1 Plant Tissue Culture

Question 1

What is plant tissue culture?

Answer 1

The growth or regeneration of plant cells, tissues, organs or whole plants in artificial medium under aseptic conditions

Question 2

First commercial use of plant tissue culture on artificial media

Answer 2

Germination and growth of orchid plants, in the 1920’s

Question 3

Which medium was developed in 1962 that made plant tissue culture “take off” comercially?

Answer 3

Murashige & Skoog

Question 4

What is totipotency?

Answer 4

The ability of a cell to differentiate and develop into a whole plant when given the correct conditions, every plant cell has the genetic potential of the parent plant

Question 5

True or false : an explant can be any portion of the plant: shoot, leaves, roots, flower or cells

Answer 5

True

Question 6

What is an explant?

Answer 6

Living tissue transferred from a plant to an artificial medium for culture.

Question 7

What is micropropagation?

Answer 7

The production of whole plants from small sections of a plant, called an “explant”, a whole plant is produced, which is genetically identical to the mother plant

Question 8

What is the difference between ex vivo and in vivo?

Answer 8

Ex vivo refers to something being investigated upon, outside its natural environment (in an artificial environment) and in vivo studying something at its natural environment

Question 9

Stem cells in plants are called:

Answer 9

Meristems

Question 10

Undefferentiated cells are:

Answer 10

biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells

Question 11

Why do plants need differentiation?

Answer 11

to go through a series of morphological and physiological changes to become specialized for a particular function

Question 12

What is callus ?

Answer 12

undifferentiated cell mass

Question 13

What is de-differentiation?

Answer 13

Plants that have differentiated cells or tissues are gradually restored to the meristematic state in vitro under culture conditions, there is a disappearance of special cell morphology and function and usually results in the formation of callus

Question 14

What is re-differentiation?

Answer 14

In vitro, after cell de-differentiation, the disorderly growing cells (callus) re-enter the process of orderly growth or differentiation

Question 15

Why is subculture necessary?

Answer 15

it becomes necessary, due to nutrient depletion and medium drying, to transfer organs and tissues to fresh media.

Question 16

Types of tissue culture:

Answer 16

1 Organized: culture of whole or parts of a plant. The characteristics and organizational structure of a plant or organ is maintained.
2 Unorganized: callus culture, cell suspension culture

Question 17

Tissue culture techniques examples:

Answer 17

Micrografting :to eliminate viruses

In vitro pollination and fertilization: Used by plant breeders to create new varieties

Question 18

Avantages of plant tissue culture

Answer 18

Mass production of various plant cultivars, Production of pathogen-free plants, germplasm preservation, Continuous year round production, The original plant is not destroyed in the process and propagated in controlled lab conditions

Question 19

Disadvantages of plant tissue culture

Answer 19

Specialized equipment required, High labor cost is the most limiting factor, Contamination or mutations risks,

Question 20

Factors affecting tissue culture

Answer 20

The genetic make-up of the plant
Source of explants
Nutrients
Environmental factors:
Light, Temp, pH, O2 & CO2 concentrations

Question 21

Plant culture conditions

Answer 21

25 ±1°C
Photoperiod = 12-16h
1000-5000 lux
Quality fluorescent lamps and/or LEDs
Controlled Humidity