Endocrine Lab: Chapter 17
Overview:
The endocrine system is a diffuse system, scattered throughout the body. It is composed of
numerous organs that serve strictly an endocrine function (i.e., secretion of hormones) and many
endocrine tissues or cells that are part of larger organs. All endocrine organs and tissues are glands
that are ductless. They secrete these chemical messengers, hormones, into the bloodstream to
travel to distant target tissues where each hormone exerts its actions.
Hormones are chemical signals the body uses to direct biological actions. Each hormone can only
stimulate a response in cells that have receptors for that hormone. The location of the receptor,
membrane bound or intracellular, is dictated by the chemical nature of the hormone. The body
tightly regulates the overall receptor numbers at a target tissue; without receptors hormones have
no ability to cause cells to change their function.
Many homeostatic mechanisms are tightly regulated by hormone actions. Blood glucose levels are
an example of such a mechanism.
This lab has two major components: an anatomical overview and a physiology exercise. Remember
that you will probably need to spend time in open lab to move from familiarity with the information
to understanding the where and how our endocrine system work.
Anatomy Learning Objectives:
1. Students will be able to identify the endocrine glands on the models, figures and cadaver
described in this lab.
2. Students should be able to name the main hormones secreted by each of the endocrine
glands studied.
3. Students should be able to differentiate the various histological structures on the endocrine
slides listed below.
ENDOCRINE GLAND ANATOMY:
Major and minor endocrine glands of the body are part of the way our bodies communicate to
regulate and control growth, metabolism and sexual development and function. (Be sure that your
laboratory period is not spent looking at the book and a torso model, much of this type of review
can be completed in open lab.)
Exercise 1: Organ overview
Part 1: Working in a group of three to four students, gather around a torso model, refer to
figure 17.1, and identify the following major endocrine organs.
1.
2.
3.
4.
5.
6.
7.
8.
Pituitary gland
Pineal gland
Pancreas
Adrenal gland
Thyroid gland
Parathyroid gland
Ovary
Testes
Once organ identification is complete, fill in the function of the hormones secreted by each gland
on the endocrine chart that is part of the laboratory worksheet. In addition to identifying the
function, list any tropic hormones that promote the release of the hormone.
Part 2: As our knowledge of the endocrine system expands, more and more organs appear to have
some endocrine gland function. Some of the glands on the torso model would be considered minor
glands. Identify these minor endocrine glands on the torso model, cadaver and figure 17.1:
1.
Kidney – erythropoietin
2.
Heart -- atrial natriuretic hormone
3.
Liver – angiotensinogen (precursor to Angiotensin II)
4.
Thymus -- thymosins
Again return to the endocrine chart and describe the function of the hormones listed for the minor
endocrine tissues.
Part 3: Finally, a quick nervous system review of the hypothalamus: Open your book to page 515
and use figure 14.2 as a reference. Examine a model of the brain and identify the hypothalamus
on its inferior surface. The hypothalamus is located in the lower central part of the brain. Find the
hypothalamus on the diagram. It is shaped like a funnel that forms the floor and walls of the third
ventricle of the brain (figures 14.2 and 14.12b).
With its intimate tie to the posterior pituitary via the nerve tracts and its connection to the anterior
pituitary via the hypothalamo-hypophyseal portal system (figure 17.4 a and b, page 639), the
hypothalamus is a major control center for many of the hormones in the body. It secretes tropic
hormones that stimulate or suppress the release of hormones from the anterior pituitary, thereby
playing a role in homeostasis. The hypothalamus plays an important role in the regulation of
satiety, metabolism, sex drive and body temperature.
SPECIFIC ENDOCRINE GLANDS: For the remaining anatomical review exercises, you will
need to find the individual structure of the endocrine glands and look at the histology of each.
