Micro: Ch 5 Bacterial Cell Structure And Function

Front 1

Bacillus

Back 1

rod shaped

Front 2

coccus

Back 2

spherical

Front 3

vibrio

Back 3

curved or comma shaped

Front 4

spirochete

Back 4

helical

Front 5

pleomorphic

Back 5

more than one shape

Front 6

diplo-

Back 6

linking of cells in twos

Front 7

tetra-

Back 7

linking in fours

Front 8

staphylo-

Back 8

clustered like grapes

Front 9

strepto-

Back 9

in chains like a necklace

Front 10

Explains the functions of the cell (or cytoplasmic) membrane

Back 10

The cytoplasmic membrane defines the inside and outside of a cell. It contains transporters that pump desirable chemicals into cell using the cell's energy resources. It also prevents undesirable chemicals from entering the organism.

Front 11

Describe the structure of peptidoglycan.

Back 11

The structure of peptidoglycan is like a fishnet because the long polymers of glycan are cross-linked by shorter pieces of peptides.

Front 12

Name two biologically active items that destroy the bact cell wall

Back 12

lysozyme and PCN

Front 13

What struct component is unique to gram neg bact?

Back 13

An outer membrane is unique to gram neg bacteria.

Front 14

What major chemical is unique to an outer membrane?

Back 14

lipopolysaccharide is chemically unique to the outer membrane of gram neg bacteria

Front 15

How does peptidoglycan vary between gram pos and gram neg organisms?

Back 15

Gram pos orgs have many layers of peptidoglycan. Gram neg orgs have only one or a few layers of peptidoglycan

Front 16

What layer of gram pos and gram neg bacteria is the same? What layer is completely different?

Back 16

The cytoplasmic membrane is the same. The outer membrane is different because only gram neg bact have one.

Front 17

List four steps of the gram stain and the funct of each.

Back 17

1. stain with primary stain, crystal violet
2. fix the crystal violet with Gram's iodine so that is aggregates
3. Wash the aggregates from the porous gram neg bact with acetone-alcohol
4. Counterstain with safranin so the gram neg cells are readily visible.

Front 18

What is the chemical makeup of the structure that coats a bacterium?

Back 18

Polysaccharide is the coating's chemical makeup

Front 19

What is the function of the polysaccharide?

Back 19

The coating makes the bacterium slippery so that WBCs cannot capture and destroy it.

Front 20

Describe the cell cytoplasm

Back 20

The cytoplasmic compartment contains all the degradative and synthetic machinery to allow the cell to grow and make new copies of itself. It includes the cell's DNA, RNA, and proteins.

Front 21

Distinguish the bacterial chromosome from plasmids.

Back 21

The bact chromosome (like all chromosomes) contains thousands of genes, including those required for replication and gene expression. Some bacteria also contain plasmids, small pieces of DNA usually encoding fewer than fifty genes. Plasmids are often specialized, like those that code for resistance to a specific antibiotic.

Front 22

What are the sizes of a complete bacterial ribosome and its two major components in S units? Compare them to eukaryotic ribosomes.

Back 22

Prokaryotic ribosomes are 70S (one each of 30S and 50S subunits; eukaryotic ribosomes are 80S (one each of 40S and 60S)

Front 23

Why do some bacteria harbor inclusions or granules?

Back 23

The granules provide an energy source available for when cells have a special energy need.

Front 24

What are granules, or inclusions, composed of?

Back 24

Granules, or inclusions, are composed of polysaccharides or polyphosphates that contain much chemical energy.

Front 25

What are the most environmentally stable of all known life forms? What genera produce from?

Back 25

The most stable life forms are spores. Genera producing spores include the gram positive bacteria Clostridium and Bacillus.

Front 26

What is a streak plate? What task does it accomplish?

Back 26

The streak plate is a dish containing nutrient agar. It is used to grow individual cells into colonies to obtain pure isolates.

Front 27

What is a colony? Why do we obtain isolated colonies?

Back 27

A colony results when a single cell is streaked onto a plate in a well-separated manner so that the progeny can grow into a clump until they are sufficiently numerous to be seen by the naked eye. We obtain isolated colonies because they yield pure cultures in which every cell is identical, so the organism can be recognized.

Front 28

List four methods used in the identification of bacteria

Back 28

1. biochemical tests
2. immunological tests
3. genetic tests
4. direct DNA or RNA testing for org-specific sequences

Front 29

List possible bact appendages and their functs

Back 29

flagella- aid in motility
pili- gene transfer
fimbriae- attach to a given site

Front 30

List the three major components of bacterial flagella

Back 30

The three major components of bacterial flagella are the filament, hook, and basal body.

Front 31

How do bacteria produce a propelling force?

Back 31

Bacteria produce a propelling force by rotating their helical filaments against their watery environment.

Front 32

Name two possible benefits of motility to a pathogenic organism.

Back 32

Motility allows pathogens to spread and to escape capture by cells of the immune system.

Front 33

What benefit does chemotaxis confer upon a bacterium?

Back 33

Chemotaxis allows org to swim toward or away from chemicals.