Differentiate between:- Hypocotyl and epicotyl;
- Coleoptile and coleorrhiza;
- Integument and testa;
- Perisperm and pericarp
- Hypocotyl and epicotyl;
- Coleoptile and coleorrhiza;
- Integument and testa;
- Perisperm and pericarp
Solution and Explanation
Differentiate between
(a)
| Hypocotyl | Epicotyl | |
| 1. | The portion of the embryonal axis which lies below the cotyledon in a dicot embryo is known as the hypocotyl. | The portion of the embryonal axis which lies above the cotyledon in a dicot embryo is known as the epicotyl. |
| 2. | It terminates with the radicle. | It terminates with the plumule. |
(b)
| Coleoptile | Coleorrhiza | |
| It is a conical protective sheath that encloses the plumule in a monocot seed. | It is an undifferentiated sheath that encloses the radicle and the root cap in a monocot seed. | |
(c)
| Integument | Testa | |
| It is the outermost covering of an ovule. It provides protection to it. | It is the outermost covering of a seed. | |
(d)
| Perisperm | Pericarp | |
| It is the residual nucellus which persists. It is present in some seeds such as beet and black pepper. | It is the ripened wall of a fruit, which develops from the wall of an ovary | |
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Concepts Used:
Post-Fertilization Events
There are series of events that happen in the development of plants after their fertilization process to form a fruit from a diploid zygote. The four different developmental steps that occurs during post fertilization are:
- Development of an Endosperm: The endosperm, a tissue, present in the seed during the fertilization, precedes the development of an embryo. It is categorized into three types.
- Nuclear Formation
- Cellular Formation
- Helobial Formation
- Development of an Embryo: Embryogeny is the embryo development process and it starts developing at the micropylar end of the embryo sac in the zygote. The formation stages of embryogeny are almost the same in both the plants dicot and monocot, regardless of their structure.
- Monocot Embryo
- Dicot Embryo
- Development of a Seed: A Seed has Three Body Parts:
- Seed Coat
- Cotyledon
- Embryo Axis
- Formation of a Fruit: After the cell division and separation in the ovary, it is changed into fruit because of stimuli received from fertilization just as developing seed. The pericarp which might be fleshy like guava, tomato, or cucumber or might be weathered and dry like pea, bean, or mustard. After all the events the two types of fruits are formed:
- True Fruit
- False Fruit