Mastering Unit 2 Review

The basal body is comprised of which structural component(s) of flagella? a. Filament b. Rod and Rings c. Rod and Hook d. Rod e. Rings f. Hook

b. Rod and Rings

Why is ATP required for glycolysis?

ATP makes it easier to break apart glucose into two three-carbon molecules.

What is the intermediate product formed by pyruvic acid during alcoholic fermentation?

Acetaldehyde

Where would you expect to find electron transport chains in a prokaryote?

Along the plasma membrane

What is the function of GTP?

An energy carrier

Why are receptors on the cell surface necessary for bacterial movement? a. The receptors actually spin the flagella. b. The receptors sense the stimulus and send signals to the flagella. c. The bacterium contains receptors that are sensitive to light. d. The receptors physically alter shape to steer the bacterium.

b. The receptors sense the stimulus and send signals to the flagella.

The rings: a. are curved structures into which each filament inserts. b. anchor the flagellum to the cell membrane. c. are covered by a membrane. d. are comprised of globular proteins called flagellin.

b. anchor the flagellum to the cell membrane.

As a bacterium approaches a food source, one would expect: a. flagella to stop spinning. b. runs to become more frequent. c. flagella to rotate clockwise more frequently. d. tumbles to become more frequent. b. runs to become more frequent.

b. runs to become more frequent.

Due to a vast array of nutrients, microorganisms are often capable of sustaining exponential growth in the environment.

biofilms are composed of only one species at a time

What structural part of a bacterial flagellum is composed of flagellin? a. Rod b. Basal body c. Filament d. Hook

c. Filament

Pathogenic bacteria: a. are unique because they have a membrane covering the filament. b. have a unique basal body structure. c. can be identified and classified by differences in their flagellar proteins. d. do not have flagella.

c. can be identified and classified by differences in their flagellar proteins.

Which of the following statements about bacterial flagella is true? a. Bacteria can only rotate flagella clockwise. b. Bacteria can only rotate flagella counterclockwise. c. flagella can rotate 360 degrees. d. Bacteria work by undulating.

c. flagella can rotate 360 degrees

The process of generating ATP using a proton gradient is referred to as

chemiosmosis

Which of the following statements about glycolysis is true? A) All cells perform glycolysis. B) Glycolysis produces glucose. C) Glycolysis is the main source of NADH in the cell. D) Glycolysis is also called the Embden-Meyerhof pathway.

D) Glycolysis is also called the Embden-Meyerhof pathway.

Where does glycolysis and the citric acid cycle occur in bacterial cells?

cytoplasm All of the steps of cellular respiration, except those related to the electron transport chain and ATP synthase, take place in the cytoplasm of bacterial cells.

What occurs at the bridge step?

Decarboxylation of pyruvic acid

Which of the following is an example of a biofilm?

dental plaque

Correctly identify and label the types of molecules and the groups of organisms that obtain their energy from different types of metabolic pathways.

energy source: chemicals --> chemotrophy --> chemorganotrops --> organic chemicals --> ATP energy source: chemicals --> chemotrophy --> inorganic chemicals --> chemolithotrophs --> ATP energy source: light -->phototrophy -->phototrops --> ATP *all produce ATP

Bacterial degradation of cellulose and fermentation of glucose occur in the rumen of cows, sheep and other ruminant animals. The main source of energy for the fermenters is __________, while the main source of energy for the ruminant is __________.

glucose, volatile fatty acids

Select the correct sequence of steps as energy is extracted from glucose during cellular respiration.

glycolysis → acetyl CoA → citric acid cycle → electron transport chain Glycolysis produces pyruvic acid, which is then converted to acetyl CoA (the bridge step). Acetyl CoA then enters the citric acid cycle. Electron carriers bring electrons from the first three steps to the electron transport chain where ATP is made via oxidative phosphorylation.

A population of metabolically related microorganisms is called a(n)

guild

The use of amino acids to make proteins

is an example of anabolism.

In metabolism, energy that is not used

is given off as heat.

Ecological theory states that for every organism there is at LEAST one ________, and the microenvironment where the organism is most successful is called the ________.

niche; prime niche

Cells within a biofilm excrete an adhesive matrix primarily composed of ________ but can also contain nucleic acids as well as proteins.

polysaccharides

The metabolic process of ammonification ________ ammonia.

produces

Most nitrogen-fixing bacteria symbiotically associated with plants are called

rhizobia

Plant root nodules are

sites where nitrogen fixation occurs

Axial filaments are found on

spirochetes

Glycolysis literally means

sugar splitting

During an oxidation reaction...

the donor molecule loses an electron and becomes oxidized.

Peritrichous bacteria make a run when A. the flagella turn counterclockwise and separate. B. the flagella turn clockwise and separate. C. the flagella turn clockwise and become bundled. D. the flagella turn counterclockwise and become bundled.

the flagella turn counterclockwise and become bundled.

