Lecture 3

Question 1

Characteristics of prokaryotes

Answer 1

unicellular, small, lack membrane-bound organelles, non-nuclear chromosomal DNA, chromosomal circular DNA, occasionally plasmids

Question 2

characteristics of eukaryotes

Answer 2

multicellular, large cells, membrane-bound organelles, well-defined nucleus, DNA as chromosomes, some fungi have plasmids

Question 3

Organelles in a bacterial cell

Answer 3

EPS, peptidoglycan cell wall, cell membrane, plasmid/chromosomes, cytoplasm, ribosomes, flagellum

Question 4

The majority of plant pathogenic bacteria are

Answer 4

facultative saprophytes, easy to culture, gram negative, rod-shaped, soil-living

Question 5

Some plant pathogenic bacteria are

Answer 5

obligate parasites with no free-living stage. impossible to culture

Question 6

Plasmids and Circular chromosomes carry information. What differs in the information each carries?

Answer 6

Chromosomal DNA carry essentials. Plasmids carry advantageous non-essential. They can carry viral resistances, virulence factors, coper resistance…

Question 7

Describe point mutation of streptomycin resistance

Answer 7

prevents binding to ribosomal target

Question 8

describe inactivation of streptomycin resistance

Answer 8

genes modifies streptomycin to nontoxic form

Question 9

Shapes of bacteria

Answer 9

filamentous (streptomyces), helical (spiroplasms), pleomorphic (phytoplasmas), rod (erwinia)

Question 10

Flagellum with 1 tail

Answer 10

monotrichous

Question 11

Flagellum with many tales on one side

Answer 11

lophotrichous

Question 12

flagellum with bi-polar tails

Answer 12

amphitrichous

Question 13

flagellum with surrounding tails

Answer 13

peritrichous

Question 14

What does gram positive mean?

Answer 14

plump cell wall/peptidoglycan. from outside to inside: pep –> plas. KOH test will not snot

Question 15

What does gram negative mean?

Answer 15

thin cell wall. from outside to inside –> mem –> pep –> plas. KOH test will snot (break cell wall)