Prokaryotic%20cellsS10

Prokaryotic%20cellsS10 - PROKARYOTIC CELLS Chapter 4...

Info iconThis preview shows pages 1–16. Sign up to view the full content.

View Full Document Right Arrow Icon
PROKARYOTIC CELLS Chapter 4
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
EUKARYOTES vs PROKARYOTES: What’s the difference? Chemically similar Both have the same macromolecules Some type of cell (plasma) membrane Prokaryotes have peptidoglycan in cell walls Genetic material is made up of nucleic acids Both use DNA as the genetic material Prokaryotes: No membrane-bound organelles or histones All cells replicate Prokaryotes replicate by binary fission
Background image of page 2
PROKARYOTES All are unicellular organisms Have no nuclear membrane Lack organelles Divide by binary fission Divided into 2 large groups called domains There are 3 domains: 2 prokaryotic + 1 eukaryotic Archaea (archaeobacteria) Bacteria (eubacteria) Eukarya 1. SIZE, SHAPE, ARRANGEMENT 2. NUTRITIONAL REQUIREMENTS 3. BIOCHEMICAL ACTIVITIES 4. STAINING CHARACTERISTICS
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
SHAPE Three basic shapes Spherical = coccus (cocci) Rodlike = bacillus (bacilli) Spiral = from comma-shaped (vibrio) to rigid, wavy-shaped (spirillum) and corkscrew shaped (spirochete) Variations are found Short rods = Coccobacillus Some may not fit any particular category Irregular, lobed or spindle-shaped Square Size and shape may vary with availability of nutrients
Background image of page 4
ARRANGEMENT Coccus (cocci) Single Diplococci Tetrad Sarcinae Streptococci Staphylococci Bacillus (bacilli) Single Diplobaccilli Coccobacilli
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figures 4.1a, 4.1d, 4.2b, 4.2c Arrangements Pairs: Diplococci, diplobacilli Clusters: Staphylococci Chains: Streptococci, streptobacilli
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
GENERIC PROKARYOTIC CELL OUTSIDE CELL WALL Eubacteria: Peptidoglycan Archae: Pseudomurein CYTOPLASMIC (PLASMA) MEMBRANE INSIDE Cytoplasm, nuclear body, inclusions & granules, ribosomes, plasmids & endospores
Background image of page 10
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
GLYCOCALYX General term: CHO containing, surrounds cell Polysaccharide, polypeptide or both sticky External to cell wall of some bacteria Found in both Gram +ve and Gram -ve bacteria Two types: Capsule if it is organized and firmly attached Slime layer if it is unorganized and loosely attached Functions: virulence factor Attachment to surfaces Protection from phagocytosis by WBCs Detected with NEGATIVE STAINS
Background image of page 12
BIOFILMS When organisms exist as clumps of cells that are attached to each other and to solid surfaces they form BIOFILMS, a complex collection of microorganisms Glycocalyx is a very important part of biofilms These glycocalyxes are called extracellular polymeric substances The EPS protects cells, allows for communication, and attachment to surfaces Biofilms can be beneficial or harmful Bacteria in biofilms are usually resistant to antibiotics and become more virulent Examples: on tongue, teeth, on rocks, clog pipes, in serious infections such as UTI, endocarditis etc…
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 1.7 Normal Microbiota on Human Tongue
Background image of page 14
Figure 1.8 Biofilms
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 16
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 58

Prokaryotic%20cellsS10 - PROKARYOTIC CELLS Chapter 4...

This preview shows document pages 1 - 16. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online