Why Plant Growth is Indeterminate (Open Form of Growth)
Biology · Plant Growth and Development · NEET
Plant growth is indeterminate because plants keep meristems (regions of dividing cells) active throughout their whole life, so new cells are always being added. This never-ending, unlimited type of growth is called the open form of growth. Memory hook: "Meristem = machine that never switches off, so growth never stops."
The meristem keeps dividing for life: one daughter cell renews the meristem while the other matures into the plant body, so new cells are always added. This is why plant growth is indeterminate (open form).
Your doubts, answered
Why exactly is plant growth called indeterminate?
Because there is no fixed final size. Plants keep special regions called meristems (at root tips, shoot tips, and in cambium) where cells divide again and again. Since new cells are added continuously as long as the plant lives, the growth has no fixed end point. This is the meaning of indeterminate.
What is the open form of growth?
NCERT defines it clearly: the form of growth in which new cells are always being added to the plant body by the activity of the meristem is called the open form of growth. "Open" means the growth is not closed off or finished. It is the same idea as indeterminate growth, just described from the meristem's side.
How is this different from animal growth?
In most animals, growth is determinate. They grow to a fixed adult size and then stop, because cell division mostly stops. In plants, meristems stay active for life, so plants can keep growing. This is why a tree can keep getting taller and wider for decades.
Which cells give plants this unlimited power?
Meristematic cells. NCERT says these cells have the capacity to divide and self-perpetuate (make more of themselves). One part of the product keeps dividing, while the other part loses the ability to divide and becomes the permanent plant body. This self-renewing pool is why growth never runs out.
Does the meristem ever stop dividing?
Usually it keeps dividing, which is why growth is indeterminate. But NCERT asks this on purpose: in some cases the meristem stops. For example, when a shoot apical meristem changes into a floral (flower) meristem, it stops adding stem and instead forms a flower. That part then shows a limited, determinate outcome.
⚠️ The NEET trap ✗ Choosing "Plant growth is generally determinate" as a correct statement, thinking plants also stop at a fixed size like animals. ✓ Plant growth is generally INDETERMINATE. Meristems give plants the capacity for unlimited (open) growth throughout life. So the statement "plant growth is generally determinate" is the INCORRECT one. 🧠 If the question asks which statement is NOT correct and "determinate" appears, that determinate line is usually the wrong statement they want you to catch.
Real NEET questions
NEET 2016-2023 (repeated)
Which of the following statements is not correct?
A · Plant growth is generally determinate. ✓
B · Plant growth is measurable.
C · Phase of cell elongation of plant cells is characterized by increased vacuolation.
D · Cells in the meristematic phase of growth exhibit abundant plasmodesmatal connections.
Solution: Plant growth is generally INDETERMINATE, not determinate, because meristems give plants the capacity for unlimited (open) growth throughout life. So statement (A) is not correct. The other three statements are all true. This exact question was repeated in NEET 2016, 2017, 2019, 2020, 2021 and 2023, so learn the NCERT line: "Plant Growth Generally is Indeterminate."
Solved Plant Growth and Development NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
In higher plants growth is generally indeterminate, meaning there is no fixed final size because meristems keep dividing throughout life.
Why is it called open form of growth?
Because new cells are always being added to the plant body by meristem activity, so growth stays "open" and never finished, as stated in NCERT Class 11 Chapter 13.
What makes unlimited growth possible in plants?
The presence of meristems whose cells can divide and self-perpetuate, keeping a permanent supply of dividing cells.
Can indeterminate growth ever become determinate?
Yes. When a shoot apical meristem turns into a floral meristem to make a flower, that meristem stops adding stem, so that part shows a determinate outcome.
Is this important for NEET?
Yes. The exact NCERT line about indeterminate growth has been asked directly in multiple NEET years, so it is high-yield and easy to score.
