God help me

What is the difference between an F⁺ donor and an Hfr donor?

The Hfr donor has an F factor integrated into its main chromosome, but the F⁺ donor does not.

What usually happens to the recipient cell following conjugation with an Hfr cell?

The recipient cell remains an F^- cell.

Which of the following typically produces a recombinant F⁺ recipient cell?

conjugation between an F⁺ cell and an F^- cell

Which of the following could cause DNA from the main chromosome of a donor cell to be incorporated into the main chromosome of the recipient cell?

conjugation between an Hfr cell and an F^- cell

Conjugation between an Hfr cell and an F^- cell may result in DNA being transferred from the main chromosome of the donor cell to the main chromosome of the recipient cell. This occurs when the Hfr cell transfers a piece of DNA to the recipient cell and then crossing over occurs between the transferred piece of DNA and the recipient cell's chromosome.

Suppose conjugation occurs between an Hfr cell and an F^- cell. Although not typical, what would have to occur for the recipient cell to become an Hfr cell?

The entire F factor would have to be incorporated into the recipient cell’s chromosome.

What are the characteristics of a gram positive bacteria?

• Thick Peptidoglycan layer

• Appear purple after gram staining

• Alcohol rinse does not remove crystal violet

What are the characteristics of a gram-negative bacteria?

• Thin peptidoglycan layer

• Appear pink after staining

• Alcohol rinse easily removes crystal violet

• An outer membrane that consists of lipopolysaccharides

What do both gram positive and gram negative bacteria have?

They both have a plasma membrane

Azotobacter is a genus of bacteria that live in soil and have the following characteristics:

• They use O₂ for cellular respiration

• They have a relatively thin layer of peptidoglycan in their cell wall

• They can convert atmospheric nitrogen to ammonia.

• They are shaped like rods.

Azotobacter is a genus of rod-shaped bacteria (bacilli). After Gram staining, bacteria in this genus appear pink due to the thin peptidoglycan layer in their cell wall. They require oxygen for cellular respiration and can convert atmospheric nitrogen to ammonia, which they incorporate into amino acids and other organic molecules

What is conjugation

• Involves the transfer of DNA from an Hfr cell to an F- cell

• requires cell to cell contact

What is transduction?

involves bacteriophage transferring pieces of bacterial DNA from one cell to another

What is transformation?

involves DNA from the environment being taken up into a bacterial cell

What do all three genetic transfers in bacteria do?

They involve recombination

Antibiotic-resistant bacteria are becoming an increasing problem. Some bacteria that were once killed by common antibiotics have acquired the ability to survive in the presence of those antibiotics. How can bacteria acquire antibiotic resistance?

Bacteria can acquire random mutations that allow them to grow in the presence of antibiotics.

Bacteria can gain an antibiotic-resistance gene by conjugating with another species of bacteria.

Bacteria can pick up an antibiotic-resistance gene from the environment through transformation.

Bacteria can acquire antibiotic-resistance genes by becoming infected with a virus that contains an antibiotic-resistance gene.

Which of the following is true of generalized bacteriophage transduction?

The bacteriophage packages fragments of bacterial DNA into new phage particles.

1. Binary fission is a form of ______ because a single individual is the sole parent and passes copies of all its genes to its offspring

asexual reproduction

During binary fission, DNA replication begins at the ______ and continues all the way around the circular chromosome.

origin of replication

3. When DNA replication is complete and the bacterium has reached twice its original size, the ______ grows inward, dividing the parent cell into two daughter cells.

plasma membrane

In theory, the two daughter cells are _______ each other and the parent cell.

genetically identical to

However, mistakes made during DNA replication sometimes result in ____, changes to the nucleotide sequence of DNA.

mutations,

The rapid reproduction and large population sizes of many bacterial populations mean that even a small mutation rate can lead to considerable _______

genetic variation.

