Download Notes-The Integumentary System (Student Copy)

Functions of skin
The Integumentary System
Human Biology 11
Protect underlying tissues and organs from
________ , ________ , and the harmful
effects of strong ________ .
Control the rate at which water is lost by
________
Excretes small amounts of ________ .
________
Produces oil and ________
The skin has a role in maintaining body
________ . This is an example of
________
Epidermis
Skin is made up of three layers:
________________
2. ________________
3. ________________
1.
The upper layer of our skin. Tough, protective outer
layer. It is about as thick as ________________ over most
parts of the body. The epidermis is constantly
________________ and being ________ . In the epidermis
are three special types of cells:
________________,
________________ &
________________
Types of Cells in Epidermis
____________ produce ________ ,
the pigment that gives skin its color.
All people have roughly the
___________ of melanocytes; those
of dark-skinned people produce
________ melanin.
Exposure to ________ increases the
production of melanin, which is why
people get ________ or ________ .
…Types of Cells in Epidermis
Keratinocytes produce ________ , a type of
protein that is a basic component of hair and
nails. Keratin is also found in skin cells in the skin's
outer layer, where it helps create a protective
barrier.
Langerhans cells help protect the body against
________ .
Because the cells in the epidermis are completely
replaced about every ___________ , cuts and
scrapes heal quickly.
The Dermis
below the epidermis
contains ______________ , ______________ , and
______________ .
Without certain molecules in the dermis, our skin wouldn't
________ when we bend or reposition itself when we straighten
up. These two types of fibers in the dermis, ________ and
________ , help the skin ________ and ________ itself when
In ________ people, some of the elastin-containing
fibers ________ , which is one reason why the skin
looks saggy and wrinkled (most wrinkles are caused by
sun exposure, though!).
we move.
Collagen is strong and hard
to stretch. It is for
________
Elastin, as its name
suggests, is ________ .
Sebaceous Glands
The dermis also contains a person's sebaceous glands.
These glands, which surround and empty into our hair
follicles and pores, produce an oil called ________
(pronounced: see-bum) that lubricates the skin and
hair. Sebaceous glands are found mostly in the skin on
the ________ , _____________ , ________ , and
________ .
…Sebaceous Glands
Most of the time, the sebaceous glands make the right
amount of sebum.
As a person's body begins to mature and develop during
the teenage years, though, ________ stimulate the
sebaceous glands to make more sebum. This can lead
to acne when pores become ________ by too much
sebum and too many dead skin cells. Later in life, these
glands produce less sebum, which contributes to
____________ in older people.
causes of acne
sebaceous cyst
http://www.youtube.com/watch?v=1uCnzTT-15s
Subcutaneous tissue
The bottom layer of our skin
is made up of ____________ ,
____________ , ____________ , and
cells that store ________ .
This layer helps protect the body from
________ and other injuries and helps
it hold in ________ .
Sweat Glands (eccrine glands)
There are two types of sweat-
producing glands.
The eccrine glands are found
everywhere in our bodies,
although they are mostly in
the ________ , ________ ,
and ________________ .
By producing sweat, these
glands help regulate
_____________ , and
________ products are
excreted through them.
…Sweat Glands (apocrine glands)
The other type of sweat-producing
gland, the apocrine glands, develop at
puberty and are concentrated in the
________ and _____________ region.
The sweat from the ________ glands is
thicker than that produced by the
eccrine glands.
This sweat doesn't ________ .
However, bacteria on the skin's surface
break it down and produces
substances that cause body odor.
A normal, healthy adult secretes about
____________ of sweat daily, but this
may be increased by _________,
______ , or a _______ environment.
The Integumentary System
Questions: Answer on a piece of loose-leaf in your binder please.
1. What are the names of the three layers of skin?
2. What types of cells can you find in the top four layers of our skin? What role do these specialized
cells play?
3. How often are epidermal cells replaced?
4. What is the function of the dermis?
5. What two fibers can you find in the middle layer of the skin? What role do these specialized fibers
play?
6. What types of glands surround our hair follicles? What do these glands do?
7. Why do some teens have problems with acne? What types of glands are primarily responsible for
this skin condition?
8. What is the bottom layer of the skin? Which four items make up this bottom layer?
9. What are eccrine glands and what do they do?
10. What are apocrine glands? Where are they located on our body?