Wednesday, March 29, 2006
Answers to 11 endocrine
2–28. ENDOCRINE CONTROL
a. Antidiuretic Hormone. The effect of ADH on the permeability of water through the tubules is very rapid, and changes in the ADH concentration in the blood are only 10 to 15 minutes behind the change in the solute concentration.
b. Renin and Aldosterone. When the sodium concentration in the blood falls to a very low point or when the blood pressure falls (for example, in hemorrhage), special cells in the nephron release a hormone called renin which acts upon a plasma protein (angiotensinogen) to form angiotensin–2. Angiotensin–2, in turn, acts upon the cortex of the adrenal gland to produce aldosterone. Aldosterone increases Na+ reabsorption and thus increases water reabsorption. This increases the plasma volume and the blood pressure.
SOLUTIONS TO EXERCISES, LESSON 11
1. The endocrine glands are organs of internal secretion. Since they lack a duct
system, they are often called ductless glands. They are usually well supplied with blood
vessels to facilitate the release of their secretions into the blood. (para 11-1)
2. A hormone is a chemical required in very small amounts for the proper
development or functioning of the body. Unlike a vitamin, a hormone is produced within
the body.
The blood carries each hormone to its target organ, whose level of activity in turn
affects the endocrine organ. Thus, to ensure the secretion of just the right amount of
hormone, there is a feedback mechanism. (paras 11-2, 11-3)
3. Many of the hormones of the pituitary body are called "tropins" because they
cause development or activity of the tissues. (para 11-4b)
4. Antidiuretic hormone, (ADH) and oxytocin are produced by the hypothalamus
and released from the posterior pituitary gland.
ADH is involved with the resorption or salvaging of water within the kidneys.
ADH is produced under thirst conditions.
Oxytocin is involved with contractions of smooth muscle in the uterus and with
milk secretion. (para 11-5)
5. Somatotropin, thyrotropin, and adrenocorticotropic hormone (ACTH) are
produced by the anterior pituitary gland.
Somatotropin stimulates the growth of the body in general.
Thyrotropin stimulates the thyroid gland to produce its hormones.
ACTH stimulates the adrenal cortex to produce its hormones. (para 11-6)
6. The pineal gland is apparently associated with sexual drive and reproduction.
(para 11-8)
7. Thyroxin and calcitonin are secreted by the thyroid gland.
Thyroxin affects the basal metabolic rate.
Calcitonin is involved with calcium metabolism. (para 11-9)
8. The hormone of the parathyroid gland is parathormone, important in maintaining
the calcium levels of the body. (para 11-10)
MD0007 11-11
9. Two important hormones of the pancreatic islets are insulin and glucagon.
These hormones are concerned with the glucose levels in the body.
(paras 11-11, 11-12)
10. Epinephrine and norepinephrine are produced by the adrenal medulla. These
hormones mobilize the energy-producing organs and immobilize the others. This is
important during the stress reaction, "fight or flight." (para 11-14)
11. Mineralocorticoids, glucocorticoids, and some sex hormones are produced by the
adrenal cortex. Mineralocorticoids are concerned with electrolytes of the body.
Glucocorticoids are known for their anti-inflammatory effects. (para 11-15)
12. The testes produce male sex hormones, known as androgens.
The female sex hormones are the estrogens and progesterone. The tissues
affected by female sex hormones include the endometrium of the uterus and the
milk-producing portions of the mammary glands. During pregnancy, the placenta
continues the production of progesterone. (paras 11-17, 11-18)
End of Lesson 11
a. Antidiuretic Hormone. The effect of ADH on the permeability of water through the tubules is very rapid, and changes in the ADH concentration in the blood are only 10 to 15 minutes behind the change in the solute concentration.
b. Renin and Aldosterone. When the sodium concentration in the blood falls to a very low point or when the blood pressure falls (for example, in hemorrhage), special cells in the nephron release a hormone called renin which acts upon a plasma protein (angiotensinogen) to form angiotensin–2. Angiotensin–2, in turn, acts upon the cortex of the adrenal gland to produce aldosterone. Aldosterone increases Na+ reabsorption and thus increases water reabsorption. This increases the plasma volume and the blood pressure.
