. She suspects that this new organelle is the result of endosymbiosis. How could she support this theory? She could use electron microscopy to determine if any structural similarities exist between this new organelle and prokaryotic cells (such as whether it is similar to proteobacteria or cyanobacteria). She could determine whether this organelle has both an inner and outer membrane. If this organelle has its own DNA, she could compare its genetic sequence to those of certain prokaryotes. All of these answer options represent ways to test this theory

All of these answer options represent ways to test this theory.

As diffusion plays a large role in determining the size of bacterial cells, bacteria are often shaped like which of the answer choices? spirals filaments rods All of these choices are correct. spheres

All of these choices are correct.

Which of the features is responsible for the evolutionary success of eukaryotes? All of these choices are correct. localizing where energy metabolism takes place possessing a dynamic endomembrane system possessing a dynamic cytoskeleton having complex patterns of gene regulation

All of these choices are correct.

Imagine that aliens are attempting to grow humans in sterile chambers. Much to the aliens' disappointment, these humans are sickly, despite the fact that they have no bacteria in their gastrointestinal tracts. What could these experiments tell you about how bacteria populate the human gut? All of these choices are correct. Bacteria are present in the amniotic fluid and could enter the human stomach during development or shortly after birth. Bacteria are present in human sperm and eggs and appear in the human stomach as soon as it develops. Bacteria are present in the environment and populate the human stomach throughout the course of an individual's life. Bacteria are present in the amniotic fluid and could enter the human stomach during development or shortly after birth; bacteria are present in the environment and populate the human stomach throughout the course of an individual's life.

Bacteria are present in the amniotic fluid and could enter the human stomach during development or shortly after birth; bacteria are present in the environment and populate the human stomach throughout the course of an individual's life.

Imagine that a scientist is able to reverse the principles of diffusion such that molecules preferentially move from regions of low concentrations to regions of high concentrations. How would this affect the morphology of bacteria? Bacteria would have to prevent the diffusion of molecules out of the cell, potentially allowing for bacteria to grow wider. This change would not likely affect bacteria morphology, as diffusion plays no role in determining bacteria shapes. Bacteria would have to actively transport molecules across the cell membrane, potentially allowing for bacteria to grow larger, and prevent the diffusion of molecules out of the cell, potentially allowing for bacteria to grow wider. Bacteria would have to actively transport molecules across the cell membrane, potentially allowing for bacteria to grow larger.

Bacteria would have to actively transport molecules across the cell membrane, potentially allowing for bacteria to grow larger, and prevent the diffusion of molecules out of the cell, potentially allowing for bacteria to grow wider.

A student notices two bacteria cells of the same species in close association with one another, with a thin projection running between them. He assumes that these two cells are fusing, forming a new individual. His instructor informs him that this is not the case. Why? Cell fusion does not occur with bacterial cells, and these cells are likely undergoing conjugation. These cells are likely undergoing transformation. Cell fusion does not occur with bacterial cells. These cells are actually daughter cells resulting from meiosis. Cell fusion does not occur with bacterial cells, and these cells are likely undergoing transformation.

Cell fusion does not occur with bacterial cells, and these cells are likely undergoing conjugation.

It appears that eukaryotic diversity took off around 800 million years ago. What is the best explanation for this? Chloroplasts first evolved 800 million years ago. All of these choices are correct. The ability to prey on other protists originated or expanded 800 million years ago, setting in place an evolutionary arms race. By 800 million years ago, enough time had passed since the arrival of eukaryotes for evolutionary adaptation to take place. Eukaryotic organisms first arrived 800 million years ago, and when they did, they quickly diversified.

The ability to prey on other protists originated or expanded 800 million years ago, setting in place an evolutionary arms race

A doctor is treating a patient for an apparent bacterial infection. She prescribes antibiotics that target either the peptidoglycan in bacterial cell walls or the bacterial translational machinery. To her surprise, this treatment does not work. Why might this treatment be ineffective? The bacterium may have developed resistance to these treatments. All of these choices are correct. The patient may be infected with bacteria that have cell walls composed of cellulose. The patient may be infected with bacteria that have cell walls composed of chitin.

The bacterium may have developed resistance to these treatments

Most eukaryotic cells contain mitochondria, but a few single-celled eukaryotic organisms found in oxygen-free environments do not. Which of the observations led biologists to reject the hypothesis that these mitochondria-free eukaryotes evolved before the endosymbiotic event that established mitochondria in other eukaryotes? The nuclear genome of these mitochondria-free eukaryotes contains relics of mitochondrial genes. Some eukaryotes have chloroplasts instead of mitochondria. All eukaryotes have remnant chloroplast genes. All eukaryotes exhibit some sort of energy utilization.

