Overview ......................................................................................... 1
What is the Lab? ............................................................................. 2
Concepts ......................................................................................... 2
Objectives........................................................................................ 3
Arizona Science Standards .............................................................. 3
College and Career Ready ELA Standards ....................................... 4
Next Generation Science Standards ............................................... 4
Learning Progressions ..................................................................... 5
Brief Background Information ........................................................ 6
Extended Background Information for Teachers............................ 6
Vocabulary .................................................................................... 13
Links and References .................................................................... 14
2nd – 6th grade
At the beginning of the bone lab, participants are prompted with
questions regarding what they know about bones and their
personal experiences with bones.
Participants then spend approximately 15 – 20 minutes working in
groups at tables using a variety of instruments, ranging from
tweezers to microscopes, to explore sterilized cow bones. Safety
procedures are discussed and all participants wear goggles and
gloves. One or more facilitators float from table to table to assist
students and encourage in-depth open exploration of the bones.
After this period of open exploration, the groups sit together to
discuss their discoveries about bones. Family groups may
converse among themselves. Based on what participants have
observed, the facilitator will discuss and break down the meaning
of the new information. The facilitator is encouraged to prompt
the participants to come up with ideas as to why they think a
bone has hard and soft parts.
The facilitator then leads the participants in a discussion about
how bones heal including any personal experiences they wish to
share. Participants learn about bone remodeling and are shown
an animation or illustration about how bones heal. For student
groups, the Busy Bones lab concludes with participants having an
opportunity to share with their group what they learned about
bones. Through dialogue with the facilitator, they will realize that
bones are active and dynamic and are just one component of the
complex nature of the human body.
With family groups, the Busy Bones lab may conclude with
families sharing amongst themselves.
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Arizona Science Center, azscience.org
1
Busy Bones is a 45-minute, facilitator-led lab activity for students
in grades 2-6.
At the beginning of the bone lab, participants are prompted with
questions regarding what they know about bones and their
personal experiences with bones.
Students then spend approximately 15 – 20 minutes working in
groups at tables using a variety of instruments, ranging from
tweezers to microscopes, to explore sterilized cow bones. Safety
procedures are discussed and all participants wear goggles and
gloves. One or more facilitators float from table to table to assist
students and encourage in-depth open exploration of the bones.
After this period of open exploration, groups sit together to
discuss their discoveries about bones. Based on what students
observed, the facilitator will discuss and break down the meaning
of the new information. The facilitator is encouraged to prompt
the students to come up with ideas as to why they think a bone
has hard and soft parts.
The facilitator then leads the participants in a discussion about
how bones heal including any personal experiences they wish to
share. Participants learn about bone remodeling and are shown
an animation or illustration about how bones heal.
The Busy Bones lab concludes with students having an
opportunity to share with their group what they learned about
bones. Through dialogue with the facilitator, they will realize that
bones are active and dynamic and are just one component of the
complex nature of the human body.
Return to Table of Contents
Bones are much more complex than you might imagine.
Bones are made up of active, living tissue that has amazing
abilities to heal itself when injured.
Bones are one example of the body’s complex and dynamic
nature.
Different bones are made up of different types of cells and
materials that have different properties.
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Broken bones can heal themselves through a 4-stage healing
process.
Children may think bones are inert white sticks that hold you up.
They don’t always know that bones are connected to each other
and how they are connected.
They may think the heart stores, cleans, filters, and manufactures
blood.
Blood cells are suspended in a red liquid, or blood is red cells
without intercellular liquid; blood is cells without plasma.
.
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Students handle dissection equipment and conduct observations
of bone tissue samples.
Through dialogue with the facilitator, students will realize that
bones are active and dynamic and are just one component of the
complex nature of the human body.
Students will learn the different components of the healing
processes of broken bones.
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S1C4PO3
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SL.2.1.
SL.2.2.
SL.2.3.
L.2.4.
SL.3.1.
SL.3.2.
SL.3.3.
SL.3.6.
