Download Integumentary System: Cutting Dead Cells

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Cellular Organization
You have just finished learning about cell. Now it is time to move up in complexity.
There are many different types of cells
(muscle, brain, blood, bone, heart, skin,
etc.). They all look different and carry
out different functions. Their shape
helps them with their job.
Cells don't work along though, they
work together in groups, called tissues.
Tissues work together to perform a specific job. Tissues that
work together are called organs.
Activity #1: Working with a small group (2-3) brainstorm as
many different organs of the human body as
you can (hint: there are as many as 60!)
Groups of organs that work together to carry out specific jobs in the body too.
Groups of organs that work together are called organ systems.
Organ systems work together to form a complete functioning organism
(animal, plant, fungus, etc.)
Activity #2: Working with the same group brainstorm as many different
organ systems of the human body as you can (hint: there are 10 major ones!)
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Activity #3: Match Organ systems to their function
Organ System
organ system #
Description and Function
1. Circulatory
(a) a system made up of the brain, spinal cord, and nerves
that receives and interprets stimuli and transmits impulses to
organs
2. Digestive
(b) a system of blood, blood vessels, lymphatics, and heart
concerned with the circulation of the blood and lymph
3. Endocrine
(c) a system consisting especially of the nose, larynx, trachea,
bronchi, and lungs that controls breathing
4. Integumentary
(d) a system comprising the kidneys, ureters, urinary bladder,
and urethra that regulates urination
5. Muscular
(e) a system that consists of the bones, cartilage, and joints
that supports and protects the body, produces blood cells,
and stores minerals
6. Nervous
(f) a system involving the mouth, stomach, and intestines
that is concerned with the ingestion, digestion, and
absorption of food
7. Reproductive
(g) a system involving especially the pituitary and thyroid
glands, ovaries, and testes that produces secretions and
helps control moods, growth and development, and
metabolism.
8. Respiratory
(h) a system consisting of the skin, hair, nails, and sweat
glands that protects the body and controls body temperature
9. Skeletal
(i) a system involving organs such as the uterus, penis,
ovaries, and testes that deals with making babies
10. Urinary
(j) a system made up of muscle tissue that helps move the
body and move materials through the body
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Skin as an Organ
INTRODUCTION
Did you know that skin is the largest body organ? In this activity, you'll examine the skin and how it functions as an organ
and as part of a larger body system.
EXPLORATION
Go to Organ Systems and read about each of the different organ systems. Remember that the human body is made up of
many organ systems that work together to support body functions.
You will discuss the different organ systems and their parts and functions when you are finished reading. Take notes so
that you can participate in the discussion.
Next, go to and read the Integumentary System site to take a closer look at the skin as an organ and how it interacts with
other systems of the body.
As you’re reading, take notes so that you can answer these questions:
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What structures are associated with the integumentary system?
What are the functions of the integumentary system?
What part does the skin play in your immune system?
How does the integumentary system interact with the digestive system?
Why is it that patches placed on the skin can be used to deliver medications to the bloodstream?
What role does your skin play in the regulation of body temperature?
How important is your skin for the functioning of the nervous system?
As you read the following pages, take notes so that you can answer these questions:
1. What parts of the integumentary system are made up of dead epidermal cells?
2. What is the purpose of the excretory system?
3. What primary organs are involved in the excretion process?
4. What types of waste products are removed through the skin?
5. What organ systems are involved in the creation and excretion of urine?
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Organ Systems
INTRODUCTION
The human body is made up of several organ systems that all work together as a unit to make sure the body keeps functioning. There are ten major organ systems in the
body, each of which plays a different role in helping the body work.
CIRCULATORY SYSTEM
This system is made up of the heart, blood, blood vessels, and lymphatics. It is the body’s delivery system, concerned with circulating blood to deliver oxygen and nutrients to
every part of the body.
DIGESTIVE SYSTEM
The purpose of the digestive system is to turn the food you eat into something useful for the body. When you eat, your body uses this system to digest food so your cells can
use it to make energy. The organs involved in this system include the mouth, stomach, and intestines.
ENDOCRINE SYSTEM
This system is made up of a collection of glands, including the pituitary and thyroid glands, as well as the ovaries and testes. It regulates, coordinates, and controls a number
of body functions by secreting chemicals into the bloodstream. These secretions help control moods, growth and development, and metabolism.
INTEGUMENTARY SYSTEM
This system consists of the skin, hair, nails, and sweat glands. Its main function is to act as a barrier to protect the body from the outside world. It also functions to retain body
fluids, protect against disease, eliminate waste products, and regulate body temperature.
