In this video, we're going to begin our lesson on growing a pure culture. And so in a scientific lab or a microbiology lab, bacterial and archaeal cells are generally isolated, grown, and studied in what's known as a pure culture. And so a pure culture can be defined as a population of cells containing only one single species. And typically, these pure cultures are grown starting from a single colony. Now, a colony is a scientific term that's used to describe a group of approximately 1,000,000 cells or so. And colonies are going to be required to start a pure culture. And these pure cultures are again typically grown in a lab. And so if we take a look at our image down below over here at this pure culture, notice that we're starting with just a single bacterial cell over here. And this single bacterial cell will divide and replicate in order to create many more cells of the same exact species. And so we have a population of cells here, but this population of cells consists of just one single species. And because we have a lot of cells here, if we had about 1,000,000 cells or so, we would have ourselves a colony of cells or a group of cells that are all the same species. And so this is an example of a pure culture because it is a population of cells containing only one species. And so, notice here that this old guy over here saying, 'Look at all my children' and these guys are saying 'We form a colony together' and all cells are going to be descended from a single cell in a pure culture. That is what allows for the population of cells to only contain 1 single species. Now, there is another term here that might be important to keep in mind if you're in a microbiology lab and that is the term inoculum. And so an inoculum is really just a colony of cells that are added to a culture medium in order to start a pure culture. And so if we wanted to create a pure culture, what we would typically do is start with a colony of cells that are all of a single species, and then we would use that colony as an inoculum to inoculate growing a pure culture, and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.
- 1. Introduction to Microbiology3h 21m
- Introduction to Microbiology16m
- Introduction to Taxonomy26m
- Scientific Naming of Organisms9m
- Members of the Bacterial World10m
- Introduction to Bacteria9m
- Introduction to Archaea10m
- Introduction to Eukarya20m
- Acellular Infectious Agents: Viruses, Viroids & Prions19m
- Importance of Microorganisms20m
- Scientific Method27m
- Experimental DesignÂ30m
- 2. Disproving Spontaneous Generation1h 18m
- 3. Chemical Principles of Microbiology3h 38m
- 4. Water1h 28m
- 5. Molecules of Microbiology2h 23m
- 6. Cell Membrane & Transport3h 28m
- Cell Envelope & Biological Membranes12m
- Bacterial & Eukaryotic Cell Membranes8m
- Archaeal Cell Membranes18m
- Types of Membrane Proteins8m
- Concentration Gradients and Diffusion9m
- Introduction to Membrane Transport14m
- Passive vs. Active Transport13m
- Osmosis33m
- Simple and Facilitated Diffusion17m
- Active Transport30m
- ABC Transporters11m
- Group Translocation7m
- Types of Small Molecule Transport Review9m
- Endocytosis and Exocytosis15m
- 7. Prokaryotic Cell Structures & Functions5h 52m
- Prokaryotic & Eukaryotic Cells26m
- Binary Fission11m
- Generation Times16m
- Bacterial Cell Morphology & Arrangements35m
- Overview of Prokaryotic Cell Structure10m
- Introduction to Bacterial Cell Walls26m
- Gram-Positive Cell Walls11m
- Gram-Negative Cell Walls20m
- Gram-Positive vs. Gram-Negative Cell Walls11m
- The Glycocalyx: Capsules & Slime Layers12m
- Introduction to Biofilms6m
- Pili18m
- Fimbriae & Hami7m
- Introduction to Prokaryotic Flagella12m
- Prokaryotic Flagellar Structure18m
- Prokaryotic Flagellar Movement11m
- Proton Motive Force Drives Flagellar Motility5m
- Chemotaxis14m