Exercise 2: Pituitary Gland
Some of the brain models have a pituitary gland depicted, see the very pink bean-sized structure
identified by the blue arrow. The pituitary gland (figure 17.4a and b, p. 639) is suspended from the
floor of the hypothalamus by a stalk (i.e., infundibulum) and is housed in a depression in the
sphenoid bone (i.e., sella turcica of the sphenoid bone). It is physically smaller than a marble, more
like a kidney bean in shape and size. It is composed of two structures: the adenohypophysis (i.e.,
anterior pituitary) and the neurohypophysis (i.e., posterior
pituitary). These two structures have independent origins
developmentally, and have distinct physiological functions.
View figure 17.4a and note that neurons extend from two
brain nuclei (i.e., paraventricular nucleus and supraoptic
nucleus) in the hypothalamus to terminate in the posterior
pituitary. This indicates that the secretions from the posterior
pituitary are neurosecretions and are sometimes called
neurohormones. The paraventricular nucleus is responsible
for the synthesis of oxytocin (which promotes uterine contraction or milk ejection), while the
supraoptic nucleus produces antidiuretic hormone (to counter dehydration and is involved in blood
pressure regulation).
The anterior pituitary is composed of glandular tissue and is involved in the release of 6 different
hormones directly into the bloodstream. Tropic hormones released by the hypothalamus into the
bloodstream control the secretion of anterior pituitary hormones. Look at figure 17.4b and note
the extensive capillary networks associated with the hypothalamus and anterior pituitary. If we
follow the superior hypophyseal artery, it branches into a primary capillary bed right at the base of
the hypothalamus. This capillary bed is drained by portal venules that terminate in a second
capillary bed surrounding the anterior pituitary. This arrangement of vessels connecting two
capillary beds in a series is called a portal system. And this specific one is called the
hypothalamo-hypophyseal portal system.
Part of learning the anatomy of any system is to look at the tissues at a microscopic level. This
examination reveals specific cellular structures and tissue organization you will be required to
know.
Remove slide 34 from the slide box and place on a piece of white paper. Notice with your naked
eye the pituitary gland slide has two distinct parts. The darker stained region is the anterior
pituitary. The lighter stained region is the posterior pituitary. Now, place the slide on the stage of
the microscope and focus on low power. (Remember that you always want to start on low power.)
Scan the slide and find the junction between the anterior pituitary and the posterior pituitary. Now
focus on this junction on high power. Notice that the cells of the anterior pituitary are relatively
cuboidal in shape and have relatively large nuclei. Remember the anterior pituitary is glandular in
nature.
Now focus on the opposite side of the junction. This side has an almost fibrous appearance with
numerous small dark nuclei interspersed. Recall that the posterior pituitary is an extension of the
hypothalamus – brain tissue. It is composed of bundles of axons (the more fibrous appearance -tracts) intermixed with glial cells (the darker, small nuclei) (figure 17.5).
In the space provided on the worksheet, draw what you see in your field of view for the anterior
pituitary and posterior pituitary. Then compare your drawing to that of your peers and also the
website hyperlink for the pituitary. (This is not about how well you draw, rather it is the actual act
of drawing that helps you remember the structures that you are observing at a cellular/tissue
level.)
Go to the endocrine chart on the worksheet and fill in the functions of the hormones of the
anterior (6) and posterior pituitary (2). Most of the hormones of the pituitary are controlled by
negative feedback, with at least one notable exception, oxytocin. Use your text to review these
hormones.
Exercise 3: Thyroid Gland
The thyroid gland is one of the easiest glands to palpate. Run your fingers down your trachea
towards your manubrium (the broad upper part of the sternum). You should feel the cartilaginous
supports of your trachea and you should feel the thyroid gland that spans this structure just caudal
to the thyroid cartilage of the larynx. While our palpation is kind of crude in nature, practiced
physicians learn to detect gland texture as well as size with just their fingers.
The gland itself is butterfly shaped where the two wings create the gland’s bulk as it wraps the
trachea. The two lobes (i.e., the left and right lobes) are attached inferiorly by a bridge-like
structure called the isthmus (figure 17.9a).