The F + cell can

• donate a plasmid to another cell

• carries the F factor in a plasmid

The HFR cell can

• May donate genes from its chromosome to another cell

• carries the f factor in its circular chromosome

The F- cell can

• may become F + after conjugation with an F + cell

• may become recombinant after conjugation with an HFR cell

• May receive genetic material but can not give genetic material

Which of the following features occurs in prokaryotic and in some eukaryotic cells?

a cell wall

What is the function of fimbriae?

they are used to attach the cell to its substrate or to other prokaryotes

The predatory bacterium Bdellovibrio bacteriovorus is able to penetrate a gram-negative bacterium that has a slimy cell covering. What is the correct sequence of structures penetrated by B. bacteriovorus on its way to the prey's cytoplasm

capsule, lipopolysaccharide membrane, peptidoglycan, phospholipid membrane

A bacterium has the following characteristics:
· It adheres to the human intestinal lining using a feature that protects it from phagocytes, bacteriophages, and dehydration.
· It can survive being boiled.
· It contains no plasmids and relatively little peptidoglycan.

Which of the following characteristics allows this bacterium to survive in a human who is taking penicillin pills?

gram-negative cell wall

A bacterium has the following characteristics:
· It adheres to the human intestinal lining using a feature that protects it from phagocytes, bacteriophages, and dehydration
· It can survive being boiled
· It contains no plasmids and relatively little peptidoglycan

Which of the following characteristics allows this bacterium to adhere to the intestinal lining?

fimbriae

A bacterium has the following characteristics:
· It adheres to the human intestinal lining using a feature that protects it from phagocytes, bacteriophages, and dehydration
· It can survive being boiled
· It contains no plasmids and relatively little peptidoglycan

Which of the following statements best describe the cell wall of this bacterium?

It has an outer membrane of lipopolysaccharide.

In which part of a bacterium is the complete chromosome found?

nucleoid

Which of the following statements about flagella provides the best support for the claim that the flagella from eukaryotes and bacteria evolved independently?

The protein structure and the mechanism of movement in eukaryotes flagella are different from those of bacteria flagella.

Some bacteria possess antibiotic resistance, as well as the ability to survive through adverse conditions. Where in this type of bacteria is the DNA located?

plasmids, nucleoid, and endospore

Chloramphenicol is an antibiotic that targets prokaryotic ribosomes, but not eukaryotic ribosomes. Based on an understanding of eukaryotic origins, which of these questions might be a target for research on chloramphenicol from this observation?

If chloramphenicol inhibits prokaryotic ribosomes, should it not also inhibit mitochondrial ribosomes?

Select the valid comparison between eukaryotes and prokaryotes.

Prokaryote cells have simpler internal structure and genomic organization than eukaryotic cells.

Identify the thylakoid membrane of the cyanobacterium shown here.

The thylakoid membrane of the cyanobacterium is an infolded plasma membrane.

Which of the following statements correctly answers how the large amount of genetic variation observed in prokaryotes arises?

They have extremely short generation times and large populations.

They can exchange DNA with many types of prokaryotes by way of horizontal gene transfer.

Genes for the resistance of antibiotics are often located __________.

on plasmids

A process that cannot produce genetic variation in bacterial populations is

meiosis.

Which of the following structures is most likely missing in a bacterium that regenerates from an endospore lacking any of the plasmids from the original cell?

antibiotic-resistant genes

Which of the following statements correctly describes F^- cells and F⁺ cells?

F⁺ cells function as DNA donors during conjugation and F^- cells function as DNA recipients during conjugation

A bacterium has the following characteristics:
· It adheres to the human intestinal lining using a feature that protects it from phagocytes, bacteriophages, and dehydration.
· It can survive being boiled.
· It contains no plasmids and relatively little peptidoglycan.
· The bacterium is not susceptible to the penicillin family of antibiotics.
· The cell also lacks F factors and F plasmids.

Which of the following statements about the bacteria is most probably accurate?

The bacterium is unable donate DNA through conjugation with another cell.

Which of the following statements is the most likely result of conjugation involving a bacterium that contains a copy of a plasmid containing a gene for tetracycline resistance with one that does not?

the rapid spread of tetracycline resistance to other bacteria in the population

Which of the following processes leads to genetic recombination by the introduction of viral DNA into a bacterium?

transduction

Which of the following processes contributes to genetic recombination in prokaryotes?

