Prokaryotic Cell

Components of ALL living cells?

Plasma membrane, chromosomes, ribosomes, cytosol, and macromolecules

What are similarities and differences between prokaryotic and eukaryotic cells?

Both have: cell wall and DNA as genetic material

Prokaryotic have: no nucleus, 1/few circular chromosomes, no mitotic spindle (do not go through mitosis)

Eukaryotic have: nucleus, linear paired chromosomes, mitotic spindle (go through mitosis)

What is the glycocalyx? What are the two types of glycocalyces?

Gelatinous external layer made of polysaccharide or polypeptide; slime layer (loosely organized) and capsule (tightly attached)

What is biofilm? What are forming steps?

Microbial communities that form slime; 1 - free floating bacteria stick to surface, 2 - cells are growing + dividing and secreting EPS, 3 - EPS slime will attract other bacteria to join, 4 - multiple towers with channels as links are formed, 5 - some bacteria will detach from biofilm and stick to new surface and process repeat

Advantages for bacteria forming biofilms?

Sharing nutrients, shelter from harmful factors, helps with transfer of DNA from one bacteria to another

Similarities between flagella, fimbriae, and pili? Differences?

Similarities - contain some sort of protein

Flagella - have a filament arranged in several chains that intertwine

Fimbriae - short, straight, and thin

Pili - rigid and tubular

What are the different types of flagella? How do bacterial flagella move?

Filament, hook, and basal body; they move in a propeller-like way

Where is the DNA located in a prokaryotic cell? What is the difference between a bacterial chromosome and a plasmid?

The nucleoid; bacterial chromosomes have one circular, double stranded chromosome MEANWHILE plasmids have extrachromosomal genetic elements and carry non-crucial genes

List all different inclusions and what they store

Polysaccharide granules, lipid inclusions, and sulfur granules store energy reserves; carboxysomes store RuBisCo enzyme and gas vacuoles store protein covered cylinders

What is the function of a ribosome? What are the two subunits of a prokaryotic ribosome and what is the entire unit called?

Sites for protein synthesis; two subunits are called large (50s) and small (30s); whole thing is called complete prokaryotic ribosome (70s)

What are endospores? Why are they advantageous for prokaryotic cells to have? How do endospores form?

Tough, non-reproductive structures formed by certain bacteria to survive extreme environmental conditions; their longevity verges on immortality; they form through sporulation

What is function of cell wall in prokaryotic cells? What is disaccharide of the cell wall in bacteria? What is disaccharide of cell wall in archaea? What links rows of carbohydrates together?

Provide structural support; NAG; NAM (psedomurein); glycosidic bonds

Differences between gram positive and negative cell

Gram positive - thick layer of peptidoglycan, contain teichoic acids

Gram negative - thin layer of peptidoglycan, do not contain teichoic acids

Why is the genus Mycoplasmas considered atypical when regarding cell wall composition?

Completely lacks a cell wall and has only a cell membrane

Three parts to LPS found in outer membrane of gram negative cell an their functions?

O polysaccharide - functions as antigen

Core polysaccharide - provides stability structurally

Lipid A - an endotoxin embedded in the top layer

Structures that have antigens we can use to determine different strains of bacteria?

Cell wall, flagella, and capsule

Importance of gram staining? How can distinguish between gram positive and negative?

It distinguishes cells with a gram positive cell wall from those with a gram negative cell wall; gram positive retain crystal violet and stain purple MEANWHILE gram negative lose crystal violet and stain pink from safranin

Some ways we can target and damage bacteria cell wall?

Lysosine - enzyme that digests disaccharide in peptidoglycan

Penicillin - inhibits peptide bridges in peptidoglycan

What is the structure of plasma membrane? What are the three functions?

Fluid mosaic model (phospholipids, proteins, cholesterol, and carbohydrates); nutrient processing, site for energy reactions (ATP), and transport molecules into and out of cell

Which type of bacteria is more resistant to antibiotics l, chemicals, phagocytes, etc? What bacteria would be more sensitive to penicillin, gram + or gram - ?

Gram negative are more resistant; gram positive are more sensitive due to their thick peptidoglycan wall

Common shapes of bacteria and their arrangements?

Coccus (spherical), bacillus (rod-shaped), spiral; diplo (pairs), strepto (chains), tetrad (groups of four), and staphylo (grape - like clusters)

What is a virulence factor? What are examples of virulence factors ?

Any microbial molecules or trait that helps a pathogen include a host, evade immune defenses, cause disease, etc.; toxins, enzymes, and adhesion molecules