04 Cell Culture and Aseptic Technique Free Online FlashCards

What does aseptic technique aim to do?

Aseptic technique uses practices that reduce the chance of contamination; it does not guarantee a completely sterile workspace.

What can contaminate a culture, and why does it matter?

Contaminants can come from people, air, surfaces, tools, reagents, or other cultures, and can alter results or destroy a culture.

Which practices help reduce contamination during culture handling?

Prepare an organized work area, use sterile supplies, open vessels only when needed, keep them closed otherwise, and avoid contact between sterile items and nonsterile surfaces.

Why must culture media be prepared and stored aseptically?

Contamination in a medium can spread to every culture that receives it, so aseptic preparation and storage are important.

How do general-purpose and enriched microbial media differ?

A general-purpose medium supports many organisms; an enriched medium adds nutrients for organisms with more demanding requirements.

What distinguishes selective media from differential media?

Selective media inhibit some organisms while favoring others. Differential media reveal visible differences in growth or substance use, often with a color indicator.

What components commonly support plant tissue cultures?

Plant media commonly provide mineral nutrients, vitamins, a sugar source, and plant growth regulators.

How can auxins and cytokinins affect plant tissue cultures?

The balance of auxins and cytokinins can influence whether cultured plant tissue forms callus, shoots, or roots.

What is the role of Murashige and Skoog (MS) medium?

Murashige and Skoog (MS) medium is a widely used starting formulation, but the best recipe depends on the species, tissue, and growth stage.

What does animal-cell culture medium generally provide?

Animal-cell basal media generally contain salts, amino acids, vitamins, and an energy source. Depending on the cell type, serum or defined supplements may also be needed.

How can animal-cell media maintain a suitable pH?

Buffering helps maintain a suitable pH; some systems use bicarbonate together with a controlled carbon-dioxide atmosphere.

What growth phases commonly occur in a closed batch culture?

In a closed batch culture, nutrients are gradually used and waste accumulates; growth commonly passes through lag, exponential, stationary, and decline phases.