SCIENCE

=media type="youtube" key="uj0DFDfQajw" height="344" width="425"media type="youtube" key="-P4N-0Wbtyk" height="344" width="425"[SVyEpeniCzQ]media type="youtube" key="n0plgHU-BCo" height="344" width="425"Homework :media type="youtube" key="SVyEpeniCzQ" height="344" width="425"= Animal and plant nutrients:Phenomenal progress has been made in our understanding of the several and diverse ways in which micronutrients alter or regulate the functioning of plants and produce a wide array of responses enabling quantitative and qualitative changes in plant yield.**.** **General** Micronutrients as Essential Plant Nutrients; Micronutrients and the Periodic Table; General Functions of Micronutrients


 * .** **Iron**


 * .** **Manganese**


 * .** **Copper**


 * .** **Zinc**


 * .** **Molybdenum**


 * .** **Boron**

= = A primary function of boron is related to cell wall formation, so boron-deficient plants may be stunted. Sugar transport in plants, flower retention and pollen formation and germination also are affected by boron. Seed and grain production are reduced with low boron supply.  Copper is necessary for carbohydrate and nitrogen metabolism and, inadequate copper results in stunting of plants. Copper also is required for lignin synthesis which is needed for cell wall strength and prevention of wilting. Deficiency symptoms of copper are dieback of stems and twigs, yellowing of leaves, stunted growth and pale green leaves that wither easily.  Iron is involved in the production of chlorophyll, and iron chlorosis is easily recognized on iron-sensitive crops growing on calcareous soils. Iron also is a component of many enzymes associated with energy transfer, nitrogen reduction and fixation, and lignin formation. Iron is associated with sulfur in plants to form compounds that catalyze other reactions.  Manganese is necessary in photosynthesis, nitrogen metabolism and to form other compounds required for plant metabolism. Interveinal chlorosis is a characteristic manganese-deficiency symptom. In very severe manganese cases, brown necrotic spots appear on leaves, resulting in premature leaf drop.  Molybdenum is involved in enzyme systems relating to nitrogen fixation by bacteria growing symbiotically with legumes. Nitrogen metabolism, protein synthesis and sulfur metabolism are also affected by molybdenum. Molybdenum has a significant effect on pollen formation, so fruit and grain formation are affected in molybdenum-deficient plants. Because molybdenum requirements are so low, most plant species do not exhibit molybdenum-deficiency symptoms  Zinc is an essential component of various enzyme systems for energy production, protein synthesis, and growth regulation. Zinc deficient plants also exhibit delayed maturity. Zinc is not mobile in plants so zinc-deficiency symptoms occur mainly in new growth. Poor mobility in plants suggests the need for a constant supply of available zinc for optimum growth. The most visible zinc deficiency symptoms are short internodes and a decrease in leaf size. Delayed maturity also is a symptom of zinc-deficient plants.  Because chloride is a mobile anion in plants, most of its functions relate to salt effects (stomatal opening) and electrical charge balance in physiological functions in plants. Chloride also indirectly affects plant growth by stomatal regulation of water loss. Wilting and restricted, highly branched root systems are the main chloride-deficiency symptoms, which are found mainly in cereal crops. Most soils contain sufficient levels of chloride for adequate plant nutrition.
 * .** **Chlorine**

Term III Invertebrates Animals Reproduction :

Octopus: . The reproduction of the octopus :is the ale have a special arm that in there have a organ called hectocotylus, this organ insert in the spermatophores of the female .Then a few months the male die and the female is alone. Then the female have eggs, The female can have 20 000 eggs. The female have to protect the eggs for the predators, and gently blowing currents of water over them so that they get enough oxygen. In this period the octopus don`t eat and die after when the roughly. The baby octopus have found his food .This is the reproductio of the octopus.



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