Remove slide #4 from the slide box, place the slide on the stage of the microscope and focus on
low power. Advance to high power as you focus at each level. The most notable feature of the slide
is the numerous functional units interspersed throughout the gland called thyroid follicles (figure
17.9b). The walls of the follicle are composed of simple cuboidal epithelial tissue. The lumen of
the follicle is filled with a protein-rich colloid precursor of the thyroid hormones. The follicular
cells encompass the follicle and secrete thyroxine (i.e., T4 or tetraiodothyronine) and
triiodothyronine (i.e., T3). These hormones are collectively called the thyroid hormones.
In the space provided on your worksheet draw what you see in the field of view for the thyroid
gland. Label the thyroid follicle with the colloid inside of it and the follicular cells.
There are also clusters of cells located between the follicles called parafollicular cells. These cells,
also called C cells, are hard to distinguish on a normal slide, but you need to know that these cells
exist and are the source of the hormone calcitonin which helps prevent hypercalcemia. Label the
parafollicular cells in your diagram as well. Once complete, compare your diagram to the website
illustration and to the diagrams of your lab partners.
Exercise 4: Pancreas
The pancreas is an elongated glandular structure (about the texture of cottage cheese). When
looking at the cadaver it is located below and behind the stomach (figure 17.12a). The bulk of the
gland is exocrine tissue involved in the release of digestive enzymes into the small intestine through
the pancreatic duct. Only a small portion of this gland is devoted to endocrine actions.
Remove slide # 20 from the slide box and focus on low power. Quickly step up to high power. The
pancreas contains both exocrine and endocrine cells. Scan the slide and isolate a portion that
shows the darker, exocrine tissue with interspersed with clusters of lighter stained cells of the
endocrine functions derived in the pancreatic islets (figure 17.12b,c).
The exocrine tissue is composed of tightly packed serous acini that appear like rather puffy cell
collections. The histological stain used is specific for the rough endoplasmic reticulum (i.e., RER),
the organelle used to make enzymes and proteins in the cells. Because the serous acini secrete more
digestive enzymes, they have more RER and are therefore stained darker.
The islet cells are less enlarged and are paler in color. A fine capsule that allows it to be
distinguished as a unit surrounds the entire islet, but you will not be able to see this capsule
specifically under the light microscope, instead you will only see that the endocrine cells are packed
together. There are several cell types within each islet including the alpha cells which secrete
glucagon, that increases blood glucose if needed (prevent hypoglycemia), the beta cells which
secrete insulin that decreases blood glucose if needed (prevent hyperglycemia), and the delta cells
that secrete somatostatin which helps regulate digestion as well as secretion of insulin or glucagon.
But to identify these individual cells there would have to be additional staining. Go to the endocrine
chart on the worksheet and fill in the hormones of the pancreatic islets.
Draw the histology of the pancreas as seen in the microscope field of view. Label the serous
acini of the exocrine pancreas and the pancreatic islets. Then compare your diagram to that of the
web picture and that of your classmates.
Exercise 5: Adrenal Gland
The adrenal glands are small, almost triangular shaped glands that are superior to the kidneys
(figure 17.11a). The glands are about the size of a hazel nut. Like the pituitary, the adrenal gland
develops from two distinct glands in the embryo, both with endocrine functions. Identify this
gland on the torso model and from diagrams from your book.
Remove slide # 36 from the slide box and focus on low power. The entire gland is typically
surrounded by a layer of adipose tissue. The capsule surrounds the outside of the gland proper.
Focus on the cortex of the adrenal gland. The outer layer, called the cortex, is the larger of the
layers consisting of about 80-90% of the entire structure, while the inner medulla about 10% of the
entire structure. The cortex surrounds the deep medullary tissue and is a structurally diverse
tissue that can be divided into three layers (from outside toward the medulla): zona glomerulosa,
zona fasciculate and zona reticularis (figure 17.11b). You are not responsible for identifying the
specific cortical layers histologically, but rather should know that the adrenal cortex is involved in
secreting three classes of steroid hormones: androgens, mineralocorticoids and glucocorticoids.