The nuclear genome of these mitochondria-free eukaryotes contains relics of mitochondrial genes

A researcher is comparing the sequences of genes encoding cell wall proteins in archaeons with those coding cell wall proteins in bacteria. How similar do you expect these sequences will be? These sequences will be dissimilar, as archaeon cell walls are not composed of peptidoglycan. These sequences will be dissimilar, as archaeons have chitin-based cell walls and bacteria primarily have peptidoglycan-based cell walls. These sequences will be similar, as bacteria and archaeons belong to the same prokaryotic domain. These sequences will be similar, as both archaeons and bacteria have cell walls composed of peptidoglycan variants.

These sequences will be dissimilar, as archaeon cell walls are not composed of peptidoglycan.

Why may young leaves that are just emerging from the bud be considered sinks for phloem transport? They produce carbohydrates through photosynthesis. Their sucrose concentration is too high. They do not have developed sieve tubes. They consume more carbohydrates than they produce.

They consume more carbohydrates than they produce.

What benefit do mycorrhizal fungi receive in their symbiotic relationship with plants? They get increased phosphate availability. They receive carbohydrates. They get genetic information. They are protected from predation. They consume plant cells.

They receive carbohydrates.

A researcher discovers a new microfossil. At first, he is uncertain whether he has found a fossilized bacterium, archaeon, or protist. After careful study, he determines that it is a fossilized protist. What features were present in this microfossil that led the researcher to this conclusion? All of these choices are correct. This microfossil contained morphologically complex cell walls. The microfossil contained evidence of mitochondria, chloroplasts, or both. DNA survived in this microfossil over the millennia; the DNA sequence of the microfossil was likely similar to those present in certain modern-day protists. This microfossil was of an organism that had a distinct endomembrane system (that is, it had a nuclear membrane, an endoplasmic reticulum, and so forth).

This microfossil contained morphologically complex cell walls.

Which of the statements accounts for why eukaryotic cells are typically much larger than prokaryotic cells? Using molecular motors, eukaryotic cells can transport materials throughout their cytoplasm much faster than prokaryotic cells can; prokaryotic cells have to rely on simple diffusion. None of the answer options is correct. Reproducing sexually requires the cells to be larger so that everything in the cell can be evenly distributed to the daughter cells. A eukaryotic nucleus is so large that the cell has to be bigger to allow space for other organelles. Because eukaryotic cells have more DNA, their cell volume has to be larger.

Using molecular motors, eukaryotic cells can transport materials throughout their cytoplasm much faster than prokaryotic cells can; prokaryotic cells have to rely on simple diffusion.

How does current theory explain the origin of a nucleus in eukaryotic cells? A prokaryotic cell was engulfed by another cell and became specialized in DNA transcription. None of the other answer options is correct. While there are some competing theories on the origin of the nucleus, neither theory discussed in the text really explains the origin of the nucleus. A prokaryotic cell was engulfed by another cell and became specialized in DNA replication. A prokaryotic cell was engulfed by another cell and became specialized in translation.

While there are some competing theories on the origin of the nucleus, neither theory discussed in the text really explains the origin of the nucleus.

Chloroplasts are thought to have originated from a symbiotic relationship between an ancient eukaryotic cell and: algae. an archaeal cell. a cyanobacterium. a proteobacterium.

a cyanobacterium

What structure is found in all members of the superkingdom Stramenopila? a chloroplast a second, smooth flagellum None of the other answer options is correct. a flagellum with stiff hairs a cell wall

a flagellum with stiff hairs

Which of the answer choices is the best description of a protozoan? a photosynthetic protist a chemotrophic protist a heterotrophic protist a heterotrophic prokaryote a chemotrophic prokaryote

a heterotrophic protist

Which of the answer choices is the best description of algae? a heterotrophic protist a photosynthetic protist a chemotrophic prokaryote a heterotrophic prokaryote a chemotrophic protist

a photosynthetic protist

Oxygen is used during a reaction if the process is: oxygenic. aerobic. anoxygenic. anaerobic

aerobic

Photosynthetic protists are informally referred to as: fungi. algae. protozoa. plants.

algae

A young paleontologist is extremely excited. In sedimentary rocks dating from 70 million years ago, she has found some new microfossils. The shells of which organisms likely contributed to the accumulation of sediments on the seafloor (and the formation of these sedimentary rocks)? diatoms radiolarians coccolithophorids foraminiferans All of these choices are correct.

