Chapter 3,11,5,6 – Flashcards

Growth: an increase in size

Reproduction: an increase in number

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

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

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

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

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

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

Having two or more flagella at one end

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.

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.

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)

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).

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.

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

1. Harvest light engergy in photosynthetic Prokaryotes

2. Energy Storage- maintain concentration and electrical gradient

3. Selectively permeable- proteins allow substances to cross membrane

Passive Processes

1. Simple diffusion
2. Facilitated diffusion
3. Osmosis

Active Processes

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.

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

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

Cytosol- is the liquid portion of the cytoplasm

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

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

Plays a role in forming the cell's basic shape

• Do not have peptidoglycan
• contains variety of specialized polysaccharides and proteins
• Gram + stain= purple
• Gram - stain = pink

Cocci- sperical

Baccilli- rod

Spiral-

Spirilla- stiff

Spirochetes- flexible

coccobacillus- intermediate between cocci ; bacilli