Q11Written answer
In the figure of Sigmoid growth curve given below, label segments 1, 2 and 3.
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Ans: (1) Lag phase, (2) Exponential phase and (3) Stationary phase
NCERT Exemplar · Class 11 · Biology
Chapter 15: Plant Growth and Development
Practice each question, then open the answer or worked solution.
Very Short Answer Questions
13 questionsQ12Written answer
Growth is one of the characteristic of all living organisms? Do unicellular organisms also grow? If so, what are the parameters?
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Ans: Unlike multicellular organisms, unicellular organisms do not grow in size or volume. Growth in unicellular organisms is marked by mitosis which produces daughter cells. Thus, asexual reproduction by amitosis shows growth in these organisms.
Q13Written answer
The rice seedlings infected with fungus Gibberella fujikuroi is called foolish seedlings? What was the reason behind it?
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Ans: Rice plants which got infected with the fungus Gibberella fujikuroi grow excessively long. The plant's length becomes too great for it to sustain its own weight, and it eventually dies. As a result, this phenomena is known as stupid seedlings.