61.Ethylene is a growth ———-

1. retardant
2. Inhibitor
3. Increase
4. All

62.——- is also a growth retardant which induces stomata closing, also involved inhibition of bud growth and shoot formation

1. Ethylene
2. Abscissic acid
3. Auxins
4. Gibberellin

7. Sterile Techniques

63.————- techniques are used to clean equipment and for surface sterilization of explants.

1. Disinfectant
2. Sterile
3. Both a and b
4. None of these

64.. The ————- filters air with a dust filter and a high-efficiency particulate air (HEPA) filter.

1. laminar flow hood
2. Sterlize Techniques
3. Disinfectant
4. All

65.. It is important to keep the hood clean, which can be done by wiping it with —- alcohol.

1. 100%
2. 95%
3. 70%
4. 10%

66. Hands should be ————— with ethanol before handling cultures in order to avoid    contamination.

1. disinfected
2. Sterlize
3. Both
4. None of These

67.Humidity, light, and temperature have to be controlled for proper growth of cultures

1. Humidity
2. light
3. temperature
4. All

68.A 16-h light photoperiod is optimal for tissue cultures, and a temperature of——– is used in most laboratories

1. 30-200C
2. 22–258C
3. 22-400C
4. 10-800C

69.A light intensity of 25–50mmol.m-2s -1 PAR (photo synthetically active radiation) is typical for tissue cultures and is supplied by cool —- fluorescent lamps.

1. Green
2. Red
3. white
4. Blue

70.A relative humidity of ——— is maintained in the growth chambers

1. 10-20%
2. 20-30%
3. 100-110%
4. 50– 60%