Veterinary Medical Applications
Lesson Title: Musculoskeletal System
TEKS Addressed in Lesson:
130.6. (c)(6) all
Lesson Objectives:
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Understand the functions of the skeletal system
Understand the different uses of bones cartilage, ligaments and joints
Know the different parts of bones
Be able to show the difference in types of joints
Show knowledge of the three parts of a skeleton
Be able to label the bones of large animal structures such as Cattle, Horses, Swine, Sheep, Goats,
and Poultry
Be able to tell the difference in species based on differing skeletal features
Key Terms/Vocabulary
Abdominal obliques – large flat muscles that support digestive and reproductive organs
Abduction – movement away from the median plane
Adduction – movement towards the median plane
Agonist – prime mover of a joint
Ambulation – moving from one place to another
Antagonist – opposes movement of the agonist
Appendicular skeleton– consists of fore and hind limbs
Axial skeleton – consists of the skull and vertebrae
Biceps brachii – primary flexor of the elbow joint
Comminuted fracture – bone shatters into many pieces
Compound fracture – bone breaks through the skin
Deep digital flexor – primary flexor of the digit
Deltoid – primary abductor of shoulder
Diaphysis – body of a long bone
Endosteum – thin inner layer of bone covering; lines medullary cavity
Epiphysis – enlarged ends of long bones
Extension – moving the distal part of a limb away from the body
Fissure fracture – break along the long axis of a bone
Flat bone – plate of bone, i.e. scapula
Flexion – moving the distal part of a limb towards the body
Gluteals – large muscle of the upper hindquarters
Greenstick fracture – break on one side of a bone, usually due to a bending force
Irregular bone – complex and irregularly shaped bone, i.e. vertebrae
Latissimus dorsi – large dorsal muscle, attaches humerus to lumbar region
Long bone – bone longer than it is wide, i.e. humerus, radius, and femur
Masseter – muscle of the cheek
Medullary cavity – space within the bone filled with marrow
Metaphysis – joining point of epiphysis and diaphysis
Ossification – process by which tissue and cartilage becomes bone
Pectorals – primary adductors of the forelimbs
Periosteum – thin outer layer of bone covering
Serratus ventralis – attaches front leg to trunk
Sesamoid – small, seed-shaped bone embedded in a tendon, i.e. proximal and distal sesamoids
Short bone – cube shaped bone, i.e. bones of the carpus and tarsus
Simple fracture – bone does not break through the skin
Skeleton – framework of structures that support and protect the body
Synergist – muscle that indirectly aids the agonist
Synovial joint – freely moveable joint
Tendon – narrow band of tissue that connects muscle to bone
Transverse fracture – break completely across the bone
Trapezius – superficial triangular muscle of the shoulder
Triceps brachii – primary extensor of the elbow joint
Interest Approach/Anticipatory Set
Ask students to nod their head as if they are saying “yes” then shake their head as if to say “no.” Tell
them there are specialized bones in their neck that allow them to make these movements. Have
students flex their arms then straighten it out-this is called flexion and extension and it takes bones and
muscles to do this as well.
Ask students to “Think about how the physical structures of large livestock species differ from human
bodies. Based on this, how do you think their skeletons differ? What bones may they have or not have
that we do or don’t?” Discuss that most animals have tails and the bones in the tail are part of the
vertebrae, classified as the caudal vertebrae. Also discuss how most livestock have hooves rather than
fingers and toes. These are known as digits.”
Teaching Plan and Strategy Presentation of New Material
Students should follow along and take notes over PowerPoint Presentation. The “Musculoskeletal
System” covers information regarding the types of bones, the structure of bones, connective tissue as
well as joints.
The skeleton is a framework of structures, made of bones and cartilage that support and protect the
body.
Axial Skeleton- includes the skull, vertebrae, ribs, and sternum.
Appendicular Skeleton – the fore and hind limbs
Classification of Bones:
• Short bone – cube shaped, i.e. carpus and tarsus
• Flat bone – plate of bone, i.e. scapula, rib, skull
• Irregular bone – complex shaped, i.e. vertebrae
• Sesamoid – small, seed-shaped bone, i.e. proximal and distal sesamoids, patella
• Long bone – bone is longer that it is wide, i.e. femur, tibia, humerus, etc.
Bone Anatomy:
• Diaphysis – body of a long bone
• Epiphysis – enlarged ends of long bones
• Metaphysis – joining point of diaphysis and epiphysis
• Periosteum – thin outer protective layer of bone
• Medullary cavity – space within bone filled with marrow
• Endosteum – thin inner protective layer lining themedullary cavity
Bone Growth:
• Occurs in the epiphysis of long bones.
• Epiphyseal growth plates produce cartilage, which gradually turns into bone via a process called
ossification.
Fractures:
Major categories
• Simple – bone does not break skin.
• Compound – bone breaks through skin, much more serious.
• Complete – fracture goes completely across the bone.
• Incomplete – fracture does not go completely across bone.
Muscular System:
Muscles are a band or bundle of fibrous tissue in a human or animal body that has the ability to
contract, producing movement in or maintaining the position of parts of the body
Types of Muscle
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Skeletal muscle – allows for all voluntary movement, appears to be striated when looked at
under a microscope.
Cardiac muscle – controls the involuntary beating of the heart, appears striated under a
microscope.
Smooth muscle – responsible for all other involuntary movement, such as breathing, digestion,
peristalsis, blinking, etc.
Movement:
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Ambulation: moving from one place to another
Abduction: moving away from the median plane
Adduction: moving towards the median plane
Flexion: moving the distal part of the limb towards the body
Extension: moving the distal part of the limb away from the body
Muscle Function:
All muscles can do is CONTRACT or RELAX, so they generally work in pairs. For any particular action, the
muscles involved can be classified as:
Ex: for elbow flexion, the agonist is the bicep, and the antagonist is the tricep. For elbow extension, the
agonist is the tricep, and the antagonist is the bicep.
Identification of Major Muscles:
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Masseter – superficial muscle of the cheek
Trapezius – superficial triangular muscle of the shoulder
Latissimus dorsi – long, superficial, dorsal muscle that attaches the humerus to the lumbar
region of the back
Abdominal obliques – large flat muscles that support digestive and reproductive organs
Gluteals – large muscle of the upper hindquarters
Biceps femoris – lateral superficial muscle, one of three which forms the “hamstrings”
Biceps brachii – primary flexor of the elbow joint
Triceps brachii – primary extensor of the elbow joint
Pectorals – primary adductors of the forelimbs
Serratus ventralis – attaches forelimb to trunk
Activity/Application/Student Engagement/Laboratory
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Have students use the teacher presentation to label the skeletal system as well as the major
muscles.
Give students a variety of pasta and instruct them to build a replica of the skeletal system and
label each…they should also label the three sections of the skeleton (axial, and appendicular).
You can also have students color code or represent the joints, or other areas with colors or an
alternative label.
To review, project a large picture of a dog or cat skeletal system on the board, give students
strips of paper and have the tape the bone on the dog/cat in the appropriate area. These
handouts are included in the Cornell Curriculum.
Evaluation/Summary
Evaluation of student mastery can be concluded by written exam as well as from the activities listed
above.
Quiz and Key:
http://peer.tamu.edu/VBB/AgTeacherResources.asp
References/Additional Materials/Extended Learning Opportunities/Enrichment
Cornell Curriculum
http://peer.tamu.edu/VBB/AgTeacherResources.asp
http://cms.cnr.edu.bt/cms/files/docs/File/penjor/AAP/Skeletal%20system.pdf
College and Career Readiness Standards:
Science VI. A - G