VII B

 According to the U.S. Centers for Disease Control, heart disease, stroke, cancer, viral and bacterial respiratory diseases, diabetes, and chronic respiratory diseases were among the 10 leading causes of death in the United States in 2021. Which of these listed diseases concerns you most and why? Do you think you’re more likely to develop any one or more of them? If so, why? Have you made lifestyle changes to increase your life expectancy? For example, perhaps you’ve limited your exposure to pathogens or chemicals, or you have changed your diet, increased exercise, etc. If you’ve not made any changes, describe what you might do to avoid some of these listed diseases. Be sure to elaborate in your response. Your journal entry must be at least 200 words in length. 

 Course Textbook(s) Belk, C., & Maier, V. B. (2019). Biology: Science for life with physiology (6th ed.). Pearson. https://online.vitalsource.com/#/books/9780134819082  

BIO 1301, Non-Majors Biology 1

Course Learning Outcomes for Unit VII

Upon completion of this unit, students should be able to:

6. Describe human anatomical systems to include their disease states.
6.1 Describe aspects of the endocrine, skeletal, muscular, and nervous systems.
6.2 Describe various forms of birth control and sexually transmitted diseases (STDs).

Required Unit Resources

Chapter 22: Human Sex Differences

Chapter 23: Zika in Pregnancy

Chapter 24: Study Drugs: Brain Boost or Brain Drain?

Unit Lesson

In this unit, we continue our study of the human body. In Chapter 22, “Human Sex Differences,” we explore
the structures and functions of the skeletal system, muscular system, and endocrine system. In addition, we
learn about basic differences between males and females in these two systems, as well as in other systems.

Thyroid Hormone and Issues

Have you ever wondered how the thyroid hormone was discovered?
You may already know that thyroid hormone requires iodine, and if
the body is deficient in iodine, the thyroid gland swells. This is called
a goiter. More than 3,500 years ago, the Chinese were treating
goiters with seaweed, which contains iodine. This is why iodine is
included in our common table salt (Lynn, n.d.).

British physician Thomas Wharton named the gland thyroid, which
means shield, because its shape resembles that of an ancient Greek
shield. It was not until 1888 that Swiss physician Theodor Kocher
recognized that hypothyroidism could be successfully treated with
desiccated thyroid. In 1909, Kocher won a Nobel Prize for his discovery. In 1914, American chemist Edward
Kendall isolated thyroxine, but a way to manufacture the chemical cheaply was not developed until 1952 by
Rosalind Pitt-Rivers, a British biochemist (Lynn, n.d.).

UNIT VII STUDY GUIDE
Human Physiology

A swollen thyroid gland, known as a goiter
(Bhandari, 2009)

BIO 1301, Non-Majors Biology 2

UNIT x STUDY GUIDE
Title

Andreas Vesalius, 16th Century Medical Titan

Andreas Vesalius was
born in Brussels on the
last day of 1514. At the
age of 19, he began
medical school at the
Paris School of
Medicine (Stewart,
n.d.). At that time, the
study of anatomy had
been dominated for
1,300 years by the
writings of a Roman
physician named Galen,
whose teachings were
considered indisputable
and irrefutable.

Vesalius questioned
Galen’s infallibility,
which resulted in
confrontations with his
teachers. Because of
war between Paris and
the Roman Empire, he

transferred to the Louvain University to complete his medical studies, graduating with a bachelor’s degree in
medicine in 1537 at 22 years of age (Stewart, n.d.).

At 23 years of age, Vesalius was awarded his doctorate by the University of Padua, which then elected him to
be the university’s professor of anatomy and surgery (Stewart, n.d.). In 1540, Vesalius was 25 years old when
he began work on his crowning achievement, a fully illustrated medical textbook entitled De Humani Corporis
Fabrica—The Structure of the Human Body. The work, which consists of around 700 pages bound in seven
volumes, took approximately three years to complete. It was published in 1543 (Stewart, n.d.).

Book printers at the time were just beginning to include illustrations in their books, and Vesalius’ book
contained over 270. Many of these illustrations are acknowledged works of art, still memorable and beautiful
in the field of medicine. In 1564, Vesalius became ill and passed away at the age of 49 (Stewart, n.d.). He
was and remains a Titan in the field of medicine.