SOLUTIONS TO EXERCISES, LESSON 11
1. The endocrine glands are organs of internal secretion. Since they lack a duct
system, they are often called ductless glands. They are usually well supplied with blood
vessels to facilitate the release of their secretions into the blood. (para 11-1)
2. A hormone is a chemical required in very small amounts for the proper
development or functioning of the body. Unlike a vitamin, a hormone is produced within
the body.
The blood carries each hormone to its target organ, whose level of activity in turn
affects the endocrine organ. Thus, to ensure the secretion of just the right amount of
hormone, there is a feedback mechanism. (paras 11-2, 11-3)
3. Many of the hormones of the pituitary body are called "tropins" because they
cause development or activity of the tissues. (para 11-4b)
4. Antidiuretic hormone, (ADH) and oxytocin are produced by the hypothalamus
and released from the posterior pituitary gland.
ADH is involved with the resorption or salvaging of water within the kidneys.
ADH is produced under thirst conditions.
Oxytocin is involved with contractions of smooth muscle in the uterus and with
milk secretion. (para 11-5)
5. Somatotropin, thyrotropin, and adrenocorticotropic hormone (ACTH) are
produced by the anterior pituitary gland.
Somatotropin stimulates the growth of the body in general.
Thyrotropin stimulates the thyroid gland to produce its hormones.
ACTH stimulates the adrenal cortex to produce its hormones. (para 11-6)
6. The pineal gland is apparently associated with sexual drive and reproduction.
(para 11-8)
7. Thyroxin and calcitonin are secreted by the thyroid gland.
Thyroxin affects the basal metabolic rate.
Calcitonin is involved with calcium metabolism. (para 11-9)
8. The hormone of the parathyroid gland is parathormone, important in maintaining
the calcium levels of the body. (para 11-10)
MD0007 11-11
9. Two important hormones of the pancreatic islets are insulin and glucagon.
These hormones are concerned with the glucose levels in the body.
(paras 11-11, 11-12)
10. Epinephrine and norepinephrine are produced by the adrenal medulla. These
hormones mobilize the energy-producing organs and immobilize the others. This is
important during the stress reaction, "fight or flight." (para 11-14)
11. Mineralocorticoids, glucocorticoids, and some sex hormones are produced by the
adrenal cortex. Mineralocorticoids are concerned with electrolytes of the body.
Glucocorticoids are known for their anti-inflammatory effects. (para 11-15)
12. The testes produce male sex hormones, known as androgens.
The female sex hormones are the estrogens and progesterone. The tissues
affected by female sex hormones include the endometrium of the uterus and the
milk-producing portions of the mammary glands. During pregnancy, the placenta
continues the production of progesterone. (paras 11-17, 11-18)
End of Lesson 11
Endocrine worksheet answers
SOLUTIONS TO EXERCISES, LESSON 10
1. Endocrine glands are glands of internal secretion. These glands are also called
ductless glands. Hormones are the secretions produced by endocrine glands.
Target organs are the specific organs or tissues to which hormones are carried by
the bloodstream. This is a feedback mechanism because the activity of the target
organ affects the activity of the endocrine organ. (para 10-1)
2. The fundamental control "system" is the interaction of heredity and environment.
Genes determine the range of potentiality. Environment develops it. Controlling
the tissues and organs in general are the hormones of the endocrine system.
Providing more precise and immediate control of the body structures is the
nervous system. (para 10-2a)
3. Endocrine organs are richly supplied with blood vessels because hormones must
be carried to their target organs by the bloodstream. (para 10-2b)
4. a. Pituitary body.
b. Thyroid gland.
c. Parathyroid glands.
d. Pancreatic islets.
e. Suprarenal (adrenal) glands.
f. Gonads (female--ovaries, male--testes). (para 10-2c)
5. The pituitary body is a small pea-sized and pea-shaped structure. It is attached to
the base of the brain in the region of the hypothalamus. In addition, it is housed
within a hollow of the bony floor of the cranial cavity. The pituitary body is actually
two glands: the posterior pituitary gland and the anterior pituitary gland.