The medulla is both an endocrine organ and a ganglion of the sympathetic nervous system.
Chromaffin cells make up this ganglion and are responsible for secreting the catecholamine
hormones (e.g., epinephrine, norepinephrine and dopamine). Note the highly vascular nature of the
adrenal medulla and ponder how these blood vessels are needed to carry catecholamines to the
body following secretion at these modified sympathetic nerve endings. Fill these hormones in on
the endocrine chart of the worksheet.
Exercise 6: Gonads
The ovary is not only a reproductive organ responsible for oogenesis, but is also an endocrine
organ releasing estrogens and progesterone (figure 28.1). The ovaries are small, almond-shaped
organs. Identify the ovary on the torso model and from the figure in your text. The ovary has a
cortex and medulla, like many of the other organs examined (figure 28.2). The primary hormones
of the ovary are estrogens, progesterone and inhibin. Fill these in on the endocrine chart.
The ovary is surrounded by a fibrous capsule and the cortical stroma is where the ovarian follicles
can be found. The follicles are a collection of epithelial cells and an oocyte surrounded by a capsule
called the theca. The follicles can be at various stages of development, although most are
primordial follicles. (This differs from the diagram in your book that is illustrating the various
stages of development the follicles progress through indicated by the series of black arrows.) Figure
17.13a is a histological view of a mature ovarian follicle. At this stage of development the oocyte
(collectively includes the egg and the egg nucleus) is obvious. Surrounding the oocyte are layers of
granulosa cells that secrete estrogens. Surrounding the granulosa cells are the theca. The
medulla is again the inner region of the organ that is composed of connective tissue and is also
highly vascularized.
Remove slide #40 from the slide box and focus using low power. At this point you should be able
to see the entire ovary section. Notice the cortex and the medulla. Now advance to 100X
magnification. Focus on the cortex and look for a good example of a mature follicle. Isolate that
follicle and examine it under 400x magnification. At this point you should be able to identify the
cortical stroma and the isolated follicle as well as the oocyte, granulosa cells and theca. Draw what
you see in the field of view of the microscope and label these structures.
Return to 100x magnification and find a cluster of darker cells slightly below the follicle layer. This
cell cluster is a corpus luteum and is responsible for progesterone secretion that assists in
maintaining pregnancy. Again draw what you see in the field of view of the microscope and label
this structure. Compare your diagram with that of the study group across the table.
The testes, like the ovary, has two functions: spermatogenesis and sex hormone production.
Testes are paired organs located in the scrotum. They are about the size of walnuts. (figure
27.9a,b,c). In terms of an endocrine organ, the testes must be examined histologically.
Remove slide #12 from the slide box and focus under low power. The most striking feature of
this slide is the numerous seminiferous tubules of the testes (figure 17.13b). The outermost tissue
is the tunica albuginea that surrounds the testicle proper. Advance to high power and focus on a
single seminiferous tubule (figure 17.13b). Sperm cells are produced in these chambers and as
mature spermatids would be found in the luminal area. The outermost layer of the seminiferous
tubule is the germinal epithelium, but it is hard to distinguish from the other cells that are the
sustentacular cells (i.e., Sertoli cells). These sustentacular cells secrete inhibin. In between the
seminiferous tubules are interstitial cells (i.e., Leydig cells) that secrete testosterone. Aside from a
positional arrangement (i.e., between the seminiferous tubules), these interstitial cells are not
distinguishable based on histological staining. Draw what you see in the field of view and label
the seminiferous tubules, germ cells and interstitial cells. Then fill in the hormones of the
testes in the endocrine table.
Exercise 7: Other Endocrine Glands
The pineal gland is a brain endocrine gland located near the posterior end of the corpus callosum.
It is actually attached to the roof of the third ventricle and is considered part of the epithalamus
(figure 14.2). This gland is associated with establishment of the 24-hour circadian rhythms our
bodies experience with the light and dark cycles. Melatonin is a specific hormone of this gland and
may be involved in sleep patterns and in the timing of puberty. Consider the function of this gland
when you wake up at 7am for your 8am class on Saturday morning, or when you experience jet lag
after returning from a vacation in Europe. Locate this gland on a brain model and fill in the
endocrine chart on your worksheet.
