(i) Pancreas is an important endocrine gland in human body, which helps in regulating the glucose level in blood by releasing an important hormone called insulin.
(ii) It also secretes digestive enzymes such as amylase.
(iii) It also secretes digestive enzymes such as amylase, lipase etc., which help to breakdown various components of food.
(iv) If pancreas will stop functioning, the person would need to administer insulin injections as well as required to take multiple digestive enzymes pills in order to help the breakdown of food.

Estrogen is produced by the Graafian follicles of the ovary,
Role of Estrogens in the human body:
(i) It brings about the changes that occur during puberty.
(ii) It initiates the process of oogenesis.
(iii) It stimulates the maturation of ovarian follicles in the ovary.
(iv) It promotes the development of secondary sexual characters (breast development, high pitched voice etc).

(i) Application of gibberellins on plants stimulate extraordinary elongation of internode. E.g: Corn and Pea.
(ii) Treatment of rosette plants with gibberellin induces sudden shoot elongation followed by flowering. This is called bolting.
(iii) Gibberellins promote the production of male flowers in monoecious plants (Cucurbits).
(iv) Gibberellins break dormancy of Potato tubers.
(v) Gibberellins are efficient than auxins in inducing the formation of seedless fruit - Parthenocarpic fruits (Development of fruits without fertilization) E.g: Tomato.

(i) Hyperthyroidism is caused due to the excess secretion of the thyroid hormones which leads to Grave's disease.
(ii) This hormone is secreted by the thyroid gland.

Thymus is partly an endocrine gland and partly a lymphoid gland. It is located in the upper part of the chest covering the lower end of trachea.

Functions of Thymosin :
Thymosin is the hormone secreted by thymus.
(i) It has a stimulatory effect on the immune system.
(ii) It stimulates the production and differentiation of lymphocytes.

Adrenal Medulla:
The adrenal medulla is composed of chromaffin cells. They are richly supplied with sympathetic and parasympathetic nerves.
Hormones of adrenal medulla: It secretes two hormones namely
a. Epinephrine (Adrenaline)
b. Norepinephrine (Noradrenaline)
They are together called as "Emergency hormones". It is produced during conditions of stress and emotion. Hence it is also referred as "flight, fright and fight hormone".
Functions of adrenal medullary hormones:
(i) It promotes the conversion of glycogen to glucose in liver and muscles.
(ii) It increases heart beat and blood pressure.
(iii) It increases the rate of respiration by dilation of bronchi and trachea.
(iv) It causes dilation of the pupil in eye.
(v) It decreases blood flow through the skin.

The mineralocorticoids are secreted by zona glomerulosa of cortex of Adrenal gland.
(i) The chief hormone is Aldosterone.
(ii) It helps to reabsorb sodium ions from the renal tubules.
(iii) It causes increased excretion of potassium ions.
(iv) It regulates electrolyte balance, body fluid volume, osmotic pressure and blood pressure.

(i) Growth hormone is produced by anterior to be of pituitary gland.
(ii) GH promotes the development and enlargement of all tissues of the body.
(iii) It stimulates the growth of muscles, cartilage and long bones.
(iv) It controls the cell metabolism The improper secretion of this hormone leads to the following conditions.
Dwarfism:
(i) It is caused by less secretion of growth hormone in children.
(ii) The characteristic features are stunted growth, delayed skeletal formation, retarded sexual development and mental disability.
Gigantism:
(i) Over secretion of growth hormone leads to gigantism in children.
(ii) It is characterised by overgrowth of all body tissues and organs. Individuals attain abnormal increase in height.
Acromegaly: Excess secretion of growth hormone in adults may lead to abnormal enlargement of head, "face,hands and feet.

The endocrine portion of pancreas is made up of Islets of Langerhans.
Structure of Pancreas:
The Islets of Langerhans consists of two types of cells namely alpha cells and beta cells. The alpha cells secrete glucagon and beta cells secrete insulin.
Functions of Pancreatic hormones:
A balance between insulin and glucagon production is necessary to maintain blood glucose concentration.
Insulin :
(i) Insulin helps in the conversion of glucose into glycogen which is stored in liver and skeletal muscles.
(ii) It promotes the transport of glucose into the cells.
(iii) It decreases the concentration of glucose in blood.
Glucagon:
(i) Glucagon helps in the breakdown of glycogen to glucose in the liver.
(ii) It increases blood glucose levels.
Diabetes mellitus :
The deficiency of insulin causes Diabetes mellitus. It is characterised by
(i) Increase in blood sugar level (Hyperglycemia)
(ii) Excretion of excess glucose in the urine (Glycosuria).
(iii) Frequent urination (Polyuria).
(iv) Increased thirst (Polydipsia).
(v) Increase in appetite (Polyphagia).

(i) The thyroid gland is composed of two distinct lobes lying one on either side of the trachea.
(ii) The two lobes are connected by means of a narrow band of tissue known as the isthmus.
(iii) This gland is composed of glandular follicles and lined by cuboidal epithelium.
(iv) The follicles are filled with colloid material called thyroglobulin.
An amino acid tyrosine and iodine are involved in the formation of thyroid hormone. The hormones secreted by the thyroid gland are
(a) Triiodothyronine (T₃)
(b) Tetraiodothyronine or Thyroxine (T₄)
Functions of thyroid hormones:
(i) Production of energy by maintaining the Basal Metabolic Rate (BMR) of the body.
(ii) Helps to maintain normal body temperature.
(iii) Influences the activity of central nervous system.
(iv) Controls growth of the body and bone formation.
(v) Essential for normal physical, mental and personality development. It is also known as personality hormone.
(vi) Regulates cell metabolism.