Micro Chapter 3

Mastering Micro. Review

peptidoglycans are composed of sugars and

amino acids

one chain of alternating NAGs and NAMs is connected to another chain via

tetrapeptides

One of the main differences between a gram-positive and a gram-negative bacterial cell wall is that the peptidoglycan portion of a gram-positive cell wall is ____ as compared to a gram-negative cell wall

thicker

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within the peptidoglycan layer, the cross bridges that connect the chains of alternating sugar molecules extend between

two N-acetylmuramic acid and molecules

The peptidoglycan cell wall of bacteria is most analogous to

a chain link fence

what role do the teichoic acids play within the cell wall of a gram-positive bacteria

they serve to stabilize the cell wall and hold it in place

The region between the outer and inner membrane of a gram-negative bacterial cell is known as the ___, and it is the location of enzymes that assemble peptidoglycan

periplasmic space

A patient is infected with gram-negative bacteria and is experiencing only mild symptoms. When the patient is given an antibiotic causing lysis of the bacterial cells, he suddenly experiences an increase in inflammation and fever, as well as a formation of blood clots. What explanation best describes what happened

the lysis of the cells release lipid A from the lipopolysaccharide layer

why is ATP necessary for active transport

ATP provides energy to transfer material against its concentration gradient

which type of active transport protein moves to molecules into the cell at the same time

symport

which transporting employees transporters that move molecules only in one direction

uniport and symport

which type of active transport proteins uses one protein to pump two different molecules

antiport and symport

tumbles occur when

flagella rotates clockwise

which of the following types of bacterial cells would have only single flagellum

monotrichous

Peritrichous bacteria make a run when

the flagella turns counterclockwise and become bundled

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 molecules would be blocked by cell membrane?

ions

hydrophobic molecules move across a membrane

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by passive transport directly across the membrane

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

it powers the diffusion of water across the cell membrane

what makes phospholipid membranes good at keeping some molecules out and allowing others to freely pass

they have both hydrophilic and hydrophobic regions

integral proteins are mostly involved in

transport function

how does water enter and exit a cell

by simple diffusion, or by use of an integral transport protein

a glycoprotein

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

which of the following scenarios is an example of bacterial motility

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a bacterium moving towards a food source

axial filaments are found on

spirochetes

which of the following statements about bacterial flagella is true

flagella CAN rotate 360 degrees

taxis is

movement towards or away from a stimulus

which of the following terms refers to a bacterium moving towards a light source

positive phototaxis

as a bacterium approaches, a food source one would expect

The receptor sense the stimulus and send signals to the flagella

why is no energy required in passive transport

the concentration gradient drives the movement

once equilibrium is reached

molecules move, but there is no net movement in a particular direction

which of the following would not move freely across the cytoplasmic membrane

positively charged hydrogen ions

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how is osmosis different from simple diffusion

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

nonspecific permeases

allow a variety of molecules across the cytoplasmic membrane

what will happen to a cell that is placed in a solution containing a high concentration of sugar 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

if a eukaryotic cell suffers damage, to which mitochondria, which of the following processes of life would be most immediately affected

Energy production

which of the following is NOT a basic process of life

sexual reproduction

using a microscope, you observe an amoeba moving toward a food source. This is an example of

responsiveness

which of the following statements concerning the characteristics of life is FALSE

reproduction is defined as an increase in the size of an organism

which of the following is not a characteristic of all living things

motility

which of the following is not a characteristic of a eukaryotic cell

can undergo transcription and translation simultaneously

which of the following organisms is a prokaryote

archaea

label the structures of this eukaryotic cell

bottom (cytoskeleton)

label the structures of this prokaryotic cell

A periplasmic space is found in which of the following

gram-negative cells ONLY

which of the following would contain teichoic acids

a gram-positive cell wall

The process of bringing a solid substance into a eukaryotic cell is known as

phagocytosis

which of the following processes requires a channel protein

both facilitated diffusion and active transport

eukaryotic cells, use a process, known as ____ to obtain liquid from their environment

pinocytosis

what is the composition of the peptidoglycan layers found in the cell wall of bacteria

short amino acid chains, NAG, NAM, and some lipid proteins

gram- positive cell wall characteristics

THICK layer of peptidoglycan

teichoic acids

single lipid bilayer membrane

stains PURPLE

gram-negative bacterial cell wall characteristics

periplasmic space

THIN layer of peptidoglycan

dual lipid bilayer protein

lipid A

stains PINK

The composition of a cell wall allows for the expansion and contraction of the cell wall in response to the gain loss of water from the cell, true or false

FALSE

a cell wall is a requirement for all living bacteria, true or false

FALSE

drag the description terms to the pictured bacterial shapes

MEMORIZE

bacterial flagella have a biological motor that spins within the cell wall, and is powered by ATP. this allows flagella to spin in a whiplike motion to propel a bacterium, true or false

FALSE