The Kingdoms Of Life (Chpt 19, 20, 21, 22) Flashcards
Taxonomy
Classification and identification of living organisms
Classification
Placing organisms into groups based on similar characteristics
Species
A group of organisms capable of interbreeding naturally to produce fertile offspring
Prokaryotic cells
Do not posses a nucleus or membrane bound organelles
Eukaryotic cells
Have a nucleus and membrane bound organelles
Micro-organisms
Small living things
DIAGRAM OF BACTERIA
Shapes of bacteria & examples
Round → pneumonia
Rod → tetanus
Spiral → syphilis
What name is given to bacterial reproduction?
Binary fission
Steps in bacterial reproduction
• DNA replicates
• cell elongates
• DNA moves to each side
• cell splits in two
• two identical daughter cells produced
What causes endospore formation in bacteria?
Unfavourable conditions
Eg drought
Steps in endospore formation (bacteria)
• contents of cell shrinks
• chromosomes replicate
• tough outer coat formed within cell around genetic material
Factors affecting growth rate of bacteria
Temperature
pH
Solute concentration
Oxygen concentration
Antibiotic
Chemicals produced by microorganisms that stop the growth of or kill other microorganisms
What causes antibiotic resistance?
Misuse of antibiotics
Mutations
Pathogenic bacteria
Disease causing bacteria
Beneficial uses of bacteria
• used to make antibiotics
• produce yogurts & cheese
• symbiotic bacteria in gut
Harmful uses of bacteria
• cause animal & plant disease
• cause food decay
GROWTH CURVE OF BACTERIA
Lag phase - adapting to environment
Log phase - rapid growth, abundant resources
Stationary phase - birth rate = death rate
Death phase - decline due to competition
Survival phase - small number survive as spores
Bioprocessing
The use of microorganisms to form useful products