HORMNOES AS MEDIATOR DEVELOPMENT

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HORMNOES AS MEDIATOR DEVELOPMENT

• By
• M.THILAKAR
• LS1154
• M.SC IN LIFE SCIENCES
• SECOND YEAR
• BHARATHIDASAN UNIVERSITY,
• TIRUCHIRAPALLI

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What is the Hormone???

• A hormone is a chemical released by a cell or a
  gland in one part of the body that sends out
  messages that affect cells in other parts of the
  organism.
• Like messenger molecules in the body.
• Hormones secreted by Glands.
• They play Important role in Growth and other
  functions.

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What are the Hormones play in Growth..???

• Pituitary gland Hormones
• Growth hormones
• Thyroid hormones
• Sex hormones
• Estrogens and
• Progesterones

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Pituitary gland Hormones

• The pituitary gland is a controlling gland, and
  the hormones that it secretes into the blood
  stream will control the actions of many other
  glands within the body. For this reason the
  pituitary is also known as the master gland
• Adult function is not clear.
• But in the child it is necessary for growth
  without it dwarfism results.
• Secretion by the Pituitary is controlled by a
  substance sent to it from an adjacent part of the
  brain.
• Children who lack it are fat as well as small
• When given it by Injection, they lose fat and
  grow rapidly.

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Growth Hormone

• Human growth hormone (somatotropin) is the
  pituitary released hormone that is essential for
  the normal growth and development of a child to
  an adult.
• Without sufficient levels of the hormone, a child
  will never reach their full growth potential.
• Adults also produce GH, and the hormone continues
  to play an important regulatory role throughout
  our lives.
• GH is produced from the pituitary, which is found
  within the hypothalamus in the brain.
• With insufficient levels of GH, the crucial
  metabolic processes within the body will not work
  well.

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Thyroid hormones

• Thyroid hormone from the thyroid gland in the
  neck is necessary for normal growth.
• Without thyroid hormone, however, cells do not
  develop and function properly, especially in
  the brain.
• Babies who lack thyroid hormone at birth are
  small and have insufficiently developed brains.
  they are known as cretins.
• if the condition is diagnosed and they are
  treated with thyroid hormone at once, they
  recover completely.

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Thyroid hormones cntd.

• Thyroid lack may also develop later in childhood,
  when it causes a slowing of growth rate.
• If longer they go without treatment, the more
  likely it is that the brain damage will be
  permanent.

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Testosterone

• Testosterone, secreted by the interstitial cells
  of the testis, is important not only at puberty
  but before.
• Its secretion by the fetal testis cells is
  responsible for the development of certain parts
  of the male genital apparatus.
• If testosterone is not secreted at a particular
  and circumscribed time, the genitalia develop
  into the female form.

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Estrogens

• The female sex hormones, collectively
  called estrogens are first secreted in quantity
  at puberty by cells in the ovary.
• They cause growth of the uterus, vagina,
  and breast.
• They act also on the bones of the hip, causing
  the specifically female widening.

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Sex Hormones

• The pituitary secretes two other hormones
  concerned in development of Sex Hormones.
• Follicle-stimulating hormone (FSH), causes growth
  of the main portions of the ovary in the female
  and the sperm-producing cells in the testis of
  the male.
• Luteinizing hormone (LH), causes growth and
  secretion of the testosterone-secreting cells of
  the male and has an action in controlling the
  menstrual cycle in the female.

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Brain in Sex Hormone

• The signal to start the sequence of events is
  given by the brain, not the pituitary.
• Just as the brain holds the information on sex,
  so it holds information on maturity.

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• Thank you..