Plant Biotech (Intro to PTCs)

Question 1

What IS PTC (oso known as micropropagation)

Answer 1

Culture of plant cells, tissue and organs in nutrient medium in an aseptic + controlled environment

Used to regenerate plantlets

Question 2

What is cell totipotency

Answer 2

The ability of single cells to undifferentiate and produce diff cells that form plant organs a regenerate into a whole plant

totipotency -> ability to regenerate a whole organism from a single cell

Question 3

Types of morphogenesis?

Answer 3

Organogenesis: form shoots, roots, leaf (not entire plant)
Somatic embryogenesis:
somatic refering to body cells (non-reproductive cells)

Question 4

Types of Organogenesis?

Answer 4

Direct:
Explant -> put on culture to grow -> transfer culture to grow roots -> become entire plant
(used if not needed to mass produce)

Indirect:
Take explant -> culture to make callus -> transfer callus to culture to grow shoots / roots -> grow entire plant
(used if needed to mass produce)

Question 5

What is somatic embryogenesis?
What are the types of somatic embryogenesis?

Answer 5

The process where somatic cells undergo differentiation to form a bipolar structure (root and shoot)

Direct: Explant -> induce to grow embryo

Indirect: Explant -> callus -> induce to grow embryo

Question 6

What are there 4 stages of somatic embryos

Answer 6

Globular -> heart -> torpedo -> cotyledonary

mutations r common when using somatic embryos and may not result in identical plants

Question 7

Types of PTCs?

(refer to slides for more details)

Answer 7

Leaf: Using pieces of leaf and cultured in vitro to grow plantlets (younger leaves have higher success rate of propagation)

Stem: Using pieces of stem and cultured in vitro to grow plantlets

Embryo: Embryo from plant is grown in vitro in nutrient medium (used to make hybrid plants)

Callus (mass of undifferentiated cells) : used for mass production. Induced in lab to differentiate and form shoots / roots with plant growth regulators (PGRs)

Cell suspension culture: Take callus and put in liquid medium and shake it to separate into single cells. Can use this culture to grow plant cells

Question 8

Applications of PTCs?

Answer 8

1. Produce exact copies of plants that have desirable characteristics
2. Conserve rare / endangered species
3. mass production of mature plants w/o pollinators / seeds
4. regenerate whole plants from plant cells that are genetically modified