Download Chapt15 Lecture 13ed Pt 2

Human Biology
Sylvia S. Mader
Michael Windelspecht
Chapter 15
Endocrine
System
Lecture Outline
Part 2
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
1
15.2 Hypothalamus and Pituitary Gland
3. Anterior pituitary gland
• Controlled by hypothalamic-releasing and
hypothalamic-inhibiting hormones
2
15.2 Hypothalamus and Pituitary Gland
3. Anterior pituitary gland
• Hormones _______ by the anterior pituitary
1. Thyroid-stimulating hormone (TSH) stimulates
the thyroid to produce thyroid hormones.
2. Adrenocorticotropic hormone (ACTH)
stimulates the adrenal cortex to produce
cortisol.
3. Gonadotropic hormones stimulate gonads to
produce sex cells and hormones.
3
15.2 Hypothalamus and Pituitary Gland
3. Anterior pituitary gland
4. Prolactin (PRL) stimulates mammary glands
to develop and produce milk only after
childbirth.
5. Melanocyte-stimulating hormone (MSH)
causes skin-color changes in many fishes,
amphibians, and reptiles having
melanophores, special skin cells that produce
color variations.
6. Growth hormone (GH) promotes skeletal and
muscular growth.
4
15.2 Hypothalamus and Pituitary Gland
The hypothalamus and pituitary
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
hypothalamus
1.Neurosecretory cells produce
hypothalamic-releasing and
hypothalamic-inhibiting hormones.
2. These hormones are secreted into
a portal system.
1. Neurosecretory cells produce
ADH and oxytocin.
optic
chiasm
3. Each type of hypothalamic
hormone either stimulates or
inhibits production and secretion
of an anterior pituitary hormone.
2. These hormones move down
axons to axon terminals.
portal system
3. When appropriate, ADH and
oxytocin are secreted from axon
terminals into the bloodstream.
Posterior pituitary
Figure 15.6
Hormones
produced by the
hypothalamus and
pituitary.
Kidney tubules:
antidiuretic
hormone (ADH)
Smooth muscle
in uterus:
oxytocin
Mammary glands:
oxytocin
Anterior pituitary
Mammary glands:
prolactin (PRL)
4. The anterior pituitary secretes
its hormones into the bloodstream,
which delivers them to specific
cells, tissues, and glands.
Thyroid:
thyroid-stimulating
hormone (TSH)
Adrenal cortex:
adrenocorticotropic
hormone (ACTH)
Bones, tissues:
growth hormone
(GH)
Ovaries, testes:
gonadotropic
hormones (FSH, LH)
5
15.2 Hypothalamus and Pituitary Gland
What happens when the body
produces too much or too little GH?
• _______________ – too little GH is produced
during childhood; results in small stature
• __________ – too much GH is produced during
childhood; results in poor health
• __________ – overproduction of GH as an
adult; results in larger than normal feet, hands,
and face
6
15.2 Hypothalamus and Pituitary Gland
What happens when plentiful GH is
produced during childhood?
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Figure 15.8 Growth hormone
influences height.
a.
b.
a: © AP/ Wide World Photos; b: © General Photographic Agency/Getty Images
7
15.2 Hypothalamus and Pituitary Gland
What happens when GH is produced
in high amounts during adulthood?
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Age 9
Age 16
Age 33
Age 52
(all): From Clinical Pathological Conference, “Acromegaly, Diabetes, Hypermetabolism, Proteinura and Heart Failure,” American Journal of Medicine 20 (1956)
133, with permission from Excerpta Medica, Inc.
Figure 15.9 Overproduction of growth hormone in adults leads to acromegaly.
8
15.3 Thyroid and Parathyroid Glands
4. Thyroid gland
• It is a large gland located below the ______.
• _________ is needed in the diet to allow the
thyroid gland to produce its hormones.
9
15.3 Thyroid and Parathyroid Glands
4. Thyroid gland
• It produces
– thyroid hormone (TH) which regulates
metabolism.
– calcitonin which helps lower blood Ca2+ levels
by stimulating the deposition of calcium in the
bones.
10
15.3 Thyroid and Parathyroid Glands
Thyroid abnormalities
• ____________ – thyroid enlarges due to
lack of iodine in the diet
11
15.3 Thyroid and Parathyroid Glands
Thyroid abnormalities
• _____thyroidism – low blood levels of thyroid
hormones
A. Congenital _____thyroidism: thyroid does not
develop properly and is characterized in a
short, stocky person who may have mental
retardation
B. Myxedema: hypothyroidism in adults
characterized by lethargy, weight gain, loss of
hair, cold intolerance, and thick, puffy skin
12
15.3 Thyroid and Parathyroid Glands
Thyroid abnormalities
• _____thyroidism – excess thyroid hormones
in the blood
A. Exophthalimic goiter: characterized by
enlargement of the thyroid gland, protrusion
of the eyes, hyperactivity, and insomnia
B. Thyroid tumor: can also cause
hyperthyroidism
13
15.3 Thyroid and Parathyroid Glands
Thyroid abnormalities
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
affected eye
a. Simple goiter
b. Congenital hypothyroidism
c. Exophthalmic goiter
a: © Bruce Coleman, Inc./Alamy; b: © Medical-on- Line/Alamy; c: © Dr. P. Marazzi/Photo Researchers,Inc.
Figure 15.10 Effects of insufficient dietary iodine, hypothyroidism, and hyperthyroidism.
14
15.3 Thyroid and Parathyroid Glands
5. Parathyroid glands
• Small glands embedded in the surface of the
thyroid gland
• Produces parathyroid hormone (PTH)
– Causes blood Ca2+ level to _________ by
promoting osteoclast activity
– Promotes reabsorption of Ca2+ by the kidneys
15
15.3 Thyroid and Parathyroid Glands
Regulation of blood calcium
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
calcitonin
Thyroid gland
secretes
calcitonin
into blood.
Bones
take up Ca2+
from blood.
Blood Ca2+
lowers.
Homeostasis (normal blood Ca2+)
Blood Ca2+
rises.
Parathyroid
glands
release PTH
into blood.
activated
vitamin D
parathyroid
hormone
(PTH)
Figure 15.11 Blood calcium
homeostasis.
Intestines
Kidneys
absorb Ca2+ reabsorb Ca2+
from digestive from kidney
tract.
tubules.
Bones
release Ca2+
into blood.
16