NEET Biology Notes Neural control and chemical coordination Hormonal Disorders
If hormone imbalance is left untreated it can result in serious medical conditions like diabetes. If the inbalance is taking place in the pituitary glands, growth disorders are possible and will require treatment of a growth hormone. ,
Some of the diseases due to the hormonal disorders are given below :
It is the condition of having smaller body size (1-1.3 m) due to premature stoppage of body growth and reduced development of skeleton mainly because of under secretion of growth hormones from the beginning. In dwarfism, intelligence and altertness are normal.
It is the condition of abnormal growth of hands, feet and face especially lower jaw due to the over secretion of growth hormone in an adult. The appearance may be gorilla-like.
It is characterised by dwarfism, physical and mental deficiencies or under-development with a peculiar infantile facial expression scanty hair, pug nose, low body temperature, low heart rate, low blood pressure, pot belly, swollen eye lids, etc. It is due to less secretion (hypothyroidism) of thyroid hormones.
It mainly occurs due to the iodine deficiency, leading to enlargement of thyroid glands. It occurs in certain pockets in Northern hilly areas, where soil and ground water is deficient in iodine.
- Exophthalmic Goitre/Grave’s Disease
It is due to the hyperthyroidism or thyrotoxicosis, which is caused by autoimmune disorder in which antibodies are produced which mimic TSH. Due to this, feed back system fails and thyroxine is oversecreted. Thyroid glands swell up, oedema occurs behind the eyes, resulting in protrusion of eyes or exophthalmia. The other traits are high BMR, increased appetite accompanied by leanness, increased heartbeat, excessive sweating, dizziness, nervousness, etc.
The disorder is caused by less insulin secretion by pancreas. Diabetes is characterised by hyperglycaemia (high glucose levels); glucose in urine; excessive urination; excessive thirst; dehydration; acidosis; healing power is reduced; blurred vision, may lead to coma or unconsciousness.
- Addison’s Disease
It usually results due to destruction of adrenal cortex or deficient secretion of aldosterone and cortisol. There is electrolyte upset with low plasma Na+ through the increased urinary elimination and high plasma K+, reduced blood volume, lower blood pressure, marked anaemia, nausea, vomiting, diarrhoea and bronze pigmentation.
- Simnionds Disease
It is caused due to the atrophy or degeneration of anterior lobe of pituitary gland. In this disease, the skin of face becomes dry and wrinkled and shows premature ageing.
- Diabetes Insipidus
It is caused due to the hyposecretion of ADH and characterised by excessive thirst, urination and constipation.,
The retarded mental and physical development is associated with the hyposecretion of thyroid hormones during infancy. The child receives hormones from the mother before birth, so appears normal at first, but within a few weeks or months it becomes evident that physical and mental development is retarded. Symptoms are disproportionately short limbs, a large protruding tongue, coarse dry skin, poor abdominal muscle tone and an umbilical hernia.
- Toxic Nodular Goitre
It is caused due to the excess secretion of T3 and T4 and is characterised by the presence of glandular tissue in the form of limbs.
- Myxoedema (Gull’s Disease)
It is caused due to the deficiency of thyroid hormones after development is complete. Symptoms are abnormally low metabolic rate.
It is caused due to the excessive parathromone secretion usually due to the tumour in parathyroid gland. Its symptoms include kidney stones, indigestion, depression, loss of calcium from bones, muscle weakness.
- Hypoparathyroidism (Tetany)
It is causjed due to the hyposecretion of parathyroid hormones. Its symptoms include muscle spasm, dry skin, numbness in hands and feets.
- Cushing’s Syndrome
It is caused due to the hypersecretion of hormones from adrenal glands (glucocorticoids). Symptoms include adiposity of face and body loss of muscle mass, weakness, fatigue and osteoporosis.
It is a hormonal disorder due to the deficient secretion of testosterone in males. In this case, the .secondary male sex organs, such as prostate gland, seminal vesicle and penis are underdeveloped and non-functional.
The external male sex characters like beard, moustaches and masculine voice fails to develop and sperms are not formed.
It occurs due to the defect in hypothalamus, pituitary, testes or ovaries. In males, less production of testosterone occurs affecting the development of male secondary sexual features.
In females, deficient production of oestrogen occurs resulting in very less development of secondary sex characters.
It is the development of breast tissue in males, that occurs mainly due to the disturbance in oestrogen and testosterone ratio.