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Chapter 3,11,5,6
EXAM 1
32
Microbiology
Undergraduate 1
01/23/2013

Additional Microbiology Flashcards

 


 

Cards

Term

All living things share four processes:

Definition

Growth: an increase in size

Reproduction: an increase in number

Responsiveness: an ability to react to environmental stimul    Metabolism: controlled chemical reactions

 

Term
Who was Schwann & Schleiden?
Definition
Scientists that  believed that all living things are composed of cells
Term
What are the two types of living cells and their differences?
Definition

Eukaryotic

Have membrane surrounding their DNA.

Have internal membrane-bound organelles

Are larger, 10 nm in diameter

Have more complex structure

Composed of algae, protozoa, fungi, animals, & plants

 

Prokaryotic

Do not have membrane surrounding their DNA

Lacks a nucleus

Lacks various internal structures bound with phospholipid

Are small (less than 10 nm in diameter

have a simple structure

found in bacteria & archaea

 
 

 

 

 

 

Term
Glycocalyces
Definition

are gelatinous, sticky substances that surround the outsides a Prokaryotic cells.They are composed of polysaccharides, polypeptides, or both.

Term
What are the two main types of glycocalyces:
Definition

1. Capsule

  • composed of organized repeating units of organic chem
  • Firmly attached to cell surface
  • protects cells from drying out
  • may prevent bacteria from being recognized and destroyed by its host

2. Slim Layer

  • Loosely attached to cell surface
  • water soluble
  • protects cells from drying out
  • sticky layer allows prokayotes to attach to surfaces
 
Term

Flagella

Definition
  • Are responsible for movement
  • have long structures that extend beyond cell surface
  • are not present on all prokaryotes
Term

What are the 3 types of Flagella?

Definition
  1. Peritrichous- flagella covering the entire cell
  2. Single Polar-flagella found at the ends of a cell
  3. Tuft of polar
Term

What are lophotichous flagella?

Definition

Having two or more flagella at one end

Term

What are Endoflagella?

Definition

Are special flagella of spirochetes that tightlyy around the cell instead of protruding into envirnonment.

 

Also, form an axial filament that wraps around the cell and rotates, enabling it to corkscrew through its medium.

Term

Name two diseases caused by spirochetes?

Definition
Syphillis & Lyme disease
Term
What is taxis?
Definition
is the ability to respond to a stimuli / environment
Term
What is the flagella structure composed of?
Definition
Filament, hook, and basal body
Term
What is chemotaxis?
Definition
flagella move cell toward or away from stimuli such as chemicals
Term
What is phototaxis?
Definition
flagella move cell toward or away from stimuli such as light
Term
What are fimbriae?
Definition

are short, sticky, proteinaceous, nonmotile extensions of some bacteria that help cells adhere to one another and to substances in the environment. They serve as an important function in biofilms.

Term
What are biofilms?
Definition
slimy masses of bacteria adhering to a surface
Term
What are Pili?
Definition
are hollow, nonmotile tubes of a protein called that connect prokaryotic cells
Term
What is conjugation?
Definition
joining of two bacterial cells and mediate the movement of DNA from one cell to another
Term
What is the bacterial cell composed of?
Definition

Peptidoglycan, a complex polysaccharide composed of two alternating sugars called N-acetylglucosamine (NAG) &

N-acetylmuramic acid (NAM)

 

NAG & NAM are attached to other chains by a crossbridges of amino acids (tetrapeptides)

Term
What is the difference between Gram+ & Gram-?
Definition

Gram+ cells have a thicker layer of peptidoglycan that also contain teichoic acids. Their thick walls retains the crystal violet dye used in Gram staining.

 

Gram- cells have only a thin layer of peptidoglycan, outside of which a membrane containing lipopolysaccharide (LPS).

Term
What is the function of the cytoplasmic membrane?
Definition

separates the contents of the cell from the outside environment, but also controls the contents of the cell, allowing some substances to cross, while preventing the crossing of others.

Term
  What are the 3 important things to remember about Cytoplasmic Membranes?
Definition

1. Referred to as phospholipid bilayer; composed of lipids (hydrophobic tails & hydrophillic phosphate head) and associated proteins.

2. Approxiamtely 1/2 composed of proteins that act as recognition proteins, enzymes, receptors, carriers, or channels

3. Fluid mosaic model describes current understanding of membrane structure

Term
What do Prokaryotic cytoplasmic membranes do?
Definition

1. Harvest light engergy in photosynthetic Prokaryotes

2. Energy Storage- maintain concentration and electrical gradient

3. Selectively permeable- proteins allow substances to cross membrane

Term
What are major passive and active processes?
Definition

Passive Processes

  1. Simple diffusion
  2. Facilitated diffusion
  3. Osmosis

Active Processes

Term

Simple diffusion  &  Facilitated diffusion

Definition

Simple Diffusion- is the movement of chemicals down their concentration gradient, from an area of higher concentration to an area of lower concentration

 

Facilitated Diffusion- proteins act as channels or carriers to allow certain molecules to diffuse into or out of the cell along their electrochemical gradient.

 

 

Term
Osmosis
Definition

is the diffusion of water molecules across a selectively permeable membrane in response to differing concentrations of solutes.

Term
Symports, Antiports, & Group translocation
Definition

Symport- transport two substances in the same direction

 

Antiport- moves substances in oppposite direction

 

Group translocation- occurs only in some bacteria, causes a chemical change to the substances being transported

 

Term
Cytosol & inclusions
Definition

Cytosol- is the liquid portion of the cytoplasm

 

inclusion- are reserve deposits of lipids, starch or other chemicals with in the cytosol of bacteria

Term

Endospores 

Definition

Unique structures produced by some bacteria that are defensive strategy against unfavorable conditions 

Term
Cytoskeleton
Definition

Plays a role in forming the cell's basic shape

Term
What are Arcehael cell walls comprised of?
Definition
    • Do not have peptidoglycan
    • contains variety of specialized polysaccharides and proteins
    • Gram + stain= purple
    • Gram - stain = pink
 
Term
What are the  basic shapes of Prokaryotic cells?
Definition

Cocci- sperical

Baccilli- rod

Spiral-

Spirilla- stiff

Spirochetes- flexible

coccobacillus- intermediate between cocci & bacilli

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