Which of the following is the correct order of the three main parts of a typical angiospermic leaf from the attachment point on the stem outwards?
A typical leaf is attached to the stem by the leaf base, followed by the stalk-like petiole, and terminates in the green expanded lamina.
Question 172 of 300
📘 CLASS XI
Identify the matching pairs of phyllotaxy type and their examples: 1. Alternate — China Rose 2. Opposite — Calotropis 3. Whorled — Alstonia
Which of these pairs are correct?
All three combinations are correct. Alternate phyllotaxy is found in China rose, mustard, and sunflower; opposite phyllotaxy is found in Calotropis and guava; whorled phyllotaxy is found in Alstonia.
Question 173 of 300
📘 CLASS XI
A plant species is found to have more than two leaves arising at a single node, forming a circular green cluster or ring. What is this phyllotaxy called, and which plant is a classic textbook example of it?
If more than two leaves arise at a node and form a whorl, it is called whorled phyllotaxy, with Alstonia as the standard textbook example.
Question 174 of 300
📘 CLASS XI
What is the developmental reason why a solitary flower is always produced when a shoot tip transforms into a flower?
When a shoot tip transforms into a flower, it is always solitary because the shoot apical meristem is entirely converted into the terminal floral meristem, ending further apical growth of that shoot axis.
Question 175 of 300
📘 CLASS XI
In a certain plant, the main floral axis continues to grow indefinitely and bears flowers laterally in an acropetal succession. What type of inflorescence is this?
In racemose inflorescences, the main axis continues to grow, and the flowers are borne laterally in an acropetal succession, with the oldest flowers at the base and the youngest near the tip.
Question 176 of 300
📘 CLASS XI
If you observe an inflorescence where the oldest flowers are located at the apex and the youngest flowers are located at the base (basipetal order), this inflorescence is:
In cymose inflorescences, the main axis terminates in a flower (the oldest), and subsequent flowers are produced on lateral branches below it, resulting in a basipetal order of development.
Question 177 of 300
📘 CLASS XI
Which of the following is a logical developmental consequence of suppressed internodal elongation during flower formation?
Suppression of internodal elongation condenses the floral axis (receptacle or thalamus). Consequently, the different floral appendages are produced at successive nodes close to each other, forming concentric floral whorls.
Question 178 of 300
📘 CLASS XI
Identify the incorrect match from the following options:
Racemose inflorescences feature flowers in acropetal succession, not basipetal. Basipetal flowers are characteristic of cymose inflorescences.
Question 179 of 300
📘 CLASS XI
When a stem apex transitions into a floral meristem, what change occurs in the pattern of lateral appendages produced?
When the shoot apical meristem transforms into a floral meristem, the axis condenses and the apex produces different kinds of floral appendages laterally at successive nodes instead of vegetative leaves.
Question 180 of 300
📘 CLASS XI
If a plant has a condensed floral axis where the terminal bud matures first into a flower, what is the fate of the growth of that axis?
This describes a cymose inflorescence, where the main axis terminates in a flower, which physically limits its further vertical growth.