all of these choices are correct

Which superkingdom contains members that are responsible for forming red tides? Excavata Alveolata Amoebozoa Archaeplastida Stramenopila

alveolata

To which of the superkingdoms do slime molds belong? Opisthokonta Archaeplastida Stramenopila Amoebozoa Excavata

amoebozoa

You are in a lab studying a newly discovered cell type. You observe a rigid cytoskeleton in this cell, along with a nucleus and a compartmentalized interior. How would you classify this cell? as an advanced prokaryotic cell, because it has a rigid cytoskeleton None of the answer options is correct. as a primitive prokaryotic cell as a eukaryotic cell that has to be heterotrophic as a possible transitional cell changing from prokaryotic to eukaryotic

as a possible transitional cell changing from prokaryotic to eukaryotic

When reduction of SO4 to form H2S occurs during _____, SO4 _____ electrons. assimilation; loses anaerobic respiration; gains anaerobic respiration; loses assimilation; gains anammox; loses anammox; gains

assimilation; gains

If all eukaryotes suddenly died off, the Earth's carbon cycle would immediately collapse and cease to exist. true false

false

Because thaumarchaeote archaeons reduce CO2 in their environments to produce organic compounds and also oxidize inorganic substances to gain energy, they are: chemoheterotrophs. photoheterotrophs. chemoautotrophs. photoautotrophs

chemoautotrophs

Photorespiration _____ O2 and _____ CO2. releases; releases consumes; releases consumes; consumes releases; consumes

consumes; releases

effectively limits the size a bacterium can reach. The bigger the bacterial cell, the slower the rate of movement of nutrients from the edge of a bacterium to its interior Diffusion Differentiation Transduction Conjugation

diffusion

Sexual fusion brings two haploid cells together to produce a _____ cell. haploid None of the other answer options is correct. diploid polyploid

diploid

All bacteria are unicellular. true false

false

As part of aerobic respiration, O2 is reduced and loses electrons, and glucose (C6H12O6) is oxidized and gains electrons true false

false

Chloroplasts originated from endosymbiotic cyanobacteria once and only once. true false

false

In which group of Archaeplastids are the chloroplasts most similar to those of the ancestral cyanobacterial endosymbiont? streptophyte algae glaucocystophytes red algae green algae viridoplantae

glaucocystophytes

In the early 20th century, an experiment was conducted to determine how large the forces are that allow leaves to pull water from the soil. The rate at which water flowed from a reservoir into the cut tip of an actively transpiring plant was _____ the flow rate through the branch tip when it was subsequently attached to a vacuum pump equal to greater than less than

greater than

In eukaryotes that lack mitochondria, what structures are present to generate ATP for cellular use? chloroplasts or hydrogenosomes chloroplasts hydrogenosomes There are no structures that generate ATP in eukaryotes that lack mitochondria. There are no eukaryotes that lack mitochondria.

hydrogenosomes

Where is carbon stored in a CAM plant prior to its assimilation into sugars? in the air spaces between cells in stomata in epidermal cells in the vacuole in mesophyll cells

in the vacuole

When the forces pulling water through the xylem are large, the risk of vessel collapse is _____, and the chance that an air bubble will spread from one vessel to another is _____. increased; decreased increased; increased decreased; decreased decreased; increased

increased; increased

Green algae are most closely related to: diatoms. brown algae. land plants. red algae.

land plants.

Which of the substances helps make xylem cells very rigid to avoid collapse? parenchyma spongin lignin chitin cellulose

lignin

_____ is an element that is abundant in Earth's atmosphere; however, usable forms of this element, such as ammonia, are comparatively rare in certain soils. Symbiotic relationships between plants like soybeans and bacteria have formed to circumvent this problem. Sulfur Carbon Oxygen Nitrogen

nitrogen

During _____, N2 from the atmosphere is converted to NH3. Primary producers can then use the nitrogen from NH3 to build organic compounds denitrification anammox assimilation nitrogen fixation

nitrogen fixation

A researcher is culturing several different strains of bacteria in the same petri dish. One day, he finds that all of the strains have died off except one. He continues to grow his bacteria for several weeks, and new strains develop. However, after a month he again notices that all but one of his bacterial strains have died off. This is an example of: acyclic selection. continuous selection. periodic selection. nonperiodic selection. artificial selection.

periodic selection

Photorespiration: drives photosynthesis. is a process similar to cellular respiration, producing energy for plants. results when rubisco binds O2. generates ATP. occurs in equal parts with photosynthesis.

results when rubisco binds O2.

The contents of the xylem sap in plant roots are: very acidic. always high in sugars. selectively maintained by endodermal cells. always higher in water than the surrounding soil. the same as the solute composition of the surrounding soil.

selectively maintained by endodermal cells.