Reproduction and Conception

We hear a lot about fertility issues when people are trying to conceive children. Infertility can be caused by
numerous difficulties. The impediment could be structural; after all, the structure of any object determines its
function. It could also be related to chemicals. Wait—we are living beings, what would chemicals have to do
with anything? The answer is that hormones are chemicals that are released by various glands. Have you had
a friend try to conceive a child and was not successful? Remember, in order to form a child, an egg and a
sperm must unite—this is only one of the many steps. The egg and sperm had to first be formed in the
parents and then released. Once they united, forming a zygote, the zygote must implant into the wall of the
uterus. Everything must be precise, and this preciseness is regulated by hormones.

If everything goes well, conception occurs, the embryo develops, the fetus matures, and the baby is born. In
Chapter 23, “Zika in Pregnancy,” we learn about the reproductive structures and functions of the male and
female systems. Why are males physically stronger than females? Is male muscle stronger or better? Do
males have more muscle mass? If you ever found a skeleton in the woods, you could actually identify its
gender strictly from the skeleton, based on several structures. Whose pelvic area would be wider and have a
larger angle? If you think about it, of course, you would realize that it would be the female, since a wider
pelvic area aids in childbirth—it provides a larger passageway for delivery of a baby.

Left: Title page from De humani corporis
fabrica, published in 1543 by Andreas Vesalius
Above: Detail from the title page illustration
showing Vesalius (center left) using a cadaver
for a demonstration for students as well as
members of the Church and the nobility
(University of Glasgow Library, 2002)

(Imperial Magician, 1543)

BIO 1301, Non-Majors Biology 3

UNIT x STUDY GUIDE
Title

We learn the difference between sexual and asexual reproduction. We also learn about human development,
birth-control methods, and sexually transmitted diseases (STDs). Considering the ever-growing population of
the Earth and the personal nature of the subject, this is a very important chapter.

Birth control pills are commonly used to prevent pregnancy, and
other hormonal approaches work pretty much the same way. In
our last unit, we read about negative feedback loops (Belk &
Maier, 2019). One section of the brain is called the
hypothalamus, and it stimulates the pituitary gland by producing
gonadotropin releasing hormone (GnRH). Ovulation occurs
because the pituitary gland releases luteinizing hormone (LH)
and follicle stimulating hormone (FSH). These two hormones
stimulate the ovary to produce estrogen, progesterone, and to
ovulate (Seladi-Schulman, 2018).

If the woman becomes pregnant, the placenta produces steady,
increased amounts of estrogen and progesterone. These
hormones negatively effect the hypothalamus and cause it not to
produce GnRh. Without GnRH, the pituitary does not release LH
or FSH, and the ovaries do not ovulate. Consequently, what
hormonal contraception does is fool the body into “thinking” it is
pregnant (Myers, n.d.). The ovaries do not ovulate during pregnancy. The thyroid system functions in a similar
way, with the hypothalamus secreting thyrotropin-releasing hormone, the pituitary releasing thyroid-
stimulating hormone, and the thyroid releasing thyroid hormone (Sargis, 2018

Sexually Transmitted Diseases (STDs)

You may someday pass on what you learn now about human anatomy and reproduction to someone else.
You may have children already, or you may be planning to have children. One day, you just might have to
have “the talk” about sexual reproduction with one of your children. There are so many misconceptions and
false information, it is important for children to learn the facts. We must help them understand that the choices
they make about sex can have lasting effects on the lives of numerous people.

With sex, pregnancy is not the only concern—another potential issue is sexually transmitted diseases (STDs).
The incidence of STDs is on the rise (Saplakoglu, 2018). What we do today does affect what happens to our
bodies in the future, as some STDs can cause problems later in life, such as cancer, infertility, problems with
pregnancy, or chronic pain (Boskey, 2017). What are the most common STDs? Which ones can be cured?
Which ones cause infertility? How can you tell if someone has an STD? If you cannot answer these
questions, pay special attention to the information about STDs in this chapter; it could save your life.

Nervous System

In the last chapter of these two units, Chapter 24, “Study Drugs: Brain Boost or Brain Drain?” we learn about
the system that controls most bodily functions, the nervous system. We learn about the various structures that
make up the nervous system and what they do. We also learn about a variety of nervous system disorders.

