Intro to Microbiology
Chapter 1: The Main Themes of Microbiology
What is Microbiology?
• micron = small and biologia = study of living things
• Microbiology = study of small living things
• How small is “small”?
• What do we really mean by living?
• Working definition: Study of entities too small to be seen with the unaided human eye.
• (< 0.2 mm = 200 µm = 200,000 nm)
Types of Microbes Prokaryotes include Bacteria and Archaea Eukaryotes include Protista (Algae and Protozoa), Fungi, and Animalia Viruses are considered NON-LIVING
Size Range of Microbes
Relative Microbial Sizes
Characteristics of Living Organisms Metabolism – enzyme-catalyzed chemical reactions Bacillus cereus – Yes Bacteriophage T4 – No Reproduction – progeny formed sexually or asexually Bacillus cereus – Yes Bacteriophage T4 – Yes Differentiation – different cell types can occur Bacillus cereus – Yes Bacteriophage T4 – No Communication – signaling within and between cells Bacillus cereus – Yes Bacteriophage T4 – No Locomotion – relative movement of cell or organism Bacillus cereus – Yes Bacteriophage T4 – No Evolution – genetic change over time Bacillus cereus – Yes Bacteriophage T4 – Yes
Importance of Microbes
• The study of microbiology is relevant to our everyday life in many different ways. 1. Microbes are the earliest organisms found in the fossil record 2. They perform essential reactions in the environment 3. Microbes can be harnessed to work for us 4. They sometimes cause infectious diseases
Microbes in the Fossil Record
• The study of Evolutionary Biology
• Microbes first appeared about 3.5 billion years ago
• They were the only life forms on Earth for over 1.5 billion years
Microbes in the Environment Study of Environmental Microbiology Microbial photosynthesis account for most of the atmospheric oxygen on Earth Microbes are essential for decomposition of dead organisms Many biologically important
What is Microbiology?
• micron = small and biologia = study of living things
• Microbiology = study of small living things
• How small is “small”?
• What do we really mean by living?
• Working definition: Study of entities too small to be seen with the unaided human eye.
• (< 0.2 mm = 200 µm = 200,000 nm)
Types of Microbes Prokaryotes include Bacteria and Archaea Eukaryotes include Protista (Algae and Protozoa), Fungi, and Animalia Viruses are considered NON-LIVING
Size Range of Microbes
Relative Microbial Sizes
Characteristics of Living Organisms Metabolism – enzyme-catalyzed chemical reactions Bacillus cereus – Yes Bacteriophage T4 – No Reproduction – progeny formed sexually or asexually Bacillus cereus – Yes Bacteriophage T4 – Yes Differentiation – different cell types can occur Bacillus cereus – Yes Bacteriophage T4 – No Communication – signaling within and between cells Bacillus cereus – Yes Bacteriophage T4 – No Locomotion – relative movement of cell or organism Bacillus cereus – Yes Bacteriophage T4 – No Evolution – genetic change over time Bacillus cereus – Yes Bacteriophage T4 – Yes
Importance of Microbes
• The study of microbiology is relevant to our everyday life in many different ways. 1. Microbes are the earliest organisms found in the fossil record 2. They perform essential reactions in the environment 3. Microbes can be harnessed to work for us 4. They sometimes cause infectious diseases
Microbes in the Fossil Record
• The study of Evolutionary Biology
• Microbes first appeared about 3.5 billion years ago
• They were the only life forms on Earth for over 1.5 billion years
Microbes in the Environment Study of Environmental Microbiology Microbial photosynthesis account for most of the atmospheric oxygen on Earth Microbes are essential for decomposition of dead organisms Many biologically important