The thymus is an immune organ that also has endocrine functions. The organ undergoes
considerable changes with age reaching its peak size at puberty and then undergoes involution. It
lies in the anterior mediastinum and can extend up to the thyroid gland and down towards the 4th
and 5th costal cartilage (figure 17.8a and b). This gland is not obvious on the torso models, so you
only need to know it from the above diagrams.
The thymus is the site for T cell (lymphocytes) development and maturation. Hormones of the
thymus are thymosin, thymopoietin, thymulin and interleukins all involved in the development of a
mature immune system. Fill these in on the endocrine chart on your worksheet.
ENDOCRINE PHYSIOLOGY
Physiology Objectives: (On average, this exercise should take the second half of the class period.)
Upon completion of this exercise students will be able to:
1. Define pre-diabetes and diabetes.
2. Predict pre-prandial and postprandial values for individuals with diabetic, pre-diabetic and
normal blood glucose concentrations.
3. Operate a blood glucose meter, record and interpret results.
4. Display a functional knowledge of diabetes.
Blood Precautions:
It is common practice in the lab to simply assume that every blood, tissue, or fluid sample you deal
with is tainted with something harmful. As a result it is important to remember to wear disposable
gloves whenever you are handling blood or any materials that have come into contact with blood
(even if it is your own). In addition, it is important to wash your hands before leaving the lab after
you have been working with blood. In addition to proper personal protection (i.e., gloves) it is
important to clean any surfaces that may have become contaminated with blood (microscopes,
bench tops, equipment, etc…). Disinfecting solutions will be supplied by the department and will be
in the lab for your use. Anything that comes in contact with blood must be disinfected and materials
that will be disposed of (microscope slides, gloves, lancets) must be placed in designated
“biohazard” receptacles and NOT the regular trash!
Introduction:
Diabetes mellitus is a metabolic disorder that appears to be related to defects in insulin secretion
and/or in defections in target cell responsiveness to insulin. Insulin is the primary hormone in your
body that promotes glucose uptake from the blood into the cells. Insulin is released by the beta
cells in the pancreatic islets. Without insulin, the blood glucose concentration would greatly
increase.
In 2012, 7.3% of Minnesotans had been diagnosed with diabetes (type 1 or 2)1. The problem with
this statistic is that many individuals are unaware that they have diabetes, so the actual number of
residents in the state might be much higher. Most diabetics in the state are 65 years old or older,
but the number of young people being diagnosed is on the rise. This increase among youth appears
to be linked with obesity and inactivity. Overall, diabetes is associated with older adults,
overweight and obese adults, some ethnic groups, people with a family history of type 2 diabetes
and individuals who are sedentary.
It is estimated that over 86 million people in the United States are pre-diabetic, where the
individual’s blood glucose concentration are higher than normal (fasting blood glucose of 70100mg/dL), but not high enough for a diabetic diagnosis2. In Minnesota this value may be as high
as 35% of the adult population. There are three major forms of the disease: Type 1, Type 2 and
gestational diabetes.
The concentration of glucose in the blood is used to give an indication of blood glucose control at
the moment. Although, long-term control of blood glucose is evaluated using glycated hemoglobin
(HbA1c). The assay for glycated hemoglobin reflects blood glucose control over the last three
months because poor glycemic control (periods of hyperglycemia) causing glucose to become
inappropriately attached to hemoglobin molecules.
Blood Glucose Concentrations for Diagnosis of Diabetes
Preprandial Blood
Postprandial Blood
Glucose Concentrations
Glucose Concentrations
Normal Values
< 100 mg/dL
< 140 mg/dL
Pre-diabetes
100 mg/dL – 126 mg/dL 140 mg/dL – 200 mg/dL
Diabetes
> 126 mg/dL
> 200 mg/dL*
Hypoglycemia
< 70 mg/dL
< 70 mg/dL
* random blood glucose measure
“Preprandial” and “postprandial” mean, respectively, before and after eating a meal
In this lab you will be following the case histories for three patients. You will be assessing their
blood sugar levels before and after a meal.
