Crop Plant Forms

CONTENT

• Flowering plant
• Parts of flowering plant
• The root system
• The shoot system.
• Functions of parts.

FLOWERING PLANT

Flowering plants or angiosperms are plants that produce flowers which have ovaries. Each ovary encloses young seeds called ovules. It is the ovary which later develops into a fruit while the ovules become mature seeds.Most of the plants we grow in our gardens or farms are called flowering plants.There are two divisions of flowering plants namely: monocotyledonous and dicotyledonous. The name cotyledon refers to the natural leaf borne by the seed of a plant.Cotyledon is otherwise known as seed leaf.

EVALUATION

1. What are flowering plants?
2. Give five examples of flowering plants.

PARTS OF FLOWERING PLANTS

A flowering plant whether monocot or dicot is made up of two major parties namely the root system and the shoot systems.

THE ROOT SYSTEM: The root system refers to the lower portion of the flowering plant which contains neither leaves nor reproductive organs. It develops underground and holds the whole plant firmly in the soil. The root system has many root hairs through which water, mineral salts and other nutrients enter the plant. In some crops, roots also store food. The root has at the apex a protective cap of tissue called the root cap. The root system contains one main or tap root side or lateral and root hairs. This type of root system is called a tap root system. For example in cowpea, pepper, orange, mango and guava. In other plants, all the roots are of almost the same length and thickness. These is no main root this is called fibrous  root system example include maize, rice, guinea corn and palm oil.

EVALUATION

1. List the parts that form the shoot system of a flowering plant.
2. Where is the root system found?

SHOOT SYSTEM

The shoot system of a flowering plant is differentiated into the stem, bud leaf, fruits, flower or inflorescence when the flower is fertilized, it develops into a fruit which contains the seed.

• STEM:It is the entire stand that carries the plant in place and it originates from that part of the embryo with the seed known as epicotyl.

• THE BUD: This is an embryonic on young shoot that has the capacity to produce leaves and branches. If a bud develops into branch bearing foliage leaves, it is called a leaf bud.

A flower bud is one which produces flower. A bud at the end of the shoot is called a terminal bud or apical bud. If in the axial of leaf, it is called axillary bud and from any other part of the shoot is adventitious bud.

• THE LEAF: the leaf arises as an exogenous outgrowth of the stem apex. It is from the side of the apex of a stem. As it progresses in its development, it grows outward from the leaf base, revealing the final shape and form characteristics of the species.

• THE FLOWER:The flower is a modified plant part specialized for reproduction and is responsible either directly or indirectly for bringing into existence new plants in order to perpetuate species.

THE SEED: a seed is a ripened ovule;it is the result of the changes which takes place in the ovule after fertilization.

• THE FRUIT: A fruit is a fully developed and ripened ovary or the result of the changes which go on in a flower due to fertilization.

EVALUATION

1. What is a flowering plant?
2. Give three examples of flowering plant.

FUNCTIONS OF PARTS OF FLOWERING PLANTS

FUNCTIONS OF THE ROOT

1. The root fixes the plant in the soil.
2. The root absorbs water and mineral salts from the soil for the use of the plant.
3. Sometimes, roots also function as storage organs as in the case of the cassava.
4. In an uncultivated land, the root system enriches the surface layer of the soil with the nutrients necessary for the plant growth.
5. The roots of some plants are used in preparation of drugs.
6. The roots of some plants such as carrot are used as food.
7. Roots also prevent soil erosion.
8. Roots are used in vegetative propagation, for example in sweet potato.

EVALUATION

1. Outline five functions of root.
   1. State two types of roots

FUNCTIONS OF STEM

1. The stem conducts material to and from the leaves.
2. Itsupports the leaves and distribute them in space so that they receive adequate light.
3. The stem also stores food as in the case of sugar cane.
4. It is used as cutting for propagation as in cassava, bitter leaf etc.
5. Woody stem supplies timber, for building etc.
6. Some stems, such as bamboo stem and the thick are used as poles.
7. The barks of some stem are used for medicinal purposes.
8. It supports the flowers. It exposes them for pollination.

EVALUATION

1. Mention three functions of the stem.
   1. State two economic importance of stem

FUNCTIONS OF LEAF

1. The leaf is the main seat of photosynthesis.
2. The leaf carries out transpiration an activity which ensures absorption from the soil and this helps to control transportation in plants.
3. It serves as food in form of vegetables which can give vitamins and mineral to the body.
4. Dead leaves serves as manure to the soil.
5. Leaves are also used as drug.

EVALUATION

1. State the functions of leaves.
2. State the functions of stems.

FUNCTIONS OF FLOWER

1. It produces of seeds for the perpetuation of the species.
2. It is used for decorative purposes.
3. It is also used for natural dyestuffs.

FUNCTION OF BUD

It produces the leaves, branches and flowers.

FUNCTIONS OF SEED

1. The seed serves for reproduction.
2. The seed serves for food.

FUNCTIONS OF FRUIT

1. It is an agent for seed disposal and survival.
2. It serves as food to man.

GENERAL EVALUATION AND REVISION QUESTIONS

1. State the functions of flowers.
2. State the functions of seed.
3. List three parts of flowering plants.
4. List three parts of a leaf.
5. What is Horticulture?

READING ASSIGNMENT

Junior Secondary Agriculture for Nigerian Schools by A. Yondeowei Bk. 1. Chapter 3, pages 20-25.

WEEKEND ASSIGNMENT

1. The distance between two nodes on a plant is called____________ A. bud B. internodes C. radicle D. apex.
   • The shoot system in a plant consists of the following except A. stem B. leaf  C. root D. flower
2.   The other name for a “main root” is____ A. tap root B. lateral C. adventitious D. fibrous.
3. A fully developed and ripened ovary is called ____A. fruit B. seed C. flower D. bud.
4.   A ripened ovule is otherwise known as ____A. seed. B. fruit C. flower D. bud.

THEORY

1. Name the parts that form the root system of a named plant.
2. Name the part that forms the shoot system of a named plant.