Biology · Plant Growth and Development · NEET
Yes. In NCERT, geometric growth is described as growth that increases at an exponential rate during the log phase. So the words geometric and exponential are used for the same pattern here. The growth is slow at first (lag phase), then very fast (exponential/log phase), then slows down (stationary phase).
After a mitotic cell division, geometric growth is the case where both progeny (daughter) cells keep the ability to divide and continue dividing. This is the key difference from arithmetic growth, where only one daughter cell divides and the other matures. Because both cells divide, the number of dividing cells keeps doubling, so growth speeds up.
It is the formula for exponential (geometric) growth. W1 = final size (weight, height or number), W0 = initial size at the start, r = growth rate, t = time of growth, and e = base of natural logarithms. It tells you the final size depends on the initial size W0 and the growth rate r.
No. Arithmetic growth gives a straight line (linear). Geometric growth gives a curve that rises slowly, then shoots up steeply. When resources become limited it flattens, so the full geometric growth of a plant gives a sigmoid (S-shaped) curve.
No. In real plants nutrients and space are limited. So the fast exponential rise cannot go on forever. Growth slows down and reaches a stationary phase. This is why geometric growth in nature produces an S-shaped (sigmoid) curve, not an endless upward line.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Growth in which both daughter cells formed after mitosis continue to divide, giving an exponential (rapid) increase in size or number.
W1 = W0 e^rt, where W1 = final size, W0 = initial size, r = growth rate, t = time, and e = base of natural logarithms.
r is the growth rate. It is called the relative growth rate and is a measure of the plant's ability to produce new plant material, also known as the efficiency index.
Because resources become limited, geometric growth in a plant gives a sigmoid (S-shaped) curve with a lag phase, a fast log/exponential phase, and a stationary phase.
In arithmetic growth only one daughter cell divides (constant, linear rate). In geometric growth both daughter cells divide, so the rate keeps increasing (exponential).