MUSCULAR SYSTEM
This system is made up of muscle tissue that helps move the body and move materials through the body. Quite simply, muscles move you. Muscles are bundles of cells and
fibers that work in a simple way: they tighten up and relax.
NERVOUS SYSTEM
The nervous system is the control center of the human body. It is made up of the brain, spinal cord, and nerves. It receives and interprets stimuli and transmits impulses to
organs. Your brain uses the information it receives to coordinate all of your actions and reactions.
REPRODUCTIVE SYSTEM
The human reproductive system ensures that humans are able to reproduce and survive as a species. It is made up of organs such as the uterus, penis, ovaries, and testes.
RESPIRATORY SYSTEM
The primary function of the respiratory system is to supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body. The respiratory system does
this through breathing. It consists of the nose, larynx, trachea, diaphragm, bronchi, and lungs.
SKELETAL SYSTEM
The skeletal system provides the shape and form for our bodies in addition to supporting and protecting our bodies, allowing bodily movement, producing blood cells, and
storing minerals. This system consists of bones, cartilage, and joints.
URINARY SYSTEM
The purpose of the urinary system is to filter out excess fluid and other substances from your bloodstream. Some fluid gets reabsorbed by your body but most gets expelled
as urine. The organs found in this system are the kidneys, ureters, urinary bladder, and urethra.
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The Anatomy of Skin
The skin is an ever-changing organ that contains many specialized cells and
structures. The skin functions as a protective barrier that faces a sometimeshostile outside environment. It is also very involved in maintaining the proper temperature for the body
to function well. It gathers sensory information from the environment, and plays an active role in the
immune system protecting us from disease. Understanding how the skin can function in these many
ways starts with understanding the structure of the 3 layers of skin - the epidermis, dermis, and
subcutaneous tissue.
Epidermis
The epidermis is the outer
layer of skin. The thickness
of the epidermis varies in
different types of skin. It is
the thinnest on the eyelids at
.05 mm and the thickest on
the palms and soles at 1.5
mm.
The epidermis contains 5
layers of cells.
The bottom layer, the stratum basale, has cells that are shaped like columns. In this layer the cells
divide and push already formed cells into higher layers. As the cells move into the higher layers, they
flatten and eventually die.
The top layer of the epidermis, the stratum corneum, is made of dead, flat skin cells that shed about
every 2 weeks.
Specialized Epidermal Cells
There are three types of specialized cells in the epidermis.
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The melanocyte produces pigment (melanin)
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The Langerhans' cell is the frontline defense of the immune system in the skin
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The Merkel's cell's function is not clearly known
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Dermis
The dermis also varies in thickness depending on
the location of the skin. It is .3 mm on the eyelid
and 3.0 mm on the back. The dermis is composed
of three types of tissue that are present throughout not in layers. The types of tissue are:
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collagen
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elastic tissue
Layers of the Dermis
The two layers of the dermis are the papillary and reticular layers.
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The upper layer contains a thin arrangement of collagen fibers.
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The lower layer is thicker and made of thick collagen fibers that are arranged parallel to the
surface of the skin.
Specialized Dermal Cells
The dermis contains many specialized cells and structures.
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The hair follicles are situated here with the erector pili muscle that attaches to each follicle.
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Sebaceous (oil) glands and apocrine (scent) glands are associated with the follicle.
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This layer also contains eccrine (sweat) glands, but they are not associated with hair follicles.
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Blood vessels and nerves course through this layer. The nerves transmit sensations of pain, itch,
and temperature.
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There are also specialized nerve cells called Meissner's and Vater-Pacini corpuscles that
transmit the sensations of touch and pressure.
Subcutaneous Tissue
The subcutaneous tissue is a layer of fat and connective tissue that houses larger blood vessels and
nerves. This layer is important is the regulation of temperature of the skin itself and the body. The
size of this layer varies throughout the body and from person to person.
The skin is a complicated structure with many functions. If any of the structures in the skin are not
working properly, a rash or abnormal sensation is the result. The whole specialty of dermatology is
devoted to understanding the skin, what can go wrong, and what to do if something does go wrong.
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Integumentary System
Introduction
The integumentary system consists of the skin, hair, nails, glands, and nerves. Its main function is to act as a
barrier to protect the body from the outside world. It also functions to retain body fluids, protect against disease,
eliminate waste products, and regulate body temperature. In order to do these things, the integumentary system
works with all the other systems of your body, each of which has a role to play in maintaining the internal conditions that a human body needs to
function properly.
Functions of the Integumentary System
The integumentary system has many functions, most of which are involved in protecting you and regulating your body’s
internal functions in a variety of ways:
1.
