An Orthotropous Ovule is one in which the Micropyle and Chalaza are

Answer: An ovule is a structure in flowering plants where fertilisation occurs and seeds develop. It has important parts like:

• Micropyle – small opening for pollen tube entry
• Chalaza – base of the ovule
• Funiculus – stalk that attaches the ovule to the ovary wall
  

Depending on how these parts are arranged, ovules are classified as orthotropous, anatropous, hemitropous, campylotropous, or amphitropous. Now, let’s understand and analyse each option and find out the correct answer.

Option (A) In the straight line of a funiculus

In an orthotropous ovule, all major structures, funiculus, chalaza, nucellus, embryo sac, and micropyle, are arranged in one straight line. The ovule is upright and linear, without any curvature. This is a textbook example of the orthotropous arrangement and is the correct option.

Option (B) Parallel to the funiculus

If the micropyle and chalaza are parallel to the funiculus, it suggests that the ovule might be curved or bent alongside the stalk. This is seen in campylotropous ovules, where the ovule is curved, and its parts lie alongside but not in line with the funiculus. Therefore, this is incorrect for orthotropous ovules.

Option (C) At right angles to the funiculus

This describes hemitropous ovules, where the body of the ovule is positioned at a 90° angle to the funiculus. In this case, the micropyle and chalaza are not in a straight line but at an angle. Hence, this does not describe an orthotropous ovule and is wrong.

Option (D) Oblique to the funiculus

If the micropyle and chalaza are oblique (slanted) to the funiculus, it means they are angled, not straight or perpendicular. This occurs in amphitropous ovules, where the ovule is slightly twisted or curved in such a way that its axis becomes oblique. So, this is also incorrect.

Correct Answer: (A) In the straight line of a funiculus

Option A is correct because Orthotropous ovules are straight and upright. All parts, like micropyle, chalaza, and funiculus, are in a single vertical line. This arrangement is the simplest and most primitive form of ovule orientation. This is found in families like Polygonaceae (e.g., Polygonum).

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