Patient 1 is a 21-year old woman who has experienced weight loss and is generally
concerned about her health. The woman has had no previous health problems, but her
family does have a history of diabetes although she is not sure of the type of the disorder.
She is a typical college senior.
Patient 2 is a 50-year old man complaining of a lack of energy. This patient is overweight
and does not exercise; his diet consists mostly of processes foods. His family has a history of
Type 2 diabetes.
Patient 3 is a 12-year old girl of average size. She complains of frequent urinations and
excessive thirst. She lacks energy and has experienced unexplained weight loss. Her parents
brought her in to the clinic because she is complaining of severe stomach pain.
Exercise 8:
Based on the above descriptions, speculate on the preprandial and postprandial values for each of
the patients. These are your hypotheses. Fill in the appropriate statement areas on your
worksheet.
Students will work in groups of 4. One student will gather all of the necessary materials and
supplies to your table. These include: 2-3 paper towels, gloves for every group member, 6 transfer
pipettes, one glucose meter and 8 glucose meter test strips.
A second group member will collect the designated blood samples from the instructor. Pick up
preprandial and postprandial blood samples for each of the three patients from the front desk. This
means you should have a total of 6 blood samples to analyze.
In the meantime, label the transfer pipettes with a permanent marker so as not to mix up the
samples. Label 2 pipettes for each of the three patients.
Once all of the materials and supplies have been collected at your table, your group is ready
to start:
1. Place a test strip into the glucose meter. Allow the meter to power up and recognize that a
test strip is in place. You should see a blood drop symbol in the meter’s display indicating that the
meter is waiting for a sample. (Make sure everyone in the group knows how to work the meter.
This may mean taking the test strip out and inserting it back into the machine a couple of times.)
2. Once the meter has powered up and is signifying it is ready, place a drop of pre-prandial
blood from patient 1 on the designated test strip (that is in the glucose meter). Immediately
dispose of the transfer pipette into the biohazard bag at your table. Record your results in the
table on the worksheet. Then dispose of the “used” glucose test strip.
3. Repeat this step for all of the other blood samples.
Record your results in the table on your worksheet. Then compare your results to the blood
glucose values in the above reference table and draw conclusions concerning the blood glucose
regulation of the three patients. Finally, address the thought questions on your worksheet as a
lab group.
References:
1.
2.
3.
Hollie E. Ables. 2014. Simulated diabetes testing experiment using artificially manipulated
livestock blood. Thesis for University of Mississippi in partial fulfillment of the requirements
of the Sally McDonnell Barksdale Honors College.
Minnesota Department of Health. 2013.
http://www.health.state.mn.us/diabetes/pdf/DiabetesinMinnesota-2013-final-0317.pdf
http://www.cdc.gov/diabetes/pubs/statsreport14/national-diabetes-report-web.pdf
http://histology.med.umich.edu/node/82 This is the Webscope link
Worksheet for Endocrine Laboratory
This worksheet is designed to help you progress through the lab exercise. Follow the directions and
complete the information.
Exercise 1, Part 1 and 2:
Use a highlighter and identify the pituitary and the hypothalamus.
Fill in the name of the endocrine organs as indicated by the arrows on the torso diagram below:
Some of the organs are deep to the other structures. The ones tinted in blue are deep to the large
and small intestine and liver. Also the male reproductive system is not shown.
Feel free to add any additional organs
that you see fit – this is supposed to be
a work in progress.
Endocrine Hormone Chart: Much of this chart can be completed outside of class but the content
of this table should be understood for the laboratory exam.