Transduction

Bacteria that live around deep-sea, hot-water vents obtain energy by oxidizing inorganic hydrogen sulfide belched out by the vents. They use this energy to build organic molecules from carbon obtained from the carbon dioxide in seawater. These bacteria are __________.

chemoautotrophs

Which of the following statements about obligate anaerobes is correct?

They are poisoned by O₂.

Photoautotrophs use

light as an energy source and CO2CO2 as a carbon source.

What are prokaryotes?

Are single celled organisms make up the Bacteria and Archaea domains

• Contains no membrane - bound organelles (no nucleus, no gogli apparatus, etc etc)

• Has ribosomes

• DNA is located in the cytoplasm in a region called the nucleoid

• Some have flagella for movement

What are the 3 domains?

1) Bacteria

2) Archaea

3) Eukarya

What are beneficial adaptations of prokaryotes?

• short mitosis time, large population

• mutations produce genetic diversity for evolution and adaptation

• bacterial cells evolve and become diverse metabolically and structurally to endure environmental conditions.

Who were the first to inhibit the earth?

prokaryotes

Which of the following statements is true of secondary endosymbiosis?

An organism containing an endosymbiont is engulfed by another organism and becomes an endosymbiont.

Plastids that are surrounded by more than two membranes are evidence of

secondary endosymbiosis.

According to the endosymbiotic theory, it was adaptive for the larger host cell to keep the engulfed cell alive, rather than digesting it as food because ________

the engulfed cell provided the host cell with adenosine triphosphate (ATP)

Biologists think that endosymbiosis gave rise to mitochondria before plastids partly because ______

all eukaryotes have mitochondria (or their remnants), whereas many eukaryotes do not have plastids.

The chloroplasts of land plants are thought to have been derived according to which evolutionary sequence?

cyanobacteria →→ green algae →→ land plants

Which of the following characteristics is common among all protists?

eukaryotic

An individual mixotroph loses its plastids, yet continues to survive. Which of the following statements best explains this organism's continued survival?

It engulfs organic material by phagocytosis or by absorption.

Which of the following protists have chloroplasts (or structures since evolved from chloroplasts) thought to be derived from ancestral green algae?

chlorarachniophytes

Which of the following structures in chlorarachniophytes provides evidence that they evolved through the endosymbiosis of a green alga by a heterotrophic eukaryote?

nucleomorph

Use the following information to answer the question.

Giardia intestinalis is an intestinal parasite of humans and other mammals that causes intestinal ailments in most people who ingest the cysts. The cysts are dormant forms of this protist that are expelled in the feces of organisms that ingest them.

Which of the following structures to the cysts of Giardia function most like?

endospores of bacteria

Which of the features below are found in all protist lineages?

Mitochondria

Which of the following statements supports the hypothesis of an endosymbiotic origin of mitochondria?

The fact that mitochondria have their own DNA provides strong support for the hypothesis of an endosymbiotic origin of mitochondria.

Which of the following are two groups that are adapted to anaerobic conditions and contain modified mitochondria that lack DNA?

diplomonads and parabasalids

Which supergroup is currently the most controversial in terms of the hypothesis for its origin?

the excavates

Consider the following data:
· Most ancient eukaryotes are unicellular.
· All eukaryotes alive today have a nucleus and cytoskeleton.
· Most ancient eukaryotes lack a cell wall.

Which of the following conclusions about the first eukaryotes is most consistent with the data presented?

They were capable of phagocytosis.

Which of the following statements compares the mitosomes of diplomonads and mitochondria of other types of eukaryotes?

Mitosomes in diplomonads lack a functional electron transport chain and other eukaryotes possess one.

If the mitosomes of Giardia contain no DNA, yet are descendants of what were once free-living organisms, then where are we likely to find the genes that encode their structures?

nucleus

Many parasitic members of the excavates lack plastids and have highly reduced mitochondria. Which of the following statements explains these observations?

