Micro 210 Ch.3

Cells are?

living entities, surrounded by membrane, can grow, reproduce, metabolize

Prokaryotes

Cells WITHOUT nucleus (membrane bound organelles)

True or False: Prokaryotes have a Nucleus

False

Eukaryotes

Cells WITH nucleus (membrane bound organelles and are complex)

True or False: Eukaryotes have Nucleus

True

The external structures of Prokaryote Cells include:

Glycocalyces, Flagella, Fimbriae, Pili

True or False: All bacteria have a glycocalyx outside of cell envelope

True

What are purpose and characteristics of Glycocalyx?

Purpose: Prevent cells from drying up, Help pathogens evade detection

Characteristics: Sticky, made of polysaccharides and or polypeptides

True or False: There are 2 types of bacterial glycocalyces

True

What are the 2 types of bacterial glycocalyces?

Capsule and Slime layer

Characteristics of Capsule glycocalyces

Firmly attached

Anchored to cell wall

Chemicals can resemble human

Helps avoid detection

Characteristics of Slime layer glycocalyces

Loosely attached

Water soluble

Very sticky

Stick to various surfaces

Make biofilms

True or False: Do all Eukaryotes have glycocalyces

False

Glycocalyces are present in Eukaryotic cells only if?

the cell is lacking cell walls (animal cell and protozoan)

Glycocalyces are not present in Eukaryotic cells if?

the cell has cell walls (plant cells and fungi)

True or False: Eukaryotic glycocalyces are structurally organized as Prokaryotic capsules

False, they are messy

In Eukaryotes the purpose of glycocalyces is to?

Help anchor animal cells to each other

Strengthen cell surface

Provide some protection against dehydration

Cell to cell recognition and communication

Bacterial cell walls are made of?

Peptidoglycan, a complex polysaccharide

Peptidoglycan is composed of what sugars?

NAG and NAM sugars

Chains of NAG and NAM are linked together by?

Tetrapeptide crossbridges

Bridges may be covalently bonded to one another

Bridges may be held together by short connecting chains of amino acids

True or False: Archea and Eukaryotes don’t have Peptidoglycan

True

2 basic types of bacterial cell walls are?

Gram Positive (purple)

Gram Negative (pink)

How do you know the type of bacterial cell wall?

By conducting Gram stain

Stain with Crystal Violet (purple) and Safranin (pink)

Gram Positive bacterial cell wall characteristics:

Thick layer of peptidoglycan

Contain Teichoic acids

Retain crystal violet dye

Include Acid Fast bacteria