The microbes commonly known as ________ are single-celled eukaryotes that are generally motile.

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The two large cells in this micrograph are classified as eukaryotic cells because

Which of the following is NOT an example of a fungus? A. Mushrooms B. Yeasts C. Molds D. Algae

Which of the following is a true statement concerning bacteria and archaea? A. Bacteria reproduce asexually, while archaea reproduce sexually. B. No archaea are known to cause disease in humans. C. Bacteria are often found in sufficiently dry environments. D. Bacteria and archaea have identical types of cell walls.

No archaea are known to cause disease in humans.

How are the bacteria and the archaea different from all the other cellular microbes?

A microorganism has the following characteristics: eukaryotic, multicellular, has cell walls, and grows in long filaments. What is its general classification?

The microbes commonly known as ________ are single-celled eukaryotes that are generally motile.

Which of the following is NOT a characteristic of viruses? A. they are composed of genetic material and protein. B. they are visible with a light microscope. C. they are acellular. D. they are smaller than prokaryotic cells. E. they are obligatory parasites.

they are visible with a light microscope.

Which of the following is NOT a characteristic of protozoa? A. they are single-celled organisms. B. most exhibit asexual reproduction. C. they are the microbes most similar to plants. D. they frequently possess cilia or flagella. E. they are eukaryotic organisms.

they are the microbes most similar to plants.

Which of the following is an incorrect pairing? A. algae: aquatic and marine habitats B. fungi: cell walls C. protozoa: multicellular D. viruses: acellular parasites E. prokaryotes: no nuclei

Whose experiments seemingly proved the existence of a "life force"?

Put the following steps of Koch's postulates in order: a. The suspected infectious agent must be isolated and grown outside the host. b. The suspected infectious agent causes the disease when it is introduced to a healthy, susceptible animal. c. The suspected infectious agent must be found in every case of the disease. d. The suspected infectious agent must be found in the diseased experimental host.

Microbes that can live in the presence or absence of oxygen are called

Which of the following scientists provided evidence in favor of the concept of spontaneous generation?

Which statement about Koch's postulates is false? A. Koch's postulates cannot be used to demonstrate the cause of all diseases. B. A suspected pathogen must be grown in laboratory. C. A suspected pathogen must be found in the majority of individuals with a particular disease. D. Koch's postulates involve the experimental infection of susceptible hosts. E. All of Koch's postulates must be satisfied before an organism can be proven to cause a particular disease.

A suspected pathogen must be found in the majority of individuals with a particular disease.

Which of the following statements about fungi is FALSE? A. fungi are photosynthetic. B. yeast are unicellular. C. fungi are eukaryotes. D. fungi have a cell wall. E. molds form hyphae.

1.    Which of the followingstatements about algae is FALSE?

A)  the group includes seaweeds and kelps.

B)  they are photosynthetic organisms.

C)  they provide most of the oxygen on Earth.

D)  they are important in the degradation of dead plants andanimals.

E)  they are a source of food for aquatic and marine animals.

D)  they are important in the degradation of dead plants and animals.

Microorganisms characterized by the absence of a nucleus are called:

The process of bringing a solid substance into the cell is known as ____________________.

which of the following processes would be affected by a lack of oxygen in a cell?
A. reproduction B. responsiveness C. growth D. metabolism

The presence of a glycocalyx would NOT be expected in which of the following? A. protozoan cells B. bacteria C. animal cells D. fungi

Which of the following statements about bacterial flagella is true? A. Flagella can rotate 360 degrees. B. Bacteria can only rotate flagella counterclockwise. C. Flagella work by undulating. D. Bacteria can only rotate flagella clockwise.

Flagella can rotate 360 degrees.

movement towards or away from a stimulus.

Which of the following terms refers to a bacterium moving towards a light source? A. Negative chemotaxis B. Positive phototaxis C. Negative phototaxis D. Positive chemotaxis

As a bacterium approaches a food source, one would expect

runs to become more frequent.

Why are receptors on the cell surface necessary for bacterial movement?

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

Which of the following molecules would be blocked by a cell membrane?

Hydrophobic molecules would enter a cell

through integral transport proteins.

What is a hallmark of passive transport across cell membranes?

It occurs along an electrochemical gradient, and may involve the use of transport proteins.

A positively charged sodium ion

would require the use of integral protein channels to pass through a cell membrane.

Which of the following statements regarding active transport is false? A. It requires ATP. B. It powers the diffusion of water across the cell membrane. C. It requires the use of a transport protein.

It powers the diffusion of water across the cell membrane.

why are phospholipid membranes good at keeping some molecules out and allowing others to freely pass?

they have both hydrophilic and hydrophobic regions

what are integral proteins involved in mostly?

how does water enter and exit a cell?

simple diffusion OR by using an integral transport protein

is a type of peripheral protein above that can be used as a receptor or in enzymatic functions.

Which of the following bacterial cell structures plays an important role in the creation of biofilms? A. pili B. fimbriae C. glycocalyces D. flagella E. both fimbriae and glycocalyces

both fimbriae and glycocalyces

Which of the following may have cell walls containing teichoic acids?

The cell walls of __________ contain tetrapeptides.

Both Gram-positive and Gram-negative bacteria

Which of the following have external structures containing a periplasmic space? A. Gram-negative bacteria B. Gram-positive bacteria C. Both Gram-positive and Gram-negative bacteria D. Archaea E. Eukaryotes

Which of the following prokaryotic cells contains an outer membrane? A. Gram-negative bacteria B. Gram-positive bacteria C. Both Gram-positive and Gram-negative bacteria D. Archaea E. All prokaryotes

A bacterial cell stains positive with the acid-fast stain. Which of the following is NOT true? A. It will be difficult to stain this cell with the Gram stain. B. It has a cell wall that contains waxy lipids. C. It has a cell wall that contains endotoxin. D. It may be a member of the genus Mycobacterium.