Birth control pills
(ParentingPatch, 2013)

BIO 1301, Non-Majors Biology 4

UNIT x STUDY GUIDE
Title

As you are reading this, there are a multitude of processes going on
in your body. For example, your heart is beating, and your lungs are
moving air into and out of your body. Did you eat recently? If so, you
are digesting food. The list goes on and on. You decided whether
you wanted to read the information on this page. Did you decide that
your heart needed to beat or that digestion needed to occur?
Thankfully, no, those processes are governed by our autonomic
nervous system, and they occur automatically, without conscious
thought or direction. Why do we have to consciously decide to do
some things while others just happen automatically? How do we
consciously decide to raise our arm, move our feet to walk, or use
our eyes to read these words?

Our brain and spinal cord constantly send electrical messages to
control both autonomic and conscious activities. Do we take this for
granted? Probably so. As long as everything works correctly, we
rarely give it another thought; however, as with all organs and
systems, problems can arise. Problems with the nervous system are
not as easily fixed as, say, a broken arm or clogged coronary artery
might be fixed. The brain is very delicate. We cannot explore a
functioning brain or spinal cord because the electrical messages
would be disrupted.

You may remember that Ronald Regan had Alzheimer’s disease.
You have probably seen commercials with Michael J. Fox promoting
research for Parkinson’s disease. What are the differences between
the two diseases? Can we treat them? Can we cure them? What
promise does stem cell research hold for their treatment and cure? You may not have known anyone with
either disease, but it is likely that you will at some point in your life.

Why Learn About Health?

You will be faced with voting for people who take stands on research that could possibly cure one or both
diseases discussed above. For whom did you vote in the last presidential election? What was your
candidate’s stance on this topic? If you do not know, you may have voted for someone who holds different
values concerning various aspects and topics of health care than you do.

Are political reasons the only reason we need to know about our body and health aspects? Of course not; we
each have only one life and one body. This unit and the previous unit provided a foundation to help you
understand how to care for your own body. Hopefully, you know enough now to ask useful questions about
your health. Remember, preventing is generally easier, more effective, and less expensive than curing.

References

Andreas Vesalius. (n.d.). Famous scientists. https://www.famousscientists.org/andreas-vesalius/

Belk, C., & Maier, V. B. (2019). Biology: Science for life with physiology (6th ed.). Pearson.

Bhandari, J. S. (2009). Goiter [Photograph]. Wikimedia https://commons.wikimedia.org/wiki/File:Goiter.JPG

Boskey, E. (2017). What could happen if I don’t get tested for STDs? The downfall of not taking control of

your sexual health. https://www.verywellhealth.com/what-could-happen-if-i-dont-get-tested-for-stds-
3132741

Grm wnr. (2005). Central nervous system [Image]. Wikimedia

https://commons.wikimedia.org/wiki/File:Central_nervous_system.svg

Diagram of a human nervous system;
1—brain, 2—central nervous system,
3—spinal cord
(Grm wnr, 2005)

BIO 1301, Non-Majors Biology 5

UNIT x STUDY GUIDE
Title

Imperial magician [Print on the title page of De humani corporis fabrica by A. Vesalius]. (1543).
https://www.biodiversitylibrary.org/item/191384#page/10/mode/2up

Lynn, J. (n.d.). The history of the thyroid gland. http://endocrinesurgeon.co.uk/index.php/the-history-of-the-

thyroid-gland

Myers, A. (n.d.). What you need to know before taking birth control pills.

https://www.amymyersmd.com/2015/12/birth-control-pills/

ParentingPatch. (2013). Package of Lutera birth control pills [Photograph]. Wikimedia

https://commons.wikimedia.org/wiki/File:Package_of_Lutera_Birth_Control_Pills

Saplakoglu, Y. (2018). STD rates keep rising as US ‘slides backward,’ CDC says.

https://www.livescience.com/63454-std-cases-rising-fourth-year.html

Sargis, R. M. (2018). How your thyroid works. https://www.endocrineweb.com/conditions/thyroid/how-your-

thyroid-works

Seladi-Schulman, J. (2018). Hypothalamus overview. https://www.healthline.com/human-body-

maps/hypothalamus#anatomy-and-function

University of Glasgow Library: Special Collections Department. (2002). De humani corporis fabrica librorum

epitome. http://special.lib.gla.ac.uk/exhibns/month/sep2002.htm

Course Learning Outcomes for Unit VII

Required Unit Resources

Unit Lesson