An Introduction to Bacteria

Question 1

Chromosome structure and function

Answer 1

Circular DNA called plasmids and packaged by DNA binding proteins

Question 2

Cytoplasm structure and function

Answer 2

Gel-like matrix composed of water, enzymes, nutrients, wastes. Contains cell structures such as ribosomes, chromosome and plasmids

Question 3

Cell wall structure and function

Answer 3

Protects bacterium from damage and maintains cell shape and is rigid

Question 4

Ribosome structure and function

Answer 4

Found in cytoplasm and ER and involved in protein synthesis. Consist of 2 subunits (30s and 50s)

Question 5

Penicillin Binding Protein function

Answer 5

Enzymes involved in peptidoglycan synthesis and targets for the antibiotic penicillin

Question 6

Peptidoglycan structure and function

Answer 6

Back bone of cell wall which is a polymer that forms a mesh like layer outside the cell membrane

Question 7

lipopolysaccharide structure and function

Answer 7

Large molecules composed of O-antigen found on the outer membrane of Gram negative bacteria

Question 8

Capsule structure and fucntion

Answer 8

Virulence factor which protects bacteria from engulfment

Question 9

Flagella structure and function

Answer 9

Whip-like structure which allows motility of the cell

Question 10

Fimbriae structure and function

Answer 10

Short hair-like fibres that allow attachment

Question 11

Plasmid structure and function

Answer 11

Circular extrachromosal pieces of DNA found in the cytoplasm of the cell

Question 12

Bacteriophage structure and function

Answer 12

A type of virus that infects a bacteria

Question 13

Spores structure and function

Answer 13

Metabolically dormant structure produced during unfavourable conditions by the process called sporulation

Question 14

Spores are resistant to _____

Answer 14

Nutrition starvation, temperature, extreme Ph, antibiotics etc.

Question 15

Sporulation process

Answer 15

Mother cell —> Fore spore —> Mother cell engulfs fore spore –> calcium enters spore to remove water –> protein coat forms–> exosporium –> lytic enzymes destroy mother cell = spore release

Question 16

Sporulation process

Answer 16

Mother cell —> Fore spore —> Mother cell engulfs fore spore –> calcium enters spore to remove water –> protein coat forms–> exosporium –> lytic enzymes destroy mother cell = spore release

Question 17

Gram stain, stains Gram positive bacteria _____ and Gram negative bacteria ______

Answer 17

Purple and Red

Question 18

Cocci shape is ______

Answer 18

Spherical

Question 19

Bacilli shape is ______

Answer 19

Rod

Question 20

How do DNA in bacteria replicate

Answer 20

Binary Fission

Question 21

How does bacteria transfer DNA

Answer 21

Conjugation
Transformation
Transduction

Question 22

What are the 2 cycles of transduction

Answer 22

Lytic and Lysogenic cycle

Question 23

Burst host cell once replication is finished

Answer 23

Lytic

Question 24

Integrate with host chromosome and stay latent for a long period of time

Answer 24

Lysogenic

Question 25

Ways in which bacteria are identified

Answer 25

Anaerobic/aerobic
Gram positive/Gram negative
Bacilli/Cocci

Question 26

Detection and Culture methods for bacteria

Answer 26

Individual- Gram fluorescent dyes

Culture on solid medium such as agar