Bio440:questions1

Which type of transport is responsible for maintaining the voltage potential across the cell membrane?

antiport

Why are ATPases used in active transport?

They allow the systems to use the energy from ATP to power the transfer of material against the concentration gradient

What type of transport uses two transport proteins?

symport

Diffusion is used in which type of active transport?

symport

A uniport channel is used in which type of active transport system?

uniport and symport

A phospholipid bilayer that surrounds the cytoplasm of a prokaryotic cell is known as the _____________.

- cytoplasmic membrane.
- cell membrane.
- plasma membrane.

Peripheral proteins are involved in _______________.

1.receptors.
2. recognition sites.
3.enzymatic function.

Integral proteins _________________________.

span the entire lipid bilayer AND can be used in transport of molecules.

Which of the following is true?

- Water can freely pass through the cell membrane.
- Water can pass through a protein channel.
- Alcohol can pass freely through the cell membrane.

phosphate head

- It is composed of a glycerol and a fatty acid.
- It is hydrophilic.
- It is negatively charged.

Which of the following scenarios would be considered bacterial motility?

a bacterium swimming away from a high concentration of a toxic compound

Which of the following bacteria would have axial filaments?

treponema spirochetes in a syphilis chancre

Motility is _____________________________.

the ability of an organism to move by itself.

Which of the following are structures that make up the flagella?

1. hook
2. basal body
3. rod
4. filament

Flagellin _____________________.

forms helical chains that make up the filament.

How do eukaryotic flagella differ from prokaryotic flagella?

The filament of a eukaryotic flagellum is covered by a membrane

Which of the following is true regarding the basal body of bacterial flagella?

It may have two or four rings if the bacterium is Gram-positive or Gram-negative, respectively

Pathogenic bacteria _______________________.

can be identified and classified by differences in their flagellar proteins

Bacteria _______________________.

rotate the flagella 360 degrees to move through their

What is the role of the basal body?

1. to rotate the flagella 360 degrees
2. to cause the bacteria to make a run
3. to cause the bacterium to tumble

Which of the following terms refers to a bacterium moving toward a carbon source for food?

positive chemotaxis

A bacterium tumbles ___________________.

- more frequently as it moves toward a negative stimulus.
- when the flagella rotate clockwise.

How does a bacterium "know" when a light source is present?

The bacterium contains receptors that are sensitive to the light.

When a bacterial flagellum turns clockwise, ______________________.

the bacterium "tumbles.

Which of the following is correct for a peritrichous bacterium?

Flagella cover the cell surface

Amphitrichous bacteria ___________________.

have a flagellum at either end of the cell

Which of the following refers to a bacterium with a tuft of flagella at one end of the cell?

lophotrichous

Which of the following statements regarding bacterial flagella is true?

When the flagellum or flagella rotate counterclockwise, the bacterium runs

Which of the following is a property of axial filaments?

1. They are located between the cell membranes and outer membranes.
2. They do not protrude from the cell wall.
3. They cause the bacterium to corkscrew through the medium.

Spirochetes _______________________.

cause diseases like Lyme disease AND are spiral-shaped bacteria.

Axial filaments are composed of _______________.

endoflagella

Which of the following molecules can freely pass through the cytoplasmic membrane?

dissolved oxygen AND simple alcohols

Which form of transport might require an integral protein channel?

passive and active transport

What characteristic contributes to the membrane's ability to block the passage of some molecules?

hydrophobic cores

Passive transport does not require ATP because _________________________________.

it occurs along the electrochemical gradient.

Which of the following would require the use of a protein channel to assist in transport into and out of the cell

hydrophobic molecules

Which of the following are forms of passive transport?

1. diffusion
2. specific facilitated diffusion
3. nonspecific facilitated diffusion
4. osmosis

dissolved oxygen

- Dissolve oxygen moves from high concentrations to low concentrations.
- Dissolve oxygen will travel along its concentration gradient until equilibrium is reached.
- Dissolve oxygen can pass freely through the cytoplasmic membrane.

ATP is not required in passive transport of a chemical because ________________________________.

it occurs along that chemical's concentration gradient.

What is the function of permeases in specific facilitated diffusion?

It permits only one type of molecule to pass through the cytoplasmic membrane.

Osmosis is _______________________________.

the diffusion of water.

If a cell is placed in a high salt environment, what is likely to happen?

The cell will lose its interior water, shrivel up, and die.

Which of the following methods of passive transport does not require a permease?

- simple diffusion
- osmosis

Why does active transport require the expenditure of energy?

Active transport involves the transfer of material against the concentration gradient.

Which type of active transport protein is an example of coupled transport?

symport

What is a characteristic that all forms of active transport share?

They use transport proteins to facilitate the transport of material

Which type of transport protein brings material into and out of the cell?

uniport and symport

Which type of active transport transports only one type of material?

uniport

From which phrase is the term "prions" derived?

proteinaceous infectious particles

How do prions replicate?

They cause normal proteins to misfold into infectious proteins

How are prions different from other infectious agents?

They lack nucleic acid.