SKELETAL STRUCTURES
Objectives for Exam #1:
1. Provide information on the various structures and functions of the skeletal system.
2. Describe various skeletal system disorders, including imaging techniques used to
diagnose these disorders.
Part I: Skeletal System Structures, Functions, and Disorders
Your group will have an opportunity to cycle through four different stations. If you complete a
station before other groups, review answers to completed questions, or begin working on the
portfolio assignment.
Station A: Bone Structure
1. Using the model at your table (and p. 72-73 of the Human Body), label all of the following on
the photo below: Include: periosteum, compact bone (where the osteons are), spongy bone
(just a small amount), medullary canal (includes bone marrow).
2. Sketch a single osteon from the model. Label: osteocytes, Haversian (central) canal, blood
vessels (vein, artery), nerve.
3. Fill in the basic functions of the following bone structures (Human Body, p.72).
Structure
Function
Periosteum
Medullary
Canal
21
4. Where is the epiphyseal plate in a long bone, and what occurs in this region of bone until
about the age of 17 (Human Body, p. 74)?
Station B: Skull and Spinal Vertebrae
1. How many bones make up the skull? __________
2. Look at the sutures where bones come together in the skull model and think about the ways
bones come together in other parts of your body (like your knee or hip). How do the suture
joints of the skull differ from most other joints in the human body?
3. From the model at the table (and Human Body, p. 68-69), how many vertebrae (“back
bones”) are in the spine? _____________________
4. There are three main types of vertebrae, in three zones of the spine. ____________
vertebrae support the head, the ______________ vertebrae anchor the ribs, and the
____________ vertebrae provide a strong center of gravity for stable movement. (Human
Body, p. 68-70)
5. There is a model at the table showing the effect of the disease osteoporosis on vertebrae.
Of the three vertebrae, one is normal, one has lost some bone density, the third has a severe
loss of bone density. Which vertebra shows the most bone loss in the model (top, middle,
bottom)? __________________
6. Cartilage discs between the vertebrae absorb forces and give the spine flexibility. The
model of a spinal prolapse (slipped disc) at your table indicates the prolapsed area with a red
color. What is the prolapsed disc touching (causing pain)? __________(also refer to p. 321 of
Human Body)
7. Magnetic resonance imaging (MRI) uses radio waves within a magnetic field. These
images can be used to monitor blood flow through vessels, and subtle changes in tissues.
The lumbar spine MRI can sometimes show whether a disc is herniated (prolapsed, bulging,
ruptured, slipped). It cannot show other conditions like muscle strain. The two lumbar spine
MRIs are taken from two different individuals. Which MRI (A or B) shows a prolapsed disc?
___________
Station C: Arm and Leg Structure
1. Using the model of the full human skeleton and your text, indicate the location of each of
the following bones (arm or leg, upper or lower, such as located in the lower arm).
Bone
Humerus
Femur
Radius
Location
22
Ulna
Tibia
Fibula
2. Referring to the x-rays from two patients, which bone(s) are broken in patient A’s x-ray?
_______________________ In patient B’s x-ray? ________________________
3. Using the model provided of what is commonly called a “hip fracture” in elderly people,
which bone is actually frequently broken? __________________________ The model
indicates different places where the fractures can occur (the red lines). How many
different fractures are shown in the model? ________________________
4. A majority of humans experience disorders associated with the knee joint at some time in
their lives. This is in part due to the degree of impact on the joint through frequent use.
Referring to the model of the knee, which bones come together in the knee joint? (Human
Body, p.76-77)
5. The knee has tendons and ligaments that permit a wide range of movement. Tendons
connect ___________ to ___________, and the ligaments connect ___________ to
____________.
6. Of the various types of joints in the human body you are reading about this week, the knee
joint is classified as a _______________ synovial joint. (Human Body, p.78-79)
7. Find the meniscus in the model. Based on its location, what is the function of the
meniscus? ______________________________________________ If a knee is twisted
quickly, what can happen to the menisci? Considering what the menisci do, why is this
potentially a serious injury?
Station D: Hand and Foot Structure
1. Using the hand model, how many bones are in the hand? _________ (Human Body, p. 64)
2. Loosely sketch and label the locations of the carpals, metacarpals, and phalanges.
3. Try the hand grip “strength test.” How many PSI (pounds per square inch) do you get for
your right hand? _______ Your left hand? _______ Do only a few muscles contract as you
grip, or do many muscles contract together? ___________________
23
4. The hand has similar structure to a foot. The carpals of the hand are equivalent to the
_________________ of the foot. The metacarpals are equivalent to the _________________,
and the phalanges are named the same in hands and feet.
5. X-rays are small amounts of electromagnetic radiation. Soft tissues of the body (skin, fat,
and muscle) allow most of the x-rays to pass through and these tissues appear dark gray on
the x-ray photo. Fewer x-rays pass through denser tissues (bones, tumors, etc.) and these
tissues appear light in the photo. X-rays may show large deviations like a break in a bone,
but do not reveal a lot of detail of internal organs. Looking at the copy of the x-ray provided,
what bone appears to be broken? ________________
24