Endocrine Organ
Hormone
Pineal Gland
Melatonin
Posterior Pituitary
Oxytocin
Posterior Pituitary
ADH
Anterior Pituitary
Growth
Hormone
Anterior Pituitary
Prolactin
Anterior Pituitary
LH
Anterior Pituitary
FSH
Anterior Pituitary
TSH
Anterior Pituitary
ACTH
Kidney
Erythropoietin
Heart
ANP
Liver
Angiotensin II
Thymus
Thymosins
Thyroid
(follicular cells)
Thyroid
Hormones
Function of Hormone
Tropic Hormone that
causes this hormone to
be released.
Thyroid (C cells)
Calcitonin
Parathyroid Gland
PTH
Pancreas
Insulin
Pancreas
Glucagon
Pancreas
Somatostatin
Adrenal Cortex
Aldosterone
Adrenal Cortex
Cortisol
Adrenal Cortex
Androgens
Adrenal Medulla
epinephrine
Ovary
(granulosa cells)
Estrogen
Ovary
(corpus luteum)
Progesterone
Testes
(sustentacular cells)
Inhibin
Testes
(interstitial cells)
Testosterone
For the following questions, work with your lab partner and adjacent study groups. Follow
along as you work through the laboratory exercises.
Exercise 1, Part 3:
1. What role does the hypothalamus play in controlling the secretions of the pituitary gland?
Exercise 2:
2. Define portal system. Then speculate on the significance of such structures.
Draw your field of view of the pituitary gland as observed under the microscope. Off to one side,
explain in words how you would distinguish the anterior pituitary from the posterior pituitary.
Compare your answer with that of your lab partner.
Exercise 3:
Draw your field of view of the thyroid gland histology. Label the thyroid follicle with the colloid
inside and the follicular cells. Identify where the parafollicular cells (i.e., C cells) should be located.
Exercise 4:
Draw the histology of the pancreas as seen in the microscope field of view. Label the serous acini
and the pancreatic islets. Compare your diagram to that of your lab partner, then write how you
will distinguish the cell types present.
Exercise 5:
In the space below, define cortex and medulla.
Draw the histology of the adrenal gland slide. Label the adrenal cortex and the adrenal medulla.
Then compare your diagram with your study partner and explain to each other the function of the
structures and how you will distinguish these structures on a lab practical.
Exercise 6:
Draw the histology of the ovary slide. Then compare your diagram with your study partner and
explain to each other the function of the structures and how you will distinguish these structures on
a lab practical.
Draw what you see in the field of view for the testes slide. Label the seminiferous tubules, germ
cells and interstitial cells. Compare diagrams and discuss with your study partner how you will
distinguish these structures on a lab practical.
Physiology Section:
State your hypotheses about the three patients and their blood sugar values based on the
clinical information presented in the handout:
Patient 1:
Patient 2:
Patient 3:
Results:
Patient’s Glucose
Concentrations
Patient
Preprandial blood
glucose (mg/dL)
Postprandial
blood glucose
(mg/dL)
Diagnosis/conclusion* (review blood
glucose table above)
Patient 1
Patient 2
Patient 3
*Compare your values to those of the reference table given in the introduction and write your
conclusions in the space provided in the table above.
Address the following thought questions on your worksheet as a group. Then compare your
answers with those of another table.
a.
Are the preprandial and postprandial blood glucose levels different for the three patients?
Why?
b.
Why do doctors recommend exercise for their patients with Type 2 diabetes? Why does
exercise help those with the disease?
c.
A hypothetical patient is a responsible diabetic who exercises regularly, eats healthy, and
takes her medications properly. The patient checks her blood glucose concentration in the
morning after she awakens and it is typically high. Address the following question on your
worksheet: Why is her blood glucose concentration higher in the morning then at other
times of the day?
d.
A patient has been recently diagnosed with diabetes. This patient uses insulin injections in
order to control his diabetes. The patient has experienced a slight weight gain since starting
treatment. Address the following question on your worksheet: What are some possible
reasons for such a weight gain?
e.
A patient with diabetes becomes shaky and light-headed multiple times a week. Address the
following questions on your worksheet: What condition are these symptoms characteristic
of? What are some possible causes of the condition?