Bacteria

Question 1

Bacteria are what type of cell?

Answer 1

prokaryotic

Question 2

Humans are what type of cell?

Answer 2

Eukaryotic

Question 3

What is the size of bacteria cells?

Answer 3

Most bacteria range in size from less than 1μm

they are 10-100 times smaller than our cells

Question 4

What allows bacteria cells to reproduce quickly?

Answer 4

Because of their high surface to volume area

Question 5

What are the parts of a bacteria cell?

Answer 5

Envelope (outside surface of the cell)
Structures outside the envelope
Cytoplasm

Question 6

What does the envelope contain?

Answer 6

the bacterial cell can have as many as three layers in its envelope
plasma membrane: found in Gram –negative and Gram-positive bacteria always made of phospholipids

cell wall: found in Gram-negative and Gram-positive bacteria always made up of peptidoglycan

outer membrane: found in Gram-negative bacteria only

Question 7

What does the cell wall do?

Answer 7

all bacteria except mycoplasmas have a rigid, strong cell wall which functions to:

• give the cell its shape
• withstand turgor pressure (water pressure) (cell does not burst due to influx of water from hypotonic environment)

Question 8

What is the cell wall made of?

Answer 8

peptidoglycan

glycan: carbohydrate
peptido: peptide

Question 9

How do the cell walls of gram + and gram - bacteria differ?

Answer 9

Gram-negative bacteria have only a single layer of peptidoglycan. *Gram - negative has a much thinner cell wall (peptidoglycan layer).
E-coli is gram negative

the cell wall of Gram-positive bacteria consists of many layers of peptidoglycan
*Has a much thicker cell wall

Question 10

Outer membrane is found where?

Answer 10

only in gram - bacteria

has 2 layers of phospholipids: inner is hydrophobic and outer is hydrophilic

Question 11

What does porin in the outer membrane do?

Answer 11

allows important nutrients, 02 and H20 to pass through

Question 12

lipid A a component of lipoprotein acts as a endotoxin to humans how?

Answer 12

produce symptoms: chills, fever, aches, weakness

in extreme cases septic shock

Question 13

When do endotoxins take effect?

Answer 13

When the gram - bacteria die and the cell undergoes lysis (ruptures)

Question 14

What is periplasm?

Answer 14

lies beneath the outer membrane of Gram-negative bacteria; filled with a gelatinous material containing proteins that are involved in facilitating the movement of nutrients into the cell

Question 15

What is the plasma membrane?

Answer 15

• phospholipid layer in direct contact with cell wall
• only part of the envelope surrounding mycoplasmas
• produce ATP in bacteria cells.

Question 16

What is a mycoplasma?

Answer 16

bacteria without a cell wall

Question 17

What structures are outside the envelope?

Answer 17

capsule, flagella, Axial Filaments, pilus, cytoplasm, nucleoid region, ribosomes, plasmids, endospores

Question 18

What does the capsule do?

Answer 18

• is a viscous, sticky, gelatinous substance outside the envelope of certain species of bacteria
• the capsule contributes to the bacterial virulence b/c it can protect the pathogenic bacteria from phagocytosis by the host’s cells.
• aids in the attachment of the bacteria to the host’s cells

Question 19

What does the flagella do?

Answer 19

movement of cell

Question 20

What does the axial filament do?

Answer 20

axial filaments cause the cell to move in a characteristic corkscrew fashion

Question 21

What does the pilus do?

Answer 21

hair like structures

allow bacteria to stick to host cell

sex pilus: join two bacteria transfer DNA from one cell to another

Question 22

What does the cytoplasm do?

Answer 22

prokaryotic cells is less complex than that of eukaryotic cells b/c of the absence of the various membrane-bound o organelles

Question 23

What does the nucleoid region do?

Answer 23

• contains DNA of bacteria (not surrounded by nuclear envelope)

A bacterium contains a single molecule of double-stranded DNA, known as the bacterial chromosome.

The bacterial chromosome is attached to the plasma membrane.

Question 24

What do ribosomes do?

Answer 24

protein synthesis

Question 25

plasmids?

Answer 25

not essential for survival of bacteria

carry antibiotic resistant gene
produce toxins
synthesis of enzymes
can be transferred from one bacterium to another

Question 26

endospores?

Answer 26

DNA surrounded by peptidoglycan and protein

they can withstand heat, lack of water, and exposure to toxins for many years.

they can become alive after many dormant years

Question 27

bacteria cells don’t have a nucleus

ribosomes: synthesize proteins
penicillin: can break down cell wall

Answer 27

.

Question 28

Nucleus?

Answer 28

Store Dna

Question 29

Nucleolus?

Answer 29

Inside nucleus: ribosome and rna synthesis

Question 30

Rough er?

Answer 30

Protein synthesis

Question 31

Smooth er?

Answer 31

Lipid synthesis + detoxifies cells

Question 32

Golgi body?

Answer 32

Sorts/prepared products for exocytosis

Question 33

Mitochondria?

Answer 33

Atp production + consume O2

Question 34

Ribosomes?

Answer 34

Synthesize protein

Question 35

Plasmid?

Answer 35

Gene for antibiotic resistance

Question 36

Nucleoid region?

Answer 36

Carries dna

Question 37

Flagella?

Answer 37

Movement of cell

Question 38

Pili?

Answer 38

Help adhere

Question 39

Endospores?

Answer 39

Highly resistant toxins