RI.3.4.
L.3.4
SL.4.1.
SL.4.2.
SL.4.3.
L.4.4
RI. 4.4
W.4.9
RF.5.3
SL.5.1.
SL.5.2.
SL.5.3.
L.5.4
SL.6.C.1
SL.6.C.2
SL 6.4
L. 6.4
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2-PS1-1.
2-PS1-2.
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4-LS1-1.
MS-LS1-1.
MS-LS1-3.
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Basic Functions (3-5)
Defense
 Some germs may keep the body from working properly. For
defense against germs, the human body has tears, saliva, and
skin to prevent many germs from getting into the body and
special cells to fight germs that do get into the body.
Basic Functions (6-8)
Defense
 Specialized cells and the molecules they produce identify and
destroy microbes that get inside the body.
 Specialized cells and the molecules they produce identify and
destroy microbes that get inside the body.
Basic Functions (9-12)
Defense
 The human body is a complex system of cells, most of which
are grouped into organ systems that have specialized
functions. These systems can best be understood in terms of
the essential functions they serve for the organism: deriving
energy from food, protection against injury, internal
coordination, and reproduction.
Laboratory experiences in life sciences
Grades 1 – 13
Objects have properties that can be measured and explained.
Three important properties are mass, weight, and volume
Grades K – 8
 Objects have properties that can be measured and explained.
Three important properties are mass, weight and volume.
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Good measurements provide more reliable and useful
information about object properties than common sense
impressions
Grades K – 8
 We can learn about the world through measurement
Arguments use reasoning to connect ideas and data
Grades K – 8
 We can learn about the world through argument
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Bones are much more complex than you might imagine. They
have:
 Different colors
 Hard and soft areas
 Texture (Rough areas vs. smooth areas)
 Layers
 Remnants of blood vessels and connective tissue
Bones are very busy all the time. They are made up of active,
living tissue that has amazing abilities to heal itself when injured.
Our old bone is replaced with new bone every day
Bones are one example of the body’s complex and dynamic
nature.
Different bones are made up of different types of cells and
materials that have different properties.
Broken bones can heal themselves through a 4-stage healing
process.
Return to Table of Contents
Children often have many misconceptions about bones. For
example, it is not uncommon for kids to perceive bones as hard
sticks that have no relation to the rest of the body or any
connection to each other. They may also think of bones as nonliving material, or, if they do think bones are living, that they are
made of only one type of cell.
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The human body is made up of an endoskeleton (internal
skeleton) made up of cartilage and bone. The adult human body
has about 206 bones.
The bones of the human skeleton perform several functions:
 Support (tendons attach bones to muscles and ligaments
attach bones to each other)
 Protection of internal organs from mechanical damage (i.e.
skull and ribs)
 Serve as a reservoir for both calcium and phosphate, which
can be released into the blood stream and utilized by the body
as needed
 Are the source of all blood cells
 Store fat in yellow bone marrow, which the body uses as a last
resort in cases of extreme starvation.
Bones are definitely not simple white sticks that hold us up. They
are much more complex than that! Bones are an active and
dynamic combination of living cells and nonliving minerals. We
call this a matrix (network) of organic (living) and inorganic
(nonliving) materials. Aside from this bone matrix, bones also
have blood vessels, nerves, and connective tissue that are vital to
its growth and repair.
Cross Section of a Long Bone
Source:
http://en.wikipedia.org/wiki
/Bone
Bones are a matrix of organic and inorganic materials. One
component of a bone matrix is collagen. Collagen is a very
important organic protein in bone because it provides the bone
with both strength and flexibility. It helps the bone resist snapping
and breaking (kind of like how cords in a tire sidewall work).
Because of collagen, bones are not brittle white sticks. Collagen is
found in layers in between the inorganic minerals (calcium and
phosphate) of the bone and is perhaps as much as 25-30% of the
organic material in bone.