- Review of Prokaryotic Surface Structures8m
- Prokaryotic Ribosomes16m
- Introduction to Bacterial Plasmids13m
- Cell Inclusions9m
- Endospores16m
- Sporulation5m
- Germination5m
- 8. Eukaryotic Cell Structures & Functions2h 18m
- 9. Microscopes2h 46m
- Introduction to Microscopes8m
- Magnification, Resolution, & Contrast10m
- Introduction to Light Microscopy5m
- Light Microscopy: Bright-Field Microscopes23m
- Light Microscopes that Increase Contrast16m
- Light Microscopes that Detect Fluorescence16m
- Electron Microscopes14m
- Reviewing the Different Types of Microscopes10m
- Introduction to Staining5m
- Simple Staining14m
- Differential Staining6m
- Other Types of Staining11m
- Reviewing the Types of Staining8m
- Gram Stain13m
- 10. Dynamics of Microbial Growth4h 36m
- Biofilms16m
- Growing a Pure Culture5m
- Microbial Growth Curves in a Closed System21m
- Temperature Requirements for Microbial Growth18m
- Oxygen Requirements for Microbial Growth22m
- pH Requirements for Microbial Growth8m
- Osmolarity Factors for Microbial Growth14m
- Reviewing the Environmental Factors of Microbial Growth12m
- Nutritional Factors of Microbial Growth30m
- Growth Factors4m
- Introduction to Cultivating Microbial Growth5m
- Types of Solid Culture Media4m
- Plating Methods16m
- Measuring Growth by Direct Cell Counts9m
- Measuring Growth by Plate Counts14m
- Measuring Growth by Membrane Filtration6m
- Measuring Growth by Biomass15m
- Introduction to the Types of Culture Media5m
- Chemically Defined Media3m
- Complex Media4m
- Selective Media5m
- Differential Media9m
- Reducing Media4m
- Enrichment Media7m
- Reviewing the Types of Culture Media8m
- 11. Controlling Microbial Growth4h 10m
- Introduction to Controlling Microbial Growth29m
- Selecting a Method to Control Microbial Growth44m
- Physical Methods to Control Microbial Growth49m
- Review of Physical Methods to Control Microbial Growth7m
- Chemical Methods to Control Microbial Growth16m
- Chemicals Used to Control Microbial Growth6m
- Liquid Chemicals: Alcohols, Aldehydes, & Biguanides15m
- Liquid Chemicals: Halogens12m
- Liquid Chemicals: Surface-Active Agents17m
- Other Types of Liquid Chemicals14m
- Chemical Gases: Ethylene Oxide, Ozone, & Formaldehyde13m
- Review of Chemicals Used to Control Microbial Growth11m
- Chemical Preservation of Perishable Products10m
- 12. Microbial Metabolism5h 16m
- Introduction to Energy15m
- Laws of Thermodynamics15m
- Chemical Reactions9m
- ATP20m
- Enzymes14m
- Enzyme Activation Energy9m
- Enzyme Binding Factors9m
- Enzyme Inhibition10m
- Introduction to Metabolism8m
- Negative & Positive Feedback7m
- Redox Reactions22m
- Introduction to Aerobic Cellular Respiration25m
- Types of Phosphorylation12m
- Glycolysis19m
- Entner-Doudoroff Pathway11m
- Pentose-Phosphate Pathway10m
- Pyruvate Oxidation8m
- Krebs Cycle16m
- Electron Transport Chain19m
- Chemiosmosis7m
- Review of Aerobic Cellular Respiration19m
- Fermentation & Anaerobic Respiration23m
- 13. Photosynthesis2h 31m
- 14. DNA Replication2h 25m
- 15. Central Dogma & Gene Regulation7h 14m
- Central Dogma7m
- Introduction to Transcription20m
- Steps of Transcription22m
- Transcription Termination in Prokaryotes7m
- Eukaryotic RNA Processing and Splicing20m
- Introduction to Types of RNA9m
- Genetic Code25m
- Introduction to Translation30m
- Steps of Translation23m
- Review of Transcription vs. Translation12m
- Prokaryotic Gene Expression21m
- Review of Prokaryotic vs. Eukaryotic Gene Expression13m
- Introduction to Regulation of Gene Expression13m
- Prokaryotic Gene Regulation via Operons27m
- The Lac Operon21m
- Glucose's Impact on Lac Operon25m
- The Trp Operon20m
- Review of the Lac Operon & Trp Operon11m
- Introduction to Eukaryotic Gene Regulation9m
- Eukaryotic Chromatin Modifications16m
- Eukaryotic Transcriptional Control22m