(para 10-3)
6. The posterior pituitary gland is that portion of the pituitary body which comes from
and retains its connection with the base of the brain. The hormones of the
posterior pituitary gland are actually produced in the hypothalamus of the brain.
The two recognized hormones of the posterior pituitary gland are ADH (antidiuretic
hormone) and oxytocin. The first is involved with the resorption or salvaging of
water within the kidneys; it is produced under thirst conditions. The second is
concerned with contraction of smooth muscle in the uterus and with milk
production. (para 10-4)
MD0006 10-12
7. The anterior pituitary gland originates from the roof of the embryo's mouth. It then
attaches itself to the posterior pituitary gland. By means of a venous portal
system, the anterior pituitary gland is connected to the hypothalamus. Here,
certain chemicals known as releasing factors are produced. These are carried to
the anterior pituitary by the venous portal system. They stimulate the anterior
pituitary gland's cells to secrete their specific hormones. In turn, these hormones
stimulate the target organs to produce their own products. This stimulating effect
is referred to as trophic. Two of the hormones produced by the anterior pituitary
gland are somatotrophic hormone and ACTH (adrenocorticotrophic hormone).
The target organs of the first are the growing structures of the body. The second
stimulates the cortex of the suprarenal (adrenal) gland to produce its own
hormones. (para 10-5)
8. The thyroid gland is in the neck region just below the larynx and surrounds the
trachea. The masses on either side of the trachea are the right and left thyroid
lobes. The tissue connecting the two lobes is called the isthmus. It is found
across the front of the trachea. Each lobe of the thyroid gland is supplied by the
superior and inferior thyroid arteries. The primary hormone of the thyroid gland is
thyroxin, which affects the basal metabolic rate (BMR), the level of activity of the
body. (paras 10-6--10-8)
9. The parathyroid glands are located on the posterior aspects of the thyroid lobes.
The hormone produced by these glands is called parathyroid hormone or
parathormone. It is involved with calcium metabolism. (paras 10-9, 10-10)
10. Within the pancreas are distributed small groups of cells known as islets. The two
most commonly recognized hormones of the islets are insulin and glucagon.
Theses hormones are involved with glucose metabolism. (paras 10-11, 10-12)
11. The suprarenal glands are embedded in the fat above the kidney on each side.
Each suprarenal gland has an internal medulla and an external cortex. The inner
portion produces a pair of hormones: epinephrine (adrenalin) and norepinephrine
(noradrenalin). These are involved in the mobilization of energy during the stress
reaction ("fight or flight"). Each suprarenal cortex produces hormones which can
be grouped into three different categories:
a. Mineralocorticoids (for example, aldosterone), which are concerned with the
electrolytes of the body.
b. Glucocorticoids (for example, cortisol), which are concerned with many
metabolic functions and are anti-inflammatory in nature.
c. Sex hormones. (paras 10-13--10-15)
12. In humans, the primary sex organs are known as gonads. These organs produce
sex cells (gametes) and sex hormones. (para 10-16)
MD0006 10-13
13. During the first half of the menstrual cycle, the ovaries produce estrogens. During
the second half, they produce progesterone. These hormones are concerned with
female sexuality and with the preparation of female sex organs for reproduction.
(para 10-17)
14. The testes produce the male sex hormones known as androgens (for example,
testosterone). These hormones are concerned with male sexuality. (para 10-18)
1. Endocrine glands are glands of internal secretion. These glands are also called
ductless glands. Hormones are the secretions produced by endocrine glands.
Target organs are the specific organs or tissues to which hormones are carried by
the bloodstream. This is a feedback mechanism because the activity of the target
organ affects the activity of the endocrine organ. (para 10-1)
2. The fundamental control "system" is the interaction of heredity and environment.
Genes determine the range of potentiality. Environment develops it. Controlling
the tissues and organs in general are the hormones of the endocrine system.
