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Adrenal Cortex

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Adrenal glands are also called suprarenal glands. There are two adrenal glands one on the top of each kidney. Internally the adrenal gland is divisible into outer cortex and inner medulla. Adrenal cortex Adrenal cortex is divided into three zones : the zona glomerulosa, the zona fasciculata and the zona reticularis. Produces three main types of steroid hormones : mineralcorticoids, glucocorticoids, and androgens. Mineralcorticoids produced in zona glomerulosa help in regulation of blood pressure and electrolite balance. Glucocorticoids affect carbohydrate metabolism. It stimulates the liver to synthesise carbohydrates from non carbohydrates such as amino acids and proteins. It is synthesized by zona fasciculata. Androgens are secreted by zona reticularis which play a role in the growth of axial hair, pubic hair and facial hair during puberty. Adrenal Medulla The medulla secreted two hormones :- 1. Norepinephrine or noradrenaline 2. Epinephrine or adrenaline
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Pancreas

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Pancreas is a heterocrine gland ( mixed gland) found in the folds of the duodenum. A portion of pancreas acts like an exocrine gland and another portion like an endocrine gland. The group of cells of endocrine pancreas is called islets of Langerhans. The cells of islet are of three types, with respect to kind of hormones they secrete. 1. Alpha cells :-     These cells secrete glucagon hormone which causes the breakdown of glycogen to release glucose in the blood. Thereby glucose becomes available to the tissues and organs of the body. 2. Beta cells :-      These cells secrete insulin hormone, which controls the formation of glycogen from glucose in the liver. If insulin is not secreted properly, blood glucose level will keep on rising and after a limit, the kidney will allow the glucose to go out in the urine. This happens in people suffering from diabetes mellitus, who are unable to secrete insufficient amounts of insulin. 3. Delta cells :-     These cells secrete soma
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Parathyroid Gland

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Parathyroid glands  are small   endocrine   glands  in the neck of humans and other  tetrapods . Humans usually have four parathyroid glands, located on the back of the  thyroid gland  in variable locations.   The parathyroid gland produces and secretes  parathyroid hormone  in response to a low blood calcium, which plays a key role in regulating the amount of calcium in the blood and within the bones .  Parathyroid hormone (also known as parathormone) is a small   protein   that takes part in the control of calcium and phosphate   homeostasis , as well as bone physiology. Parathyroid hormone has effects antagonistic to those of   calcitonin . Calcium . PTH increases blood calcium levels by directly stimulating osteoblasts and thereby indirectly stimulating  osteoclasts  (through RANK/RANKL mechanism) to break down bone and release calcium. PTH increases gastrointestinal calcium absorption by activating  vitamin D , and promotes calcium conservation (reabsorption) by the  ki
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Thyroid Gland

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The thyroid gland is a butterfly-shaped organ that is located at the front of the neck. The thyroid gland produces three hormones: Triiodothyronine, also known as T3 Tetraiodothyronine, also called thyroxine or T4 Calcitonin Here, the highlighted portion is the Thyroid Gland. Hormonal output from the thyroid is regulated by Thyroid Stimulating Hormone  (TSH) secreted from the Anterior Pituitary  gland, which itself is regulated by Thyrotrophin - Releasing Hormone  (TRH) produced by the hypothalamus. The thyroid may be affected by several  diseases .   Hyperthyroidism  occurs when the gland produces excessive amounts of thyroid hormones, the most common cause being  Graves' disease , an   autoimmune disorder . In contrast,  hypothyroidism  is a state of insufficient thyroid hormone production. Worldwide, the most common cause is  iodine deficiency .
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Pineal Gland

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The Pineal gland is a small, pea-shaped gland in the brain. It secretes Melatonin hormone ........ Melatonin is a hormone from the pineal gland that helps regulate  biological rhythms  such as sleep and wake cycles. In other words, it's melatonin that directs your internal clock - the one that allows you to wake up about the same time every morning without an alarm clock.                                                                                                                                                                           
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Pituitary Gland

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Pituitary gland is also called as master gland... The pituitary is a pea-sized gland that is housed within a bony structure (sella turcica) at the base of the  brain . The sella turcica protects the pituitary but allows very little room for expansion. It has 3 parts:  1.Anterior lobe (Adenohypophysis)                         2.Intermediate lobe (Pars intermedia)                         3.Posterior lobe ( Neurohypophysis ) It secretes 11 hormones Hormone Target Organ or Tissue Adrenocorticotropic hormone (  ACTH ) Adrenal glands Beta-melanocyte–stimulating hormone Skin Endorphins Brain and immune system Enkephalins Brain Follicle-stimulating hormone Ovaries or testes Growth hormone Muscles and bones Luteinizing hormone Ovaries or testes Oxytocin * Uterus and mammary glands Prolactin Mammary glands Thyroid-stimulating hormone Thyroid
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