1. The transfer of pollen grains from the anther of a stamen to the stigma of a carpel is called pollination. It takes place by various pollinating agents. Fertilisation occurs when the male gamete present in pollen grain joins with the female gamete (or egg) present in ovule. It takes place by naturalRead more

    The transfer of pollen grains from the anther of a stamen to the stigma of a carpel is called pollination. It takes place by various pollinating agents.

    Fertilisation occurs when the male gamete present in pollen grain joins with the female gamete (or egg) present in ovule. It takes place by natural or artificial means.

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  2. Insulin hormone regulates blood sugar levels. If this is not secreted in proper amounts, the sugar level in the blood rises. This causes many harmful effects. To treat harmful effects of increased level of blood sugar, the diabetic patients are treated by giving injections of insulin.

    Insulin hormone regulates blood sugar levels. If this is not secreted in proper amounts, the sugar level in the blood rises. This causes many harmful effects.
    To treat harmful effects of increased level of blood sugar, the diabetic patients are treated by giving injections of insulin.

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  3. The heart beat increases when adrenaline is secreted into the blood so that more oxygen is supplied to our muscles. The blood supply to the digestive system and skin decreases because the small arteries around the muscles of these organs contract. This turns the direction of blood towards our skeletRead more

    The heart beat increases when adrenaline is secreted into the blood so that more oxygen is supplied to our muscles. The blood supply to the digestive system and skin decreases because the small arteries around the muscles of these organs contract. This turns the direction of blood towards our skeletal muscles. The breathing rate also increases due to the contractions of the diaphragm and rib muscles. All these responses enable us to face the situations of fear and anger.

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  4. It is advised to use iodised salt because thyroid gland needs iodine to produce thyroxin hormone. Thyroxin hormone controls all the metabolic activities of our body like metabolism of carbohydrates, fats and protein etc. Due to the deficiency of thyroxin a disease called goitre is caused.

    It is advised to use iodised salt because thyroid gland needs iodine to produce thyroxin hormone. Thyroxin hormone controls all the metabolic activities of our body like metabolism of carbohydrates, fats and protein etc. Due to the deficiency of thyroxin a disease called goitre is caused.

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  5. Chemical coordination in animals takes place through the hormones secreted by the endocrine glands. Coordination in animals takes place through hormone system as well as nervous system which is called endocrine system. Endocrine glands secrete animal hormones directly into the blood that reach to thRead more

    Chemical coordination in animals takes place through the hormones secreted by the endocrine glands. Coordination in animals takes place through hormone system as well as nervous system which is called endocrine system. Endocrine glands secrete animal hormones directly into the blood that reach to the specific cells. Special type of molecules are present on the surface of cells to detect these hormones. These cells act according to the information that a particular hormone carries.

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