bacteria

Question 1

How are bacteria classified?

Answer 1

By shape or by gram-positive and gram-negative

Question 2

what is a gram stain?

Answer 2

a dye used to characterise bacteria

Question 3

what does the cytoplasm contain?

Answer 3

RNA, DNA and proteins plus other small molecules

Question 4

draw the structure of bacteria

Answer 4

check slide 4 lecture 4

Question 5

where are bacteria’s DNA found?

Answer 5

in the cytoplasm

Question 6

what are the different shapes of bacteria?

Answer 6

spherical
rod shaped
smallest cells
spiral cells

Question 7

what is the cytoplasm?

Answer 7

space inside the cell

Question 8

why do bacteria have cell walls?

Answer 8

osmotic pressure is created by the cytoplasm on the lipid bilayer
water can penetrate the lipid bilayer
lipid bilayer is not strong and ruptures easily

Question 9

which other organism has similar issue with the lipid bilayer as bacterium?

Answer 9

plant cells

Question 10

what does haploid mean?

Answer 10

one copy

Question 11

how does bacteria DNA duplication compare to other DNA duplication and why?

Answer 11

much faster (less time than copying 2 copies)
as DNA is circular and haploid in bacteria, and contain a single chromosome

Question 12

how long does it take E.Coli to replicate it’s genome?

Answer 12

about 30 minutes

Question 13

how do bacteria grow and adapt?

Answer 13

grow fast and and evolve to adapt to their environment quickly

Question 14

what are plasmids?

Answer 14

extra circular DNA that can have useful genes on there

Question 15

what are examples of genes in plasmids?

Answer 15

for antibiotic resistance

Question 16

do bacteria have organelles? if so, what are they?

Answer 16

no

Question 17

what structure do gram-positive bacteria have?

Answer 17

single membrane
thick cell wall made of cross-linked peptidoglycan

Question 18

why are gram-positive bacteria called this?

Answer 18

they retain the violet dye used in gram staining procedure

Question 19

what is an example of a gram positive bacteria?

Answer 19

bacillus anthracis

Question 20

what is an example of a gram-negative bacteria?

Answer 20

E.Coli

Question 21

what is the structure of gram-negative bacteria like?

Answer 21

two membranes separated by periplasmic space
outer leaf contains LPS

Question 22

what does LPS stand for?

Answer 22

lipopolysaccharide

Question 23

draw the structure of a gram-positive cell wall

Answer 23

check slide 6 lecture 4

Question 24

draw the structure of a gram-negative cell wall

Answer 24

check slide 6, lecture 4

Question 25

what do gram negative species' walls contain?

Answer 25

small amounts of peptidoglycan and LPS

Question 26

what are some differences of gram-positive and gram-negative bacteria?

Answer 26

gram negative are harder to control with antibiotics and have less peptidoglycan

Question 27

why are cell-surface appendages important?

Answer 27

for bacterial behaviour

Question 28

what are flagella for?

Answer 28

movement

Question 29

how do many bacteria swim?

Answer 29

using the rotation of helical flagella

Question 30

what are pili?

Answer 30

short protein appendages

Question 31

which are smaller: pili or flagella?

Answer 31

pili

Question 32

what can pili do?

Answer 32

adhere bacteria to surfaces

Question 33

what can straight pili do?

Answer 33

facilitate genetic exchange between bacteria

Question 34

how are pili and flagella kept to the cell surface?

Answer 34

anchored by large multi protein complexes

Question 35

what can a fraction of bacteria be?

Answer 35

pathogenic

Question 36

what does pathogenic mean?

Answer 36

disease causing

Question 37

how do pathogens differ from other species?

Answer 37

they have additional genes that confer their pathogenicity

Question 38

where are pathogens' additional genes found?

Answer 38

can be held onto a separate plasmid or integrated into the chromosome

Question 39

what is a significant property of bacteria?

Answer 39

highly resistant

Question 40

what are capsules sometimes known as?

Answer 40

slime layers

Question 41

how do capsules form?

Answer 41

using sugars

Question 42

what is the outer layer of capsules called?

Answer 42

glycocalyx

Question 43

what are spores resistant to?

Answer 43

heat, irradiation, cold can still be viable after over an hour of boiling

Question 44

what is an example of a spore and its use?

Answer 44

bacillus anthracis have been used in biological warfare

Question 45

draw the structure of spores

Answer 45

check slide 10lecture 4

Question 46

what is an example of where the human microbiota confined to?

Answer 46

skin

Question 47

what makes up most of the human microbiota?

Answer 47

bacterial cells

Question 48

what does the microbiota do?

Answer 48

influences our development and health in an example of a mutualistic relationship

Question 49

what is the microbiome?

Answer 49

combined genomes of the various microbial species

Question 50

how many genes does the microbiome have in comparison to human genome?

Answer 50

contain 100x more genes

Question 51

what can bacteria sometimes form?

Answer 51

capsules