These parasites typically live in low-oxygen conditions and therefore loss of genes for plastids and mitochondria did not result in lower fitness.

Which of the following statements correctly compares prokaryotic and eukaryotic flagella?

They have different structures.

Which of the following mitigation strategies would be most likely to cause evolution of a drug-resistant strain of Plasmodium?

widespread, frequent use of a single drug in patients suffering from malaria

Part complete

What advantage do organisms that reproduce sexually have over organisms that reproduce asexually?  

Their offspring may be more adaptable to changes in the environment.  

Which term describes the fusion of two gametes to form a diploid zygote?    

Fertilization

Which term describes the multicellular haploid form of a protist that shows alternation of generations?  

Gametophyte  

Which structure mediates the attachment of spores to a surface on which to grow?

Holdfast    

Which of the following statements about Ulva's haploid stage is true?

Haploid cells are produced by meiosis of diploid cells

How does the haploid form of Ulva "switch" to its diploid form?    

Gametophytes produce cells that undergo mitosis to produce gametes that fuse to form a zygote.

True or false? Organisms that exhibit alternation of generations reproduce sexually in the diploid stage.    

false

Plasmodium exhibits consumption in its interactions with mosquitoes and humans. Which process is not an example of consumption?

Commensalism.

Which form of Plasmodium is the immediate cause of anemia in humans?

Merozoites.

Which of the following statements about the Plasmodium parasite is true?

Merozoites live off the hemoglobin and nutrients in red blood cells and divide to produce more merozoites, destroying red blood cells in the process.

How do humans combat infection by the Plasmodium parasite?

Cytotoxic T cells destroy infected liver cells by recognizing a Plasmodium protein bound to an HLA protein on the surface of those cells.

The video describes a coevolutionary arms race between the Plasmodium parasite and its human hosts.

True or false? One example of a coevolutionary arms race is when faster deer evolve and favor wolves and cougars that have stronger eyesight and senses of smell.

True

A sign on the beach states,"Beach Closed, Red Tide". The organisms interfering with your use of this beach are probably __________.

dinoflagellates

When a mosquito infected with Plasmodium first bites a human, what is the first process carried out by the Plasmodium?

the cells infect the human liver cells

Which of the following pairs of protists and their ecological roles are correctly matched?

apicomplexans–parasites of animals

Which of the following characteristics do dinoflagellates exhibit?

They possess two flagella.

You are given an unknown organism to identify. It is unicellular and heterotrophic. It is motile, using many short extensions of the cytoplasm, each featuring the 9 + 2 filament pattern. It has well-developed organelles and two nuclei, one large and one small. To which of the following groups does this organism likely belong?

ciliate

Which of the following is a characteristic commonly found in ciliates?

They are often multinucleate.

Reinforced, threadlike pseudopods that can perform phagocytosis are generally characteristic of which of the following groups or organisms?

foramifera

A porous test (shell) of calcium carbonate, through which pseudopodia protrude, is characteristic of which of the following groups of organisms?

foraminiferans

You have discovered a new species aquatic protist that is a primary producer. It cannot swim on its own. It appears to be resistant to physical damage from wave action due to the presence of a glass-like wall. Which of the following organisms would this organism be most like?

diatom

A seaweed that grows in shallow, cold water and undergoes heteromorphic alternation of generations is most probably what type of alga?

brown

Which of the following structures provides motility in species of paramecium?

many cilia

Ciliates like Paramecium typically reproduce asexually. Which process in Paramecium results in genetic recombination but no increase in population size?

conjugation

Paulinella chromatophora is a cercozoan that secretes a test, or case around itself consisting of plates made of silica. Which of the following is a rhizarian that would be in competition with P. chromatophora for the silica needed to make these plates, assuming limited quantities of silica in the environment?

radiolarians

Which group of organisms (ciliates, animals, or plants) has the most complex cells?

Ciliates

Archaeplastids, which include land plants and red and green algae, are thought to have descended from a heterotrophic protist that engulfed a(n) __________.

cyanobacterium

Which group is correctly paired with its description?

diplomonads−−protists with modified mitochondria