Human A&P Warm Up
When the carnival came to town, the local health professionals and consumer groups joined forces to enforce truth-in-advertising laws to protect selected employees of the carnival. They demanded that the fat man, the dwarf, the giant, and the bearded lady be billed as “people with endocrine system problems”. Identify the endocrine disorder in each case and explain how the disorder produced the characteristic features of these four show people.
Warm Up continued
• Fat man
• Dwarf
• Giant
• Bearded lady
• T3 & T4 not being produced efficiently
• GH deficiency
• Hypersecretion of GH
• Tumor on the adrenal cortex
Thyroid GlandThyroid Gland
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Found at the base of the throat
Consists of two lobes and a connecting isthmus
Produces two hormones Thyroid hormone
Calcitonin
Thyroid GlandThyroid Gland
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Figure 9.6
Thyroid HormoneThyroid Hormone
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Major metabolic hormone
Composed of two active iodine-containing hormones
Thyroxine (T4) – secreted by thyroid follicles
Triiodothyronine (T3) – conversion of T4 at target tissues
CalcitoninCalcitonin
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Decreases blood calcium levels by causing its deposition on bone
Antagonistic to parathyroid hormone
Produced by C (parafollicular) cells
Figure 9.9
Conditions of Thyroid Gland
Goiter: enlargement of thyroid due to iodine deficiency.
Cretinism: Dwarfism coupled with mental retardation; caused by a hyposecretion of T4
Myxedema (hyposecretion in adults): mental and physical sluggishness
Graves disease (hypersecretion in adults): high metabolism, intolerance to heat, rapid heartbeat, weight loss, nervous, & agitated
Parathyroid GlandsParathyroid Glands
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Tiny masses on the posterior of the thyroid
Secrete parathyroid hormone
Stimulate osterclasts to remove calcium from bone
Stimulate the kidneys and intestine to absorb more calcium
Raise calcium levels in the blood
Hormones of the OvariesHormones of the Ovaries
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Estrogens Stimulates the development of secondary
female characteristics
Matures female reproductive organs
Helps prepare the uterus to receive a fertilized egg
Helps maintain pregnancy
Prepares the breasts to produce milk
Hormones of the OvariesHormones of the Ovaries
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Progesterone
Acts with estrogen to bring about the menstrual cycle
Helps in the implantation of an embryo in the uterus
Hormones of the TestesHormones of the Testes
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Produce several androgens
Testosterone is the most important androgen Responsible for adult male secondary sex
characteristics
Promotes growth and maturation of male reproductive system
Required for sperm cell production
Conditions of the Reproductive/Endocrine Organs
• Hyposecretion of testosterone can cause a male to be sterile.
• Hyposecretion of ovarian hormones will reduce a females chances to conceive and bear children.
Other Hormone-Producing Tissues Other Hormone-Producing Tissues and Organsand Organs
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Parts of the small intestine
Parts of the stomach
Kidneys
Heart
Many other areas have scattered endocrine cells
Endocrine Function of the PlacentaEndocrine Function of the Placenta
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Produces hormones that maintain the pregnancy
Some hormones play a part in the delivery of the baby
Produces HCG in addition to estrogen, progesterone, and other hormones
hCG
• hCG is the hormone that is detected in pregnancy test sold over the counter.
• hCG stimulates the continued production of estrogen and progesterone so that the lining of the uterus does not slough off
Developmental Aspects of the Developmental Aspects of the Endocrine SystemEndocrine System
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Most endocrine organs operate smoothly until old age Menopause is brought about by lack of
efficiency of the ovaries
Problems associated with reduced estrogen are common
Growth hormone production declines with age
Many endocrine glands decrease output with age
Closure
• A young girl is brought to the clinic by her father. The girl fatigues easily and seems mentally sluggish. You notice a slight swelling in the anterior neck. What condition do you suspect? What are some possible causes and their treatments?
• Hypothyroidism; iodine deficiency----treat with iodine