Skeletal System

Bell Work
• The body system responsible for breaking
down food into nutrients the body can use
is the:
• A. nervous system
• B. reproductive system
• C. digestive system
• D. integumentary system
Need to Know
• Read the article, “Some of Chocolate’s
Health Benefits…” Then explain two of the
benefits of the bacteria in our guts. Use
complete sentences and cite evidence
from the text to explain your answer.
• Can I explain the basic functions of a
major organ system? (SPI0707.1.3)
Skeletal and Muscular Systems (one page)
Skeletal System (pg. 210-213)
Bones, cartilage, and the connective
tissue that holds bones together make up
the skeletal system.
Functions of the skeleton:
Storage (minerals and fats)
Blood cell formation
Skeletal System
Stiff, flexible
connective tissue
- red bond marrow (new red blood cells, white
blood cells, & platelets are made); yellow bone
marrow (made mostly of fat)
- very strong; supports body; makes up 80%
of the bone
- full of pores, which are filled with marrow, nerves, and
blood vessels that carry cells and nutrients in and out of
the bone.
Skeletal System (pg. 210-213)
A place where two or more bones meet
is called a joint.
Three Joints:
1. Gliding Joint = hand & wrist
2. Ball-and-Socket Joint = shoulder
3. Hinge Joint = knee
Joints are held together by ligaments.
Ligaments are strong elastic bands of
connective tissue.
• BrainPop Skeletal System
• BrainPop Joints
Muscular System (pg. 214-217)
The muscular system is made up of muscles
that let you move.
Three kinds of muscles:
1. Skeletal- enables bones to move (attached to bones)
2. Smooth- moves food through the digestive system
3. Cardiac (heart)- pumps blood
Muscular System (pg. 214-217)
Strands of tough connective tissue called
tendons connect your skeletal muscles to
Muscles work in pairs:
1. Flexor (biceps)- a muscle that bends part of
the body.
2. Extensor (triceps)- a muscle that straightens
part of your body.
• For each body system, draw and color at
least one organ that belongs in that body
• For example:
– Skeletal System = bones or the skeletal
– Muscular System = one or all of the three
types of muscles (skeletal, cardiac, smooth)
• Use your textbook pictures or the sample
sheet in the folder at your group.
Interesting Facts
Skeletal System:
• The longest bone is the 'femur',
in the thigh. It makes up almost
one quarter of the body's total
• The smallest bone is the 'stirrup',
deep in the ear. It is hardly larger
than a grain of rice.
• The ears and end of the nose do
not have bones inside them, they
are made of cartilage.
• After death, cartilage rots faster
than bone. This is why the skulls
of skeletons have no nose or
• Newborn babies are actually
born with many more bones than
adults (around 300), but many
bones grow together, or fuse, as
babies become older.
Muscular System:
• There are about 60 muscles in
the face. Smiling is easier than
frowning. It takes 20 muscles
to smile and over 40 to frown.
• The smallest muscle in the
body is the stapedius, deep in
the ear. It is only 5mm long
and thinner than cotton thread.
It is involved in hearing.
• The biggest muscle in the
body is the gluteus maximus,
in the buttock.
• When building muscle,
damage occurs within the
muscle fibers in the form of
tears. Your body will then
repair this damage during your
recovery periods. Additional
tissue forms around the site of
the injury, increasing the size
of your muscles.
Human Body Systems Pictures
Human Body Books