- Eukaryotic Post-Transcriptional Regulation28m
- Post-Translational Modification6m
- Eukaryotic Post-Translational Regulation13m
- 16. Microbial Genetics4h 44m
- Introduction to Microbial Genetics11m
- Introduction to Mutations20m
- Methods of Inducing Mutations15m
- Prototrophs vs. Auxotrophs13m
- Mutant Detection25m
- The Ames Test14m
- Introduction to DNA Repair5m
- DNA Repair Mechanisms37m
- Horizontal Gene Transfer18m
- Bacterial Transformation11m
- Transduction32m
- Introduction to Conjugation6m
- Conjugation: F Plasmids18m
- Conjugation: Hfr & F' Cells19m
- Genome Variability21m
- CRISPR CAS11m
- 17. Biotechnology3h 0m
- 18. Viruses, Viroids, & Prions4h 56m
- Introduction to Viruses20m
- Introduction to Bacteriophage Infections14m
- Bacteriophage: Lytic Phage Infections12m
- Bacteriophage: Lysogenic Phage Infections17m
- Bacteriophage: Filamentous Phage Infections8m
- Plaque Assays9m
- Introduction to Animal Virus Infections10m
- Animal Viruses: 1. Attachment to the Host Cell7m
- Animal Viruses: 2. Entry & Uncoating in the Host Cell19m
- Animal Viruses: 3. Synthesis & Replication22m
- Animal Viruses: DNA Virus Synthesis & Replication14m
- Animal Viruses: RNA Virus Synthesis & Replication22m
- Animal Viruses: Antigenic Drift vs. Antigenic Shift9m
- Animal Viruses: Reverse-Transcribing Virus Synthesis & Replication9m
- Animal Viruses: 4. Assembly Inside Host Cell8m
- Animal Viruses: 5. Release from Host Cell15m
- Acute vs. Persistent Viral Infections25m
- COVID-19 (SARS-CoV-2)14m
- Plant Viruses12m
- Viroids6m
- Prions13m
- 19. Innate Immunity7h 15m
- Introduction to Immunity8m
- Introduction to Innate Immunity17m
- Introduction to First-Line Defenses5m
- Physical Barriers in First-Line Defenses: Skin13m
- Physical Barriers in First-Line Defenses: Mucous Membrane9m
- First-Line Defenses: Chemical Barriers24m
- First-Line Defenses: Normal Microflora5m
- Introduction to Cells of the Immune System15m
- Cells of the Immune System: Granulocytes29m
- Cells of the Immune System: Agranulocytes25m
- Introduction to Cell Communication5m
- Cell Communication: Surface Receptors & Adhesion Molecules16m
- Cell Communication: Cytokines27m
- Pattern Recognition Receptors (PRRs)45m
- Introduction to the Complement System24m
- Activation Pathways of the Complement System23m
- Effects of the Complement System23m
- Review of the Complement System12m
- Phagoctytosis21m
- Introduction to Inflammation18m
- Steps of the Inflammatory Response26m
- Fever8m
- Interferon Response25m
- 20. Adaptive Immunity7h 14m
- Introduction to Adaptive Immunity32m
- Antigens12m
- Introduction to T Lymphocytes38m
- Major Histocompatibility Complex Molecules20m
- Activation of T Lymphocytes21m
- Functions of T Lymphocytes25m
- Review of Cytotoxic vs Helper T Cells13m
- Introduction to B Lymphocytes27m
- Antibodies14m
- Classes of Antibodies35m
- Outcomes of Antibody Binding to Antigen15m
- T Dependent & T Independent Antigens21m
- Clonal Selection20m
- Antibody Class Switching17m
- Affinity Maturation14m
- Primary and Secondary Response of Adaptive Immunity21m
- Immune Tolerance28m
- Regulatory T Cells10m
- Natural Killer Cells16m
- Review of Adaptive Immunity25m
- 21. Principles of Disease6h 57m
- Symbiotic Relationships12m
- The Human Microbiome46m
- Characteristics of Infectious Disease47m
- Stages of Infectious Disease Progression26m
- Koch's Postulates26m
- Molecular Koch's Postulates11m
- Bacterial Pathogenesis36m
- Introduction to Pathogenic Toxins6m
- Exotoxins Cause Damage to the Host40m
- Endotoxin Causes Damage to the Host13m
- Exotoxins vs. Endotoxin Review13m
- Immune Response Damage to the Host15m
- Introduction to Avoiding Host Defense Mechanisms8m
- 1) Hide Within Host Cells5m
- 2) Avoiding Phagocytosis31m
- 3) Surviving Inside Phagocytic Cells10m
- 4) Avoiding Complement System9m