Providing more precise and immediate control of the body structures is the
nervous system. (para 10-2a)
3. Endocrine organs are richly supplied with blood vessels because hormones must
be carried to their target organs by the bloodstream. (para 10-2b)
4. a. Pituitary body.
b. Thyroid gland.
c. Parathyroid glands.
d. Pancreatic islets.
e. Suprarenal (adrenal) glands.
f. Gonads (female--ovaries, male--testes). (para 10-2c)
5. The pituitary body is a small pea-sized and pea-shaped structure. It is attached to
the base of the brain in the region of the hypothalamus. In addition, it is housed
within a hollow of the bony floor of the cranial cavity. The pituitary body is actually
two glands: the posterior pituitary gland and the anterior pituitary gland.
(para 10-3)
6. The posterior pituitary gland is that portion of the pituitary body which comes from
and retains its connection with the base of the brain. The hormones of the
posterior pituitary gland are actually produced in the hypothalamus of the brain.
The two recognized hormones of the posterior pituitary gland are ADH (antidiuretic
hormone) and oxytocin. The first is involved with the resorption or salvaging of
water within the kidneys; it is produced under thirst conditions. The second is
concerned with contraction of smooth muscle in the uterus and with milk
production. (para 10-4)
MD0006 10-12
7. The anterior pituitary gland originates from the roof of the embryo's mouth. It then
attaches itself to the posterior pituitary gland. By means of a venous portal
system, the anterior pituitary gland is connected to the hypothalamus. Here,
certain chemicals known as releasing factors are produced. These are carried to
the anterior pituitary by the venous portal system. They stimulate the anterior
pituitary gland's cells to secrete their specific hormones. In turn, these hormones
stimulate the target organs to produce their own products. This stimulating effect
is referred to as trophic. Two of the hormones produced by the anterior pituitary
gland are somatotrophic hormone and ACTH (adrenocorticotrophic hormone).
The target organs of the first are the growing structures of the body. The second
stimulates the cortex of the suprarenal (adrenal) gland to produce its own
hormones. (para 10-5)
8. The thyroid gland is in the neck region just below the larynx and surrounds the
trachea. The masses on either side of the trachea are the right and left thyroid
lobes. The tissue connecting the two lobes is called the isthmus. It is found
across the front of the trachea. Each lobe of the thyroid gland is supplied by the
superior and inferior thyroid arteries. The primary hormone of the thyroid gland is
thyroxin, which affects the basal metabolic rate (BMR), the level of activity of the
body. (paras 10-6--10-8)
9. The parathyroid glands are located on the posterior aspects of the thyroid lobes.
The hormone produced by these glands is called parathyroid hormone or
parathormone. It is involved with calcium metabolism. (paras 10-9, 10-10)
10. Within the pancreas are distributed small groups of cells known as islets. The two
most commonly recognized hormones of the islets are insulin and glucagon.
Theses hormones are involved with glucose metabolism. (paras 10-11, 10-12)
11. The suprarenal glands are embedded in the fat above the kidney on each side.
Each suprarenal gland has an internal medulla and an external cortex. The inner
portion produces a pair of hormones: epinephrine (adrenalin) and norepinephrine
(noradrenalin). These are involved in the mobilization of energy during the stress
reaction ("fight or flight"). Each suprarenal cortex produces hormones which can
be grouped into three different categories:
a. Mineralocorticoids (for example, aldosterone), which are concerned with the
electrolytes of the body.
b. Glucocorticoids (for example, cortisol), which are concerned with many
metabolic functions and are anti-inflammatory in nature.
c. Sex hormones. (paras 10-13--10-15)
12. In humans, the primary sex organs are known as gonads. These organs produce
sex cells (gametes) and sex hormones. (para 10-16)
MD0006 10-13
13. During the first half of the menstrual cycle, the ovaries produce estrogens. During
the second half, they produce progesterone. These hormones are concerned with
female sexuality and with the preparation of female sex organs for reproduction.
(para 10-17)
14. The testes produce the male sex hormones known as androgens (for example,
testosterone). These hormones are concerned with male sexuality. (para 10-18)