It has a cell wall that contains endotoxin.

Which of the following is NOT a component of bacterial cell walls? A. tetrapeptide B. peptidoglycan C. lipoteichoic acids D. my colic acid E. tubulin

Bacteria of the genus Mycoplasma are distinguished from other bacterial cells by

the absence of a cell wall.

Why is ATP necessary for active transport?

ATP provides energy to transfer material against its concentration gradient.

Which type of active transport protein moves two molecules into the cell at the same time?

Which transport protein employs transporters that move molecules only in one direction?

which transport uses one protein to transport 2 molecules

how is osmosis different from simple diffusion?

water movement is driven by the concentration of solutes rather than its own concentration

allow a variety of molecules to cross the cytoplasmic membrane

What will happen to a cell that is placed in a solution containing a high concentration of sugar, a molecule that cannot pass across the cell membrane?

The cell will lose its interior water, causing it to shrivel up and possibly die.

how is simple diffusion different from other types of passive transport?

simple diffusion does not require a permease

in a hypotonic solution there is a (HIGHER/LOWER) concentration of solutes

ATP is expended in which of the following processes?

both active transport and group translocation

Which statement concerning osmosis is FALSE? A. Cells placed in hypotonic solutions will gain water. B. Crenation results when cells are placed in a hypertonic solution. C. During osmosis, water crosses to the side of the membrane with a lower solute concentration. D. Osmosis requires a selectively permeable membrane. E. Osmosis stops when the system reaches equilibrium.

During osmosis, water crosses to the side of the membrane with a lower solute concentration.

The accumulation of glucose 6-phosphate inside a bacterial cell wall via phosphorylation of glucose is an example of

Hopanoids are found in __________ cytoplasmic membranes.

The process of facilitated diffusion requires an input of energy.

Which of the following would NOT be found in the cytoplasm of a bacterial cell? A. porins B. nucleoid C. ribosomes D.endospores

Formation of a biofilm may contribute to bacteria's ability to cause disease.

The cell walls of __________ contain peptidoglycan.

Cytoplasmic membranes of __________ are composed of phospholipids.

both bacteria and eukaryotes

Which of the following is a lipid that is common in eukaryotic cell membrane, but less so for prokaryotes?

Which of the following processes requires a carrier protein? A. endocytosis B. diffusion C. facilitated diffusion D. active transport E. both facilitated diffusion and active transport

both facilitated diffusion and active transport

Membrane rafts are found in the cytoplasmic membranes of

Endocytosis and exocytosis are means of transport used by

Short, hairlike structures used only by eukaryotic cells for movement are called

Which of the following is NOT associated with the nucleus of a eukaryotic cell? A. histones B. cristae C. chromatin D. nucleoplasm E. nucleolus

Which of the following statements about the ER is correct? A. The ER is a transport system within the cytoplasm. B. The smooth ER has ribosomes associated with it. C. The ER is a lipid storage organelle. D. The rough ER is the site of lipid synthesis. E. The smooth ER is a site of ATP synthesis.

The ER is a transport system within the cytoplasm.

Which of the following organelles is responsible for producing most of the ATP in a eukaryotic cell?

Chloroplasts differ from mitochondria in that they have

Light-harvesting pigments

Peroxisomes contain enzymes used to digest nutrients that have been brought into the cell through phagocytosis.

Eukaryotic ribosomes are composed of 60S and 40S subunits.

Lysosomes result from the endocytosis of food particles by eukaryotic cells.

in metabolism, energy that is not used

the reactions involved in producing larger compounds from smaller compounds is called

where does the energy required for anabolic reactions come from

the use of amino acids to make proteins is an example of 

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

During an oxidation reaction,

the donor molecule loses an electron and becomes oxidized.

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

The electron acceptor’s net charge decreases.

Which of the following statements regarding redox reactions is true? A. No metabolic reactions are redox reactions. B. They must either be oxidizing reactions or reducing reactions. C. They involve an oxidation reaction coupled with a reduction reaction. D. They are only seen in the electron transport chain.

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

any molecule that serves on electron acceptor will be.......

Which statement concerning cellular metabolism is FALSE? A. The goal of metabolism is reproduction of the organism. B. Macromolecules are converted into cell structures via catabolism. C. Enzymes are used in catabolic & anabolic reactions. D. Energy obtained from nutrients or light is stored in the bonds of ATP. E. ATP is used in the formation of macromolecules.

Macromolecules are converted into cell structures via catabolism.

anabolic reactions may be characterized as

forming large molecules from smaller molecules 

the molecule that an enzyme acts upon is known as its

Which statement about enzymes is FALSE? A. They form a temporary intermediate compound with a substrate. B. They are usually, but not always, proteins. C. They can be denatured if the pH of their environment is too high or too low. D. They function best at 37°C. E. They can be used to catalyze a chemical reaction over and over again.

They function best at 37°C.

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

Along the plasma membrane

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

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

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.

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

Which of the following can be the final electron receptor in anaerobic respiration in bacteria? A. pyretic acid B. nitrate C. sulfate D. both nitrate and sulfate E. both pyruvic acid and sulfate

The metabolic processes called fermentation:

use an organic molecule as a final electron acceptor

During chemiosmosis, electrons are pumped across a membrane to produce ATP.

Fermentation pathways provide a cell with an alternative way to regenerate NAD+ for glycolysis. B

Are protozoa also called prokaryotes?

Which of the following is a characteristic of protozoa?

How are the bacteria and the archaea different from all the other microbes?

Which of the following cellular microbes was the first to be genetically sequenced?