Test 1 Flashcards
What are 4 benefits of biotech methods?
- New and improved traits
- Faster production time
- Cheaper production cost
- Can be more eco-friendly
What’s a transgenic plant?
A plant that had a foreign gene or genes inserted into its DNA using genetic engineering techniques.
How could you engineer a transgenic plant?
Agrobacterium tumefaciens
Direct DNA transfer ex. Gene gun
What is micropropagation?
Method of plant propagation using extremely small pieces of plant tissue taken from a prepared mother plant, and growing these under lab conditions to produce new plants.
What is an explant?
An excised piece of differentiated tissue or organ that is used to initiate growth in culture.
How can we use Biotechnology to benefit agriculture?
Salinity tolerance
Pathogenic resistance
Improved nutrition (golden rice)
Reach max. Yield
Explain the steps for micropropagation.
- Choose plant material - explant
- Place on proper growth medium
- Plant tissue grows and differentiates into new tissues depending on the growth medium.
- Multiplication - a single explant may produce hundreds or thousands of plants.
- Pre-transplant - treat the plant-lets/shoots produced to encourage root growth in vitro.
- Remove plant-lets from media and transfer to soil.
What is endosperm?
Tissue found inside seeds that surround the embryo, inside the embryo sac. Usually contains starch with protein and other nutrients.
What is Nucellus?
Central part of the ovule, which contains the embryo sac.
What are some advantages of micropropagation?
- Inexpensive per plant once established
- Continuous propagation year-round
- Potential for disease-free propagules
- Rapid production of propagules
What are some disadvantages of micropropagation?
- More technical expertise required
- Specialized facility and equipment required
- Protocols not optimized for all species
- Relatively expensive to set up
What is acclimatization?
Process where plants functions and structures adjust from in vitro to ex vitro cultural and environmental conditions.
What are two reasons micro-propagated plants may be difficult to acclimatize ex vitro?
- Low photosynthetic competence
- Poor control of water loss (raised with high humidity)
What is Totipotency?
Plant cells retain the ability to change to a meristematic state and differentiate in to a whole plant if it has retained an intact membrane system and a viable nucleus.
What is in vitro and in vivo?
In vitro - research done in a lab dish or test tube.
In vivo - research done on a living organism.
Define friable callus and compact callus.
Friable - cells can be separated from each other easily to start new cultures.
Compact - cells are highly adherent to each other.
What is the xylem and the phloem?
Xylem - distributes water and dissolved minerals upward through the plant, from roots to leaves.
Phloem - transports food (sugars) downward from the leaves to the roots.
What is a big challenge of plant tissue culture? What can you do to overcome this challenge?
- Contamination
- Making sure to participate in aseptic techniques
Name important aspects of plant cell culture.
- Plant part of interest isolated from intact plant.
- Appropriate environment to promote optimal growth discovered and applied.
- Procedures must be carried out in a sterile environment to prevent growth of microorganisms.
Media requirements differ depending on what factors?
- plant species
- culture type (cells, callus, organ, tissue (epidermis, vascular, ground), protoplast)
- purpose and objective of experiment
What is callus?
A growing and dividing mass of cells that are undifferentiated and unorganized.
Hormones are added to promote differentiation.
Provide functions of media.
- provide water
- provide minerals and nutritional needs (ex. Carbon source)
- provide vitamins
- provide growth regulators
- access to atmosphere for gas exchange
- removal of plant metabolic waste.
Describe micro and macro elements.
Macroelements - elements required by plants in concentration GREATER than 0.5 mmol/L
Microelements - elements required in concentration LESS than 0.5 mmol/L
What is one example of a macroelement?
Nitrogen
What are 3 examples of microelements?
Iron
Zinc
Iodine
What is somatic embryogenesis?
Reproductive organs forming from plant cells not normally involved in the development of embryos.
What are the three stages of callus culture?
- Induction
- cells in explant dedifferentiate and begin to divide. - Proliferated stage
- rapid cell division - Differentiation stage (sometimes)
- organogenesis —> formation of organs.
What is the optimal pH for in vitro?
5.0 to 6.0
What is Auxin?
A plant hormone that causes the elongation of cells in shoots and is involved in regulating plant growth.
What are cytokinins?
A group of plant growth regulators which are primarily involved in performing cell division in plant roots, shoot system.
Antioxidant - browning preventer
List 5 media components.
- Media base
- Agar
- Carbohydrate source
- Antibiotics
- Growth regulators or other supplements.
Importance of callus culture.
- saves time and money to have a “stock” of cells to draw from.
- genetically modify callus cells then grow into whole plants.