Another component of a bone matrix are the inorganic minerals –
mostly calcium and phosphorous. They are stored in between the
layers of collagen. Calcium and phosphorous are important
because, among many other things, they help give the bone its
hard outer texture, tensile strength, and rigidity. When there is
not enough calcium in our body, our bones get weaker. Matured
bone contains approximately 65% mineralized matter, the rest
being collagen and matrix (i.e. bone marrow).
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Calcium and phosphorous help make what is called compact
bone. Compact bone is the hard outer layer of bones (like a shell).
It is called compact bone because there are no gaps or spaces in
the bone. The absence of gaps or spaces gives the compact bone a
smooth, white, and solid appearance. Compact bone comprises in
80% of the bone mass in an adult skeleton.
The inner layer of bone is called the spongy bone. This part of the
bone is more porous (has holes) which allow for the presence of
blood vessels and bone marrow. Spongy bone comprises 20% of
bone mass.
Bone marrow is another important component of the bone
matrix. Bone marrow is a gelatinous organic tissue (tissues are a
group of identical cells) found within the cavities of spongy bone
in some of our bones, such as the hip and thigh. Bone marrow
contains stem cells which give rise to the different blood cells.
There are two kinds of bone marrow: red marrow and yellow
marrow. Red marrow produces red blood cells, platelets, and
white blood cells and is found in the ends of long and flat bones
(i.e. femur, ribs, vertebrae, and pelvic bones). Yellow marrow
stores fat and is found in the middle of long bones (i.e. most of
the bones of our limbs).
Thus, bones are very important on a macro level for support and
protection, and at the micro level for storing and releasing vital
minerals and fat.
In general, healing is a complex process of repairing cells as well
as replacing dead cells. This allows for the healing of tissues. Most
parts of our body can heal itself removing old dead cells and
replacing them with new ones (i.e. skin, intestines, mouth, blood).
This is true for both the healing of injuries as well as healing the
daily wear and tear of our bodies.
As stated earlier, bones is made of tissue that themselves are
made up of cells that are dynamic and active at a molecular level.
Bones are constantly changing in a process called bone
remodeling. Bone remodeling is a process of resorption (the
process of losing substance so it can be reabsorbed for another
use in the body) and replacement of bone, with little change to
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the bone’s shape. Approximately 10% of our bone mass is
removed and replaced each year.
There are three types of primary cells that are responsible for
bone remodeling and growth. They are: Osteoclasts, Osteoblasts,
and Chondroblasts. All three cells originate in bone marrow. The
prefixes and suffixes below will help you remember what they do:
Osteo-___
=
___-clast
=
___-blast
=
Chondro-__ =
bone
broken
build or embryonic
cartilage
Osteoclasts (see left – picture of osteoclasts breaking down
bone) are cells responsible for breaking down old and damaged
bone. Osteoclasts break down the calcium and phosphorous in
the bone (by secreting hydrogen ions which dissolves the mineral
matrix) so the minerals can be re-used for other bodily functions.
Osteoblasts (see left – picture of osteoblasts) are cells
responsible for creating new bone tissue. A “blast” is a type of cell
capable of building tissue.
Chondroblasts are cells that build cartilage.
When a bone is broken, the body triggers a repair sequence
deploying osteoclast, osteoblast, and chondroblast cells. These
three cells are vitally important in the “remodeling” process of the
bone and work in conjunction with yet other cells to heal the
bone.
When a bone breaks, the first thing that happens is that a blood
clot forms at the injured area. The blood clot, called a fracture
hematoma, forms because blood vessels have been broken
around the injury (blood vessels run down the length of the
bone). This blood clot helps stabilize the bone and initiates the
healing process by forming a tough tissue at the injured site. This
tough tissue is called a soft callus. It is like chicken wire and
plaster.
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Once a soft callus is formed, special cells called fibroblasts (fibro =
fiber; blast = build) begin producing fibers of collagen. Remember
that collagen is important in giving bone flexibility. It is like
caulking.
