71.
Which of the following seems the most appropriate energy level responsible for electron transfer in the reduction of a chemical acceptor and the initiation of the electron flow for ATP production?

75.
When an organ grows at an intermediate angle i.e. between 0° to 90° or between 90° to 180° from the vertical, it is said to be

76.
The seeds of certain plants fail to germinate, if they do not pass through the digestive tract of fruit-eating birds. This is due to

77.
Consider the following statements regarding recurrent type apomixis and choose the correct answer:
1. There is meiosis during the formation of megaspore
2. The embryo sac is diploid in nature
3. The embryo sac never develops from a cell of the archesporium
4. The development of embryo from a cell of an embryo sac other than egg is known as apospory

79.
Consider the following statements and choose the correct answer:
1. The immediate precursor of gibberellin is the diterpene kaurene
2. The gibberellins are compounds consisting of the ent-gibberellane skeleton or ent-20 norgibberellane
3.The gibberellins are easily inter-convertible in the organism by changes in the hydroxyl substitutions

80.
Total soil-moisture stress represents