4.1 - The microbial world Flashcards
microbiology
study of living things that are too small to be seen with unaided eye (microbes)
3 habitats that support majority of microbial diversity (3)
- soil
- fresh water
- seawater
microbe benefits (5)
- environment
- food
- bodily
- medical
- technology
microbe environmental benefits (2)
- decompose natural wastes and dead animal/plant matter
- produce nutrients for plants
microbe bodily benefits (2)
- gut flora
- regulates production of nutrients
Harmful effects of microbes?
human, animal and plant diseases
eukarya microorganisms (3)
- fungi
- protozoa
- algae
prokaryotic microorganisms (3)
- bacteria
- archaea
- viruses
features of bacterial taxonomy (4)
- shape
- metabolic activity
- pathogenicity
- nutritional requirements
key components of bacterial cell (6)
- rigid cell wall
- glycocalyx
- genetic material free floating in cytoplasm
- smaller rings of DNA called plasmids
- possesses ribosomes for protein synthesis
- flagella
role of rigid cell wall in bacteria (2)
- helps determine shape
- forms protective barrier
main component of bacteria cell wall
peptidoglycan
genetic material free floating in cytoplasm (bacteria)
found in single chromosome concentrated in a nucleoid
glycocalyx (3)
- sticky layer surrounding cell
- may form a capsule (organised and strongly attached)
- may form slime layer (disorganised and loosely attached)
plasmids (smaller rings of DNA in bacteria) (2)
- can self replicate
- contain non-essential genes that may confer advantage
gram negative bacteria (2)
- double plasma membrane separated by periplasm
- thin peptidoglycan layer covered by outer membrane, has porins and LPS (endotoxin)