CELL DIVISION
CELL DIVISION AND CANCEROUS CELLS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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An increase in growth hormone
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A decrease in growth hormone
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Death of nearby cells
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Decrease in surface area to volume ratio
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Detailed explanation-1: -The action of growth hormone-releasing hormone on the pituitary gland is counteracted by somatostatin, a hormone also produced by the hypothalamus, which prevents growth hormone release.
Detailed explanation-2: -Abscisic acid is a hormone which inhibits growth. Its effects include wilting of leaves, seed dormancy, etc. Hence it is not associated with the growth of plants. Auxin, gibberellins and cytokinins are plant hormones associated with the growth of plants.
Detailed explanation-3: -Insulin-like Growth Factor I (IGF-I) inhibits GH secretion by a negative loop at both hypothalamic and pituitary levels. In addition, age, gender, pubertal status, food, exercise, fasting, sleep and body composition play important regulatory roles.
Detailed explanation-4: -Growth hormone levels are increased by sleep, stress, exercise and low glucose levels in the blood. They also increase around the time of puberty. Growth hormone release is lowered in pregnancy and if the brain senses high levels of growth hormone or insulin-like growth factors already in the blood.