4. ROOT Root is a non-green, underground, descending portion of the plant axis Develops from radicle
5.
6. Characteristics of root Descending part Negatively phototrophic Non-green Root cap /root pockets Unicellular root hair No nodes Lateral roots Endogenously
7. Regions of typical root Root cap – mucigel to lubricate Zone of cell division Zone of elongation Zone of root hair or absorption Zone of maturation or differentiation
8. Functions of root Anchorage Absorption Conduction of water & minerals Transport of nutrients
9. Types of root system Tap root system Roots develops, usually from the radicle of an embryo of seed is called tap root & the system is called tap root system. 2. Fibrous Root System The roots which develop from any other part of the plant except the radicle is called adventitious root and this system is called adventitious or fibrous root system. eg. Monocot plants
29. BUDS Apical bud Axillary Bud Mixed Buds Produce both vegetative & floral branches Borne at the apex of main branch Occur in theaxis of leaf
30. Modifications of stem The structural and functional change in the normal form and structure of the stem due to change in normal function of the stem is called modification of the stem
64. Phylloclade with one or two internodes Cladode Asparagus needle like, slightly flattened, green, appear in clusters in the axil of a scaly leaf Ruscus looks like leaf. Develops from axil of a scaly leaf. Bearing floral bud Asparagus
76. Leaf Parts The cuticle is part of the epidermis It produces a waxy layer called cutin, which protects the leaf from dehydration and disease. On the top and bottom is a layer of thick, tough cells called the epidermis. Its primary function is to protect the other layers of leaf tissue.
77. Leaf Parts Continued Special epidermal cells called guard cells open and close in response to environmental stimuli, such as changes in weather and light. They regulate the passage of water, oxygen, and carbon dioxide into and out of the leaf through tiny openings called stomata. Located between the upper and lower epidermis is the mesophyll. Located within the mesophyll cells are chloroplasts, where photosynthesis takes place.