In the soil, oxygen concentrations are highly variable even within a soil particle. The center of the particle may be anoxic even if the outer portions are oxygen rich. In this context, facultative anaerobes could be found

throughout the particle.

How many net ATPs can be made from one molecule of glucose in glycolysis?

two

According to the animation, what does oxygen get reduced to at the end of the electron transport chain?

water

Which of the following is NOT a step in bacterial cell division?

Disappearance of nuclear envelope

A microbial population can contain several microbial communities.

False

Starting with three cells, how many cells would result from three rounds of replication?

24

Put the following steps of bacterial replication in the correct order, starting from a parent cell. Cell elongation Septum formation Chromosome replication Separation of daughter cells

3, 1, 2, 4

Based on the animation, how many electron carriers are reduced in the Krebs cycle only?

4

If you begin with six cells, how many cells would you have after three rounds of division?

48

Which of the following scenarios is an example of bacterial motility?

A bacterium moving towards a food source

A population consists of

all of the individuals of one species in the same area.

The reactions involved in producing larger compounds from smaller compounds is called:

anabolism

The rumen is an ________ habitat that depends on ________ to digest cellulose for ruminant animals.

anaerobic / cellulolytic and fermentative bacteria

How are Gram-positive and Gram-negative flagella different? a. A Gram-positive flagellum does not have a membrane covering its filament; A Gram-negative flagellum does. b. A Gram-positive flagellum has only two rings in its basal body; Gram-negatives each have four. c. Each Gram-positive flagellum contains a hook; gram-negatives do not. d. Flagella are only found in Gram-negative bacteria

b. A Gram-positive flagellum has only two rings in its basal body; Gram-negatives each have four.

A reaction that involves the transfer of electrons from one molecule to another is referred to as

a redox reaction.

What is the correct general equation for cellular respiration?

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP energy Cellular respiration extracts energy from glucose (C6H12O6) to produce smaller energy packets (ATP).

Where does the energy required for anabolic reactions come from?

Catabolic reactions

What carbon molecules remain at the end of glycolysis?

Pyruvic acid

Which of the following statements about fermentation is true?

It is an alternative way to return electron carriers to their oxidized state.

What is the fate of the NAD+ newly regenerated by fermentation?

It returns to glycolysis to pick up more electrons.

What is the role of pyruvic acid in fermentation?

It takes the electrons from NADH, oxidizing it back into NAD+.

Which of the following is an acid produced by fermentation?

Lactic acid and propionic acid

Which of the following types of bacterial cells would have flagella located at only one end of the cell?

Lophotrichous and monotrichous

Which of the following statements regarding redox reactions is true?

Redox reactions involve an oxidation reaction coupled with a reduction reaction.

Which step of binary fission is the reason for genetically identical daughter cells?

Replication of the bacterial chromosome

Which of the following types of bacterial cells would have only a single flagellum?

Monotrichous

Taxis is

Movement toward or away from a stimulus.

What is the major reservoir of stable nitrogen?

N2

According to the animation, which compounds provide electrons to the system?

NADH and FADH2

Nitrogen fixation results in the

Nitrogen gas being converted into nitrate or ammonium addition of biologically available N to an ecosystem.

How long does it take for the daughter cells from one round of replication to replicate themselves?

No time is required -- they are fully mature and ready to divide immediately after separation if conditions are right.

Which of the following terms refers to a bacterium moving towards a light source? Negative phototaxis Positive phototaxis Negative chemotaxis Positive chemotaxis

Positive phototaxis

What enables the copied chromosomes to separate during binary fission?

The chromosomes are attached to different parts of cell membrane, which elongates and thus separates the chromosomes.

According to the animation, what does the electron transport chain do to the concentration of hydrogen ions (protons)?

The concentration of protons is higher outside the membrane than inside.

Why is reduction the term used to describe the gain of an electron?

The electron acceptor's net charge decreases.

What would happen if the septum did not form during binary fission?

The parent cell would now have two copies of the chromosome.

What is the fate of metabolites during respiration?

They are oxidized completely to carbon dioxide and water.

Which statement describes the citric acid cycle?

This process produces some ATP and carbon dioxide in the mitochondrion. The citric acid cycle breaks down carbon molecules, releasing carbon dioxide and forming some ATP.

Which statement describes glycolysis?

This process splits glucose in half and produces 2 ATPs (via substrate-level phosphorylation) for each glucose. In glycolysis, glucose is split into two molecules of pyruvic acid. The released energy is stored in ATP and the electron carrier NADH.

Which statement describes the electron transport chain?

This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. In the electron transport chain, electrons move from one electron carrier to another, eventually reaching oxygen. The released energy is used to make ATPs.

An ecosystem includes both the living organisms and abiotic materials that function together.

True

Tumbles occur when the flagella rotate clockwise. the flagella stop rotating. the flagella rotate counterclockwise. the flagella undulate.

Tumbles occur when the flagella rotate clockwise

What results when a single bacterium reproduces?

Two genetically identical daughter cells