Chondroblasts (chondro = cartilage; blast = build) produce a type
of cartilage called fibrocartilage. This fibrocartilage transforms the
soft callus into a tougher fibrocartilaginous callus. This
fibrocartilaginous callus forms a bridge between the two pieces of
broken bone. This process takes about three weeks. It is like a
scaffold or brace.
Osteoblasts then make their grand entrance. They begin
producing bone cells to reinforce the bridge created by the
chondroblasts. Thus the fibrocartilaginous callus now becomes a
bone callus which is needed to protect and stabilize the bone for
final stages of healing. This process takes three to four months.
This is like pouring concrete.
Once this is done, osteoclasts and osteoblasts work together to
replace the bone callus with harder compact bone and return the
bone to the shape it was before it was broken. At first, healed
bones are often not smooth or even since it takes some time for
the bone to be smoothed out to its original shape. This is like
cement workers polishing and sanding (with sandpaper and
chisels).
The final step in healing is that calcium and phosphorous are
added to strengthen the bone. These minerals are stored in the
bone marrow and are released into the blood system to be used
in the healing process.
Osteoporosis, which means "porous bones," is a disease in which
the density and quality of bone are reduced, causing the bones to
become weak and brittle. Bones may become so brittle that a fall
or even mild stresses like bending over or coughing can cause a
fracture. In many cases, bones weaken when there is a low level
of calcium and other minerals in the bones. The loss of bone
occurs silently and progressively. Although it's often thought of as
a women's disease, osteoporosis affects men too. Often there are
no symptoms until the first fracture occurs.
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Figure. Left: normal bone,
right: osteoporotic bone
Scientists don't yet know exactly why osteoporosis occurs, but
they do know that the normal bone remodeling process is
disrupted. As discussed earlier, bone is continuously changing.
New bone is made and old bone is broken down.
During youth, our bodies’ makes new bone faster than it breaks
down old bone and our bone mass increases. Peak bone mass is
reached around age 30. After that, bone remodeling continues,
but we lose slightly more bone than we gain.
Source:
http://www.iofbonehealth.o
rg/patients-public/aboutosteoporosis/what-isosteoporosis.html
How likely a person is to develop osteoporosis depends on how
much bone mass they attained in their 20s and early 30s (peak
bone mass) and how rapidly it is lost later in life. The higher the
peak bone mass, the more bone a person has "in the bank" and
the less likely they are to develop osteoporosis as they age.
The strength of bones depends on their size and density; bone
density depends in part on the amount of calcium, phosphorus
and other minerals bones contain. When bones contain fewer
minerals than normal, they're less strong and eventually lose their
internal supporting structure.
Risk factors for osteoporosis fall into two main categories, fixed
and modifiable.
Although fixed factors (which include age, gender, and family
history) largely determine whether a person is at heightened risk
of osteoporosis, modifiable factors (lifestyle) play a key role as
well. Modifiable factors, like good nutrition and exercise, help
build bone during youth, and help to slow down bone loss in
adults and the elderly.
A number of factors can increase the likelihood that a person will
develop osteoporosis — some can be changed, others cannot.



Being a woman. Fractures from osteoporosis are almost twice
as common in women as they are in men.
Getting older. The older you get, the greater your risk of
osteoporosis.
Race. You're at greatest risk of osteoporosis if you're white or
of Asian descent.
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









Family history. Having a parent or sibling with osteoporosis
puts you at greater risk, especially if you also have a family
history of fractures.
Frame size. Men and women who are exceptionally thin (with
a body mass index of 19 or less) or have small body frames
tend to have a higher risk because they may have less bone
mass to draw from as they age.
Thyroid hormone. Too much thyroid hormone also can cause
bone loss. This can occur either because your thyroid is
overactive (hyperthyroidism) or because you take excess
amounts of thyroid hormone medication to treat an
underactive thyroid (hypothyroidism).
Medical conditions and procedures that affect bone health.
