Ch.4: Functional Anatomy of Prokaryotic and Eukaryotic Cells Flashcards
4 chief characteristics of PROKARYOTES:
- DNA is NOT enclosed within a membrane and is usually singular circularly arranged
- LACK MEBRANE ORGANELLES
- Cell walls contain PEPTIDOGLYCAN
- DIVIDE BY BINARY FISSION
4 chief characteristics of EUKARYOTES:
- DNA is found in the cell’s nucleus within a nuclear membrane
- CONTAIN ORGANELLES
- Cell Walls if present are simple
- Cell division involves MITOSIS
List the 3 basic shapes of Bacteria
cocci (spherical)
bacillus (rod-shaped)
spiral
5 Different arrangements of Cocci include:
- DIPLOCOCCI (pairs)
- STREPTOCOCCI (chainlike pattern)
3, TETRAD (groups of four) - SARCINAE (cube-like)
- STAPHLOCOCCI ( clusters)
4 Different arrangement of Bacillus include:
- Single Bacilli
- Diplobacilli (pairs)
- Streptobacilli ( chains)
- Coccobacilli (oval and looks similar to cocci)
3 Different arrangement of Spiral include:
- Vibrios ( curved rods)
- Spirilla ( spiral, rigid bodies)
- Spirochetes ( corkscrew, helical and flexible)
Most bacteria are __________, that is they maintain a single shape
monomorphic
Bacteria’s such as Rhizobium and Corynebacterium are genetically __________, which means they can have many shapes not just one
Pleomorphic
What are the 5 Structures that all BACTERIA posses?
Cytoplasm 70s ribosomes Plasma membrane DNA Cell Walls
____________, is the general term used for substances that surround the cells. VISCOUS (sticky), gelationous and external to the cell wall. MADE INSIDE THE CELL and secreted into the cell surface. IMPORTANT COMPONENT OF BIOFILM(attachment)
Glycocalyx
________ organized and firmly attached to the cell wall. IMPORTANT IN CONTRIBUTING TO BACTERIAL VIRULENCE (phagocytosis), PROTECT FROM DEHYDRATION
Capsule
_________ ___________ _______: protects the cells within it, FACILITATES COMMUNICATION among the and enables the cells to survive by attaching to various surfaces in their environment. (biolfilm)
extracellular polymeric substance
_________; long filamentous appendages that propel bacteria . SOME PROKARYOTES HAVE IT.
flagella
6 types of distribution of Flagella on the cell:
- Atrichous (lack of)
- Peritrichous (everywhere)
- Polar (one or both end)
- monotrichous (only at one end)
- Lophotrichous ( tuft at one pole)
6 amphitrichous ( both ends)
3 Basic Parts of Flagella include:
- Filament: long outermost region (globular protein flagellin)
- Hook, wider connect the filament
- Basal Body: anchors the flagellum to the cell wall and plasma membrane
BASAL BODY: Gram Negative vs. Gram positive
Gram negative:contains TWO pairs of rings. (outer/inner)
Gram positive: only the inner pair is present
Each prokaryotic flagellum is a semirigid, helicial structure that moves the cell by…?
rotating from the basal body
When a bacterium moves in one direction for a length of time the movement is called ______ or ______ and then during an abrupt change it is called _____
run or swim
Tumble
_______ are usually longer than Fimbrae and number only one or two per cell. INVOLVED IN MOTILITY AND DNA TRANSFER.
PILLI
________ _______: a pilus extends by the addition of subunits of pilin, makes contact with a surface or another cell then retracts
Twitching motility
4 Major Functions of the Cell Wall
- Prevent bacterial cells from rupturing
- helps maintain the shape
- serves as an anchorage for the flagella
- contributes to the ability of some species to cause diseases
The bacterial cell wall is composed of a macromolecular network called __________:
peptidoglycan
Peptidoglycan consist of repeating dissachrides attached by polypeptides to form a lattice that surrounds and protects the entire cell. The dissachride portion is made up of monosaccharides called _____ and ______
NAG and NAM
Adjacent rows are linked by __________, always includes tetrapeptide side chains, which consist of four amino acids attached to NAMs in the backbone. Amino acids come off the NAM not NAG
polypeptide
2 CHARACTERISTICS OF A GRAM-POSITIVE CELL WALL:
- Thick Peptidoglycan layer
2. Contain TECHOIC ACID (negative charge)
4 Major Functions of Techoic Acid:
- bind and regulate the movement of cations into and out of the cell
- cell growth
- prevent extensive wall breakdown (lysis)
- antigenic specifity
4 CHARACTERISTICS OF A GRAM-NEGATIVE CELL WALL:
- thin layer of peptidoglycan
- an outer membrane and plasma membrane
- periplasm
- Consist of LIPOPOLYSACCHARIDE on its outer membrane.
Major function of Lipopolysaccharide:
- endotoxin
- provide stability
- specific antigens
Among prokaryotes certain types of cells have no walls or have very little wall material. These include members of the genus ________. Their plasma membranes are unique among bacteria in having lipids called STEROLS, which are thought to help protect them from lysis
Mycoplasma
The __________ __________, is thin structure lying inside the cell wall and enclosing the cytoplasm of the cell
Cytoplasmic membrane
4 Key Functions of the Cytoplasmic membrane
1, Permeability barrier (highly selective)
- Protein anchor (site of many proteins)
- breakdown of nutrients
- production of energy
Gram-Positive cells stain _______ while Gram Negative stain _________
Purple
Pink
When essential spores are depleted, certain gram-positive bacteria such as those of CLOSTRIDIUM AND BACILLUS form specializing “resting” cells called _______
Endospores
The process of endospore formation within a vegetative cells takes several hours and is known as ?
Sporulation or Sporogenesis
5 Steps of Sporulation
- Replicate DNA
- A septum forms, isolate the chromosome
- The larger compartment engulfs the smaller form creating a forespore
- Peptidoglycan layer forms between membranes. Spore coat forms
- The mother cell is disintegrates and the endospore is free from the cell
Characteristics of an Endospore:
RESISTANT TO:
heat, UV, Chemicals, drought
Dehydrated and impermeable
___________, the process where an endospore returns to its vegetative state. TRIGGERED by physical or chemical damage to the endospore’s coat
GERMINATION