- 5) Avoiding Antibodies25m
- Viruses Evade the Immune Response27m
Growing a Pure Culture - Online Tutor, Practice Problems & Exam Prep
In microbiology, a pure culture is a population of cells containing only one species, typically initiated from a single colony of approximately 1,000,000 cells. This process begins with an inoculum, which is a colony added to a culture medium to grow the pure culture. Understanding these concepts is crucial for studying bacterial and archaeal cells, as they allow for the isolation and examination of specific microorganisms in a controlled environment.
Growing a Pure Culture
Video transcript
A pure culture of bacteria is made of…
A bacterial culture grown in a _________________ will not continue to grow exponentially forever, but will stop once the limited nutrients have been consumed.
Do you want more practice?
Here’s what students ask on this topic:
What is a pure culture in microbiology?
A pure culture in microbiology is a population of cells that contains only one single species. This is typically achieved by starting with a single colony, which is a group of approximately 1,000,000 cells. The colony is used as an inoculum to inoculate a culture medium, allowing the cells to grow and replicate. The result is a controlled environment where only one species of microorganism is present, making it easier to study specific bacterial or archaeal cells without contamination from other species.
How is a pure culture initiated in a lab?
A pure culture is initiated in a lab by starting with a single colony of cells, which contains about 1,000,000 cells of the same species. This colony is used as an inoculum, which is added to a culture medium. The inoculum allows the cells to grow and replicate, forming a population of cells that all belong to the same species. This process ensures that the culture remains pure and uncontaminated by other microorganisms, facilitating accurate study and analysis.
What is an inoculum in the context of growing a pure culture?
An inoculum in the context of growing a pure culture is a colony of cells that is added to a culture medium to start the growth of a pure culture. The inoculum typically consists of about 1,000,000 cells of a single species. By using an inoculum, scientists can ensure that the resulting culture contains only one species of microorganism, which is crucial for accurate study and experimentation in microbiology.
Why is it important to use a pure culture in microbiology studies?
Using a pure culture in microbiology studies is important because it ensures that only one species of microorganism is present in the culture. This eliminates the risk of contamination from other species, allowing for more accurate and reliable results. Pure cultures are essential for studying the characteristics, behavior, and interactions of specific microorganisms, as well as for developing antibiotics and other treatments. They provide a controlled environment that is crucial for scientific research and experimentation.
What is a colony in microbiology?
In microbiology, a colony is a group of approximately 1,000,000 cells that originate from a single cell. Colonies are visible to the naked eye and are used to start pure cultures. Each colony consists of cells that are genetically identical, making them ideal for studying specific species of microorganisms. Colonies are essential for isolating and growing pure cultures, as they provide a starting point for the inoculum used in the culture medium.
Your Microbiology tutor
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- Match the following choices to the culture descriptions in questions 3 through 6:a. Chlamydiab. Coccidioidesc....
- “In the laboratory, a sterile inoculating loop is moved across the agar surface in a culture dish, thinning a ...