Short Answer TypeDifferentiate between :
(i) Reparative and Restorative regeneration.
(ii) Capacitation and fertilization.
Give one difference between:
(i) Intraspecific struggle and Interspecific struggle.
(ii) Somatogenic variation and Blastogenic variation.
Long Answer Type(a) Give the anatomical differences between a dicot leaf and a monocot leaf.
(b) Enlist the functions of mineral elements in the life of a plant. What do you mean by essentiality of an element ?
(c) Write the differences between nastic and tropic responses.
| Dicot leaf | Monocot leaf |
| Dorsiventral leaf | Isobilateral leaf |
| Stomata more on the lower surface of the leaf | Stomata equally distributed. |
| Bulliform cells are present in the epidermis. | Bulliform cells are absent in the epidermis |
| Mesophyll is not differentiated into palisade and spongy parenchyma | Mesophyll is differentiated into palisade and spongy parenchyma |
Nitrogen: It is an integral part of amino acids, proteins vitamins, coenzyme, nucleotide, alkaloids and chlorophyll.
Phosphorus : It is a constituent of cell membrane nucleic acids and nucleotide, certain coenzyme and A.T.P influences nitrogen metabolism used in the phosphorylation of sugar in respiration.
Potassium : It helps to maintain the electrical, osmotic and anion/cation balance across cell membranes, assists active transport of certain materials. It also helps in protein synthesis and is a cofactor of enzymes found in photosynthesis and respiration; it is a constituent of sap vacuoles in plants and so help to maintain turgidity.
Sulphur : A constituent of coenzyme A, Ferredoxin, Vitamins and amino acids.
Magnessium : A constituent of chlorophyll molecules; an activator for many enzyme helps in photosynthesis and Carbohydrate metabolism.
Calcium : A major component of the middle lamella of cell walls and it is necessary for their proper development, aid the translocation of carbohydrate and amino acid.
Iron : It is a constituent of electron carriers e.g. cytochoromes needed in respiration and photosynthesis and a constituent of enzymes e.g. dehydrogenase.
Micronutrients:
Chlorine : Helps to maintain the electrical, osmotic and anion/cation balance across cell membranes.
Manganese : It activates enzyme involved in fatty acid synthesis.
Boron : Helps in the mobilization of nutrients, cellular differentiation development.
Zinc : It is involved in biosynthesis of IAA, activates enzymes like carboxylases.
Copper : It is an essential part of plastocyanin.
Molybdenum : Nitrogen fixation & Nitrogen metabolism.
The Essentiality of a mineral element
(1) The element must be absolutely essential for normal growth and development of the plant.
(2) The requirement of the element must be specific and it can not be replaced by another element.
(3) The element must be directly involved in the nutrition of the plant, is the part of structural molecules.
(c)| Nastic movements | Tropic movements |
| Nastic responses are also growth movement which occur in response to external stimuli but here the movement is unrelated and the direction of the stimulus is not fixed, it is diffused. | Tropic Response: are the growth movement which occur in response to unidirectional external stimuli and result in positioning of the plant part in the direction of stimulus. |
| For example geotropism, seismonasty | For example - Geotropism, phototropism. |
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