2.
3.
4.
5.
6.
7.
Protects the body's internal living tissues and organs
Protects against invasion by infectious organisms
Protects the body from dehydration
Protects the body against abrupt changes in temperature
Helps get rid of waste materials
Acts as a receptor for touch, pressure, pain, heat, and cold
Stores water and fat
How does the integumentary system work with other systems?
Your body is a complicated system that consists of many subsystems that help to keep it functioning properly.
These subsystems serve a variety of purposes and require needed materials to function properly, as well as means
of communicating information to other parts of the body. Thus, the skin and other parts of the integumentary
system work with other systems in your body to maintain and support the conditions that your cells, tissues, and
organs need to function properly.
The skin is one of the first defense mechanisms in your immune system. Tiny glands in the skin secrete oils that
enhance the barrier function of the skin. Immune cells live in the skin and provide the first line of defense against
infections.
By helping to make and absorb vitamin D, the integumentary system works with the digestive system to encourage the uptake of
calcium from our diet. This substance enters the bloodstream though the capillary networks in the skin. Healthy functioning of your
skin also is related to the digestive system because the digestion and assimilation of dietary fats and oils are essential for the body
to be able to make the protective oils for the skin and hair.
The integumentary system also works closely with the circulatory system and the surface capillaries through your body. Because
certain substances can enter the bloodstream through the capillary networks in the skin, patches can be used to deliver medications
in this manner for conditions ranging from heart problems (nitroglycerin) to smoking cessation (nicotine patches).
The skin also is important in helping to regulate your body temperature. If you are too hot or too cold, your brain sends nerve
impulses to the skin, which has three ways to either increase or decrease heat loss from the body's surface: hairs on the skin trap
more warmth if they are standing up, and less if they are lying flat; glands under the skin secrete sweat onto the surface of the skin
in order to increase heat loss by evaporation if the body is too hot; capillaries near the surface can open when your body needs to
cool off and close when you need to conserve heat.
Your skin plays a vital role in your body as regards the sense of touch. The nervous system depends on neurons embedded in your
skin to sense the outside world. It processes input from your senses, including touch, and initiates actions based on those inputs. For
example, when you stub your toe, nerve cells in the foot send signals up the leg, through the spinal cord, and up into the brain. The
nerve cell connections in the brain sense these signals as pain.
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As well as interacting with the body systems as explained above, the integumentary system also contributes to numerous
physiological processes, especially those involved in the regulation of the body’s internal environment so as to maintain a stable
condition. An example is provided by the way that the skin helps in temperature regulation by changes in the pattern of blood
supply to the skin and by sweating, as mentioned above.
Excretory System: Poison Protection
If you knew there was poison hidden in your house, you would surely do everything possible to find and
remove that poison. If you didn't, you and your family would slowly die. How would you find it? How would
you remove it? You would probably figure out a system of searching and removing. That would be an excretory
system.
Your body does the same thing every day. Hidden throughout your body are dangerous poisons that must be
removed in order for it to survive. The process of excretion involves finding and removing waste materials
produced by the body.
The primary organs of excretion are the lungs, kidneys, and skin. Waste gases are carried by blood traveling
through the veins to the lungs where respiration takes place. Dead cells and sweat are removed from the body
through the skin which is part of the integumentary system.
Integumentary System: Cutting Dead Cells
The body's integumentary system supports the excretory system in the removal of waste. Skin, hair, fingernails
and toenails make up the system by which surface level wastes are removed.
The skin protects the body and also provides for the removal of dead cells and sweat, which contains waste
products. Hair, fingernails and toenails are actually accumulations of dead epidermal cells. As more cells die
and need to be removed, the hair and nails grow.
Activity #4: Now that you have read about the skin, answer the following questions:
1. What parts of the integumentary system are made up of dead epidermal cells?
2. What is the purpose of the excretory system?
3. What primary organs are involved in the excretion process?
4. What types of waste products are removed through the skin?
5. What organ systems are involved in the creation and excretion of urine?
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Skin Connections
REFLECTIONS ON LEARNING
In this lesson, you have been learning about the integumentary and other organ
systems and how these systems work together. Use your notes about what you
have learned to help you complete this student sheet.
Name the organ systems identified in this lesson.
________________________________________________________________________________________________
________________________________________________________________________________________________
________________________________________________________________________________________________
Describe the basic structure and functions of the skin (integumentary) organ system.
Structure
Function
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Give specific examples of organ systems that interact with the integumentary system.
Organ System
Activity #5:
How does it interact with the skin?
Create your own 3D model of skin.
Due: Monday, October 6th, 2014