Grade: 6th class Time: 45 min. Topic: Plant Body Structure
Plant Organs__________________________________________
Vegetative Organs Reproductive Organs
Root, Stem, Leaf Seed, Flower, Fruits
ROOTS: They absorb water and minerals from the soil. They also store foods in some plants. Such as; carrot, beet
They have no chloroplasts. A root contains Root Hairs, Epidermis, Apical Meristem, Root Cap, Xylem, Phloem
Root Hairs: these are very tiny structures. They provide increasing the surface area in soil( for absorbing water and minerals)
Epidermis: It covers the root. It provides protection
Apical meristem: It provides the longitudinal growth of roots.
Root Cap: It protects the apical Meristem cells.
Xylem: located at the center of the root. It provides absorbing/transporting water and minerals
Phloem: located at the center of the root. It provides absorbing/transporting organic nutrients. Such as; glucose
STEM: It provides connection btw roots and leaves. They have nodes. There are 2 types of stem.
Woody Stem 2) Herbaceous Stem
It contains thick wood. It is soft and green
It is non-photosynthetic It is photosynthetic
Plants with woody stems can live more than 2 years Plants with herbaceous stems can live either 1 or 2 years
For example: pine or oak trees for example: cactus
LEAVES: Their shape and size are different. Function; photosynthesis, gas exchange, transpiration, regulation of temperature, excretion (excess water is removed as water vapors)
A leaf contains; The Cuticle, Epidermis, The Mesophyll , The Vascular bundles(veins)
The Cuticle Layer: It covers the outer surface of leaf. It provides preventing water loss from the leaf surface. There are lots of Stomata(pores). They provide exchanging of gases. (It doesn’t let passing O2 and CO2 through it).
Epidermis: It provides protection of internal tissues from mechanical damages and bacterial or fungal invasion.
The Mesophyll Layer: It contains many chloroplasts. It is responsible for Photosynthesis.
The Vascular bundles (veins): It is responsible for transporting materials. It contains Xylem and Phloem.
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