Xylem sap and soil water differ in _____ because of _____. solute composition; selective uptake by the endodermis solute composition; selective uptake by the epidermis pH; H+ exclusion by the endodermis solute composition; selective uptake by mycorrhizae

solute composition; selective uptake by the endodermis

Imagine that your uncle is a scientist who has found himself in possession of a time machine. The two of you travel back to the Paleozoic Era and are perusing the oceans for microscopic life. What will you find? only organisms reminiscent of red algae some photosynthetic organisms (cyanobacteria and green algae) and radiolarians and other heterotrophic protists an array of photosynthetic organisms, including cyanobacteria, dinoflagellates, and diatoms some photosynthetic organisms, but these would be limited to cyanobacteria and algae radiolarians and other organisms with either silica or calcium-carbonate shells

some photosynthetic organisms (cyanobacteria and green algae) and radiolarians and other heterotrophic protists

Vascular plants store most carbohydrate reserves as: starch. lipids. glycogen. sucrose. glucose.

starch

To which of the superkingdoms do diatoms belong? Excavata Archaeplastida Amoebozoa Stramenopila Opisthokonta

stramenopila

The forces that result in bulk flow of phloem sap originate when _____ is actively pumped into the phloem from _____ cells in the leaf, which causes _____ to enter via _____. sugar; epidermal; water; active transport water; epidermal; sugar; active transport sugar; mesophyll; water; osmosis water; mesophyll; sugar; osmosis

sugar; mesophyll; water; osmosis

Organelles have their own genomes. When chloroplast DNA is sequenced and compared to genomes from members of the cyanobacteria, the chloroplast DNA sequence is nested within the genomes of cyanobacteria. This is strong evidence for the hypothesis that: cyanobacteria are so diverse that any organelle genome would nest within the group. photosynthesis evolved only once on the eukaryotic tree. cyanobacteria are descended from chloroplasts. the chloroplast originated as a symbiotic cyanobacterium that became permanently incorporated into its host.

the chloroplast originated as a symbiotic cyanobacterium that became permanently incorporated into its host.

In vascular plants, water transport works only if: the water column is continuous between leaves and soil. the xylem has access to a constant source of ATP. xylem and phloem are in close proximity. roots are able to generate turgor pressure.

the water column is continuous between leaves and soil.

Which statement is true regarding archaeons? Like bacteria, they are killed by peptidoglycan-targeting antibiotics. They have cell walls composed of chitin. Their transcriptional machinery is similar to the machinery used by eukaryotes. They do not include organisms that can undergo methanogenesis. Unlike bacteria, their cell size and cell shape are not determined by diffusion.

their transcriptional machinery is similar to the machinery used by eukaryotes

Recall that Archaea and Bacteria used to be grouped in the same category. How were archaeons first distinguished from other prokaryotes? through differences in ribosomal RNA sequences through the fact that archaeons have linear and not circular chromosomes through the observation that archaea cell size is independent of diffusion through the lack of horizontal gene transfer in archaeons through differences in cell size and shape

through differences in ribosomal RNA sequences

Plants require the most water _____, but water is also critical _____. as an input to photosynthesis reactions; to keep cells fully hydrated to replace the water vapor lost to transpiration; as an input to photosynthesis reactions for reproduction and spore dispersal; as an input to photosynthesis reactions as an input to photosynthesis reactions; to replace the water vapor lost to transpiration

to replace the water vapor lost to transpiration; as an input to photosynthesis reactions

Based on the characteristics of crenarchaeote (included in TACK) archaeons and euryarchaeote archaeons, these organisms likely first evolved in oxygen-poor habitats true false

true

Choanoflagellates are the closest protistan relatives of animals. true false

true

Many plants and animals can reproduce asexually. true false

true

Phylogenies can be generated from molecular sequence data derived either from single genes or from entire genomes true false

true

Protist diversification may be linked to changes in interactions with other contemporary protists, as some protists began to consume other protists and not just bacteria or archaeons. true false

true

Selection favors prokaryotic organisms that maintain smaller genomes over prokaryotic organisms with larger genomes. true false

true

The genes in chloroplasts more closely match the genes found in cyanobacteria as compared to the genes found in the nuclei of photosynthetic eukaryotes. true false

true

The photosynthetic amoeba Paulinella is an example of a second chloroplast endosymbiotic event involving a cyanobacterium. true false

true

The term coenocytic refers to a giant cell containing many nuclei. true false

true

There is no known symbiosis between a heterotrophic host and a photosynthetic partner in mammals. true false

true

Which of the factors causes stomata to close? sunlight water loss high leaf temperature low CO2 in the leaf

water loss

Under what circumstances can leaves be sinks for carbohydrates delivered by phloem? when they are very young when they are very old when the roots contain more carbohydrates than they need when there are no reproductive organs that have first priority for carbohydrates

when they are very young