Stomach surgery (gastrectomy) and weight-loss surgery can
affect your body's ability to absorb calcium. So can conditions
such as Crohn's disease, celiac disease, hyperparathyroidism
and Cushing's disease — a rare disorder in which your adrenal
glands produce excessive corticosteroid hormones.
Low calcium intake. A lifelong lack of calcium plays a major
role in the development of osteoporosis. Low calcium intake
contributes to diminished bone density, early bone loss and an
increased risk of fractures.
Tobacco use. The exact role tobacco plays in osteoporosis isn't
clearly understood, but researchers do know that tobacco use
contributes to weak bones.
Eating disorders. Women and men with anorexia nervosa or
bulimia are at higher risk of lower bone density.
Sedentary lifestyle. People who spend a lot of time sitting
have a higher risk of osteoporosis than their more-active
counterparts. Any weight-bearing exercise is beneficial for
your bones, but walking, running, jumping, dancing and
weightlifting seem particularly helpful for creating healthy
bones.
Excessive alcohol consumption. Regular consumption of more
than two alcoholic drinks a day increases your risk of
osteoporosis, possibly because alcohol can interfere with the
body's ability to absorb calcium.
Corticosteroid medications. Long-term use of corticosteroid
medications, such as prednisone, cortisone, prednisolone and
dexamethasone, is damaging to bone. These medications are
common treatments for chronic conditions, such as asthma,
Arizona Science Center, azscience.org
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
rheumatoid arthritis and lupus, and you may not be able to
stop taking them to lessen your risk of osteoporosis. If you
need to take a steroid medication for long periods, your
doctor should monitor your bone density and recommend
other drugs to help prevent bone loss.
Other medications. Long-term use of aromatase inhibitors to
treat breast cancer, the antidepressant medications called
selective serotonin reuptake inhibitors (SSRIs), the cancer
treatment drug methotrexate, some anti-seizure medications,
the acid-blocking drugs called proton pump inhibitors and
aluminum-containing antacids are all associated with an
increased risk of osteoporosis.
Return to Table of Contents
Bone (bōn/): any of the pieces of hard, whitish tissue making up
the skeleton in humans and other vertebrates.
Bone Matrix (bōn/ /ˈmātriks/): The intercellular substance of
bone tissue consisting of collagen fibers, ground substance, and
inorganic bone salts.
Cartilage (ˈkärtl-ij/): a strong but flexible material found in some
parts of the body (such as the nose, the outer ear, and some
joints).
Cell (sel/): the smallest structural and functional unit of an
organism
Compact Bone (ˈkämˌpakt/ /bōn/ ): The part of the bone that is
smooth and very hard. It's the part you see when you look at a
skeleton.
Ligament (ˈligəmənt/): a tough piece of tissue in the body that
holds bones together.
Marrow (/ˈmarō/): a soft fatty substance in the cavities of bones,
in which blood cells are produced
Periosteum (perēˈästēəm): The outer surface of bone. It's a thin,
dense membrane that contains nerves and blood vessels that
nourish the bone.
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Experience more Busy Bones at our partner website Ask a Biologist:
http://askabiologist.asu.edu/busy-bones
http://depts.washington.edu/bonebio/bonAbout/bonAbout.html (All about bones)
http://depts.washington.edu/bonebio/ (Bone biology and games for kids)
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/B/Bone.html (Bone information)
http://www.lessonplanspage.com/SciencePEDemBonesNamingGameLesson45.htm# (Simon
says: Name that Bone lesson plan)
http://www.lessonsnips.com/docs/pdf/bonesbody.pdf (Bone reading activity with quiz)
http://www.discoveryeducation.com/teachers/free-lesson-plans/investigation-brokenbones.cfm
http://www.lawrencehallofscience.org/bigdinos/dino_ex1.pdf (Investigation: Broken bones)
http://www.brainpopjr.com/health/bodies/bones/grownups.weml (Bone lesson plan ideas)
http://www.webmd.com/a-to-z-guides/understanding-fractures-basic-information
(Understanding bone fractures: The basics)
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