Find answers, ask questions, and connect with our
community around the world.

Activity Discussion Science & Technology What is endocrine system?

  • Manpreet

    June 11, 2021 at 8:26 pm
    Not Helpful


    A hormone is a chemical substance secreted by the endocrine glands of our body. The endocrine glands are ductless glands, that is, their secretions are directly poured into the blood and get transported to the target organs. These help in the chemical coordination and functioning of the body.

    Hormones are secreted by endocrine glands, for example- pineal gland, pituitary gland, thyroid gland, adrenal gland, pancreas, thymus, parathyroid glands and gonads. Even the heart, liver and kidneys secrete hormones.

    The secretion of hormones is majorly regulated by the Hypothalamus. It controls the hormones of the pituitary.

    The anterior pituitary secretes hormones such as-

    1. Growth hormone (GH) –

    The uncontrolled in its level can cause gigantism and acromegaly whereas its deficiency can lead to dwarfism

    2. Prolactin (PRL) – regulation of growth of mammary glands

    3. Thyroid stimulating hormone – acts on the thyroid gland

    4. Luteinizing hormone – acts on gonads of males

    5. Follicle stimulating hormones – acts on gonads of females

    The posterior pituitary secretes hormones such as-

    1. Oxytocin

    2. Vasopressin

    Thyroid Gland-

    · it secretes T<sub>3</sub> (triiodothyronine) and T<sub>4</sub> (thyroxine)

    · deficiency of thyroid hormones causes hypothyroidism and goitre

    · increase in these hormones causes hyperthyroidism and

    Parathyroid Gland-

    · it regulates the calcium levels of bones and blood

    · takes up extra Ca<sup>2+</sup> ions from the bones and releases it in blood

    Adrenal Gland-

    · adrenal cortex- hormones secreted through these regulate carbohydrate metabolism

    · its deficiency leads to Adison’s Disease

    · adrenal medulla – secretes hormones such as epinephrine and norepinephrine

    · these help in flight or fight, that is, running away in times of danger or facing them


    · these secrete hormones through 3 types of cells

    · alpha cells- secrete glucagon

    – regulates blood glucose levels:

    – increase of blood sugar causes hyperglycemia

    – deficiency causes- hypoglycemia

    · beta cells- secrete insulin

    – these also regulate blood glucose levels

    – their deficiency causes diabetes mellitus

    · delta cells- secrete somatostatin


    · testis are situated in the scrotal sac of man

    · these secrete androgens – testosterone

    · testosterone acts for the development of male accessory organs, secondary sexual characters

    · it regulates the formation of sperms


    · the primary sex organ of female

    · it secretes estrogen and progesterone

    · estrogen helps in the development of mammary glands., female secondary sexual characters and regulates the formation of follicles

    · progesterone acts during pregnancy

    These were the hormones secreted by the endocrine glands. The list extends to numerous hormones. To sum up, hormones play major roles in our body and life. Without these messengers our body would not work efficiently. A healthy diet plays an important role in their regulation. Their deficiencies, if detected early, can treated by using supplements prescribed by the doctor.

For Worksheets & PrintablesJoin Now