Muscles Work in Pairs
• Muscles usually work in pairs. A good example of a pair of
muscles working together can be seen in the human arm.
The muscle at the front of the arm is called the biceps
muscle. The muscle at the back of the arm is called the
triceps muscle. When the biceps muscle is working
(contracted) the triceps muscle is relaxed. When the triceps
muscle is contracted the biceps muscle is relaxed. This is
called antagonistic action of muscles because they are
always working in opposite ways.
• Bell Ringer: 2-25-16
• Give 2 other examples of muscle pairs in the
body that work together to create movement.
Pre-Lab “What do you know?”
• What are three ways our bones allow us to
move? Hint (the 3 joints)
• What does a ligament connect?
• What does a tendon connect?
Pre-Lab “What do you know?”
Page 13: Chicken Wing Dissection
• What are three ways our bones allow us to
move? Hint (the 3 joints)
• What does a tendon connect?
• What does a ligament connect?
• What does cartilage do?
Muscles Work in Pairs
• Muscles usually work in pairs. A good example of a
pair of muscles working together can be seen in the
human arm.
• Bicep
• Tricep
• This is called antagonistic action of muscles because
they are always working in opposite ways
Muscles shorten and relax to move
bones
Tendons vs. Ligaments
What connects the muscle to the
bone?
What do ligaments do?
Ligaments are strong connective tissue that
holds bones together in moveable joints such
as the knee.
The anterior cruciate ligament (ACL) is a
ligament in the center of the knee that
prevents the shin bone (tibia) from moving
forward on the thigh bone (femur).
What does cartilage do?
Cartilage is connective tissue that is more flexible
than bone and it protects the ends of bones and
keeps them from rubbing together.
Torn meniscus or cartilage usually
requires knee surgery.
Definitions
Ligaments - strong connective tissue that holds
bones to bones
Tendons – connective tissue that connects
muscles to bones.
Cartilage – connective tissue that is more
flexible than bone. It protects the ends of bones
and keeps them from rubbing together.
Chicken Wing Dissection
• Problem: What are some characteristics of
skeletal muscles? How do skeletal muscles
work?
• Procedure:
1. Wear your apron, goggles and gloves at all
times.
2. Leave the chicken wing in the dissection tray
at all times.
Chicken Wing Dissection
3. Carefully extend the wing to find out how
many major parts is has. Draw a diagram of
the external structure in your comp. book.
Label the upper arm, elbow, lower arm and
hand (wing tip).
Chicken Wing Dissection
4. Use scissors to remove the skin. Cut only
through the skin. Caution: Cut away from
your body and your classmates.
Chicken Wing Dissection
5. Examine the muscles. Find the two groups of
muscles in the upper arm (bicep/tricep). Hold
the arm down at the shoulder, and alternately
pull on each muscle group. Observe what
happens. Label the bicep and tricep on your
drawing.
Chicken Wing Dissection
6. Find the two groups of muscles in the lower
arm. Hold down the arm at the elbow, and
alternately pull on each muscle group. Then,
make a diagram of the wing’s muscles.
Chicken Wing Dissection
7. Find the tendons – the shiny white tissue at
the ends of the muscles. Notice what parts
the tendons connect. Add the tendons to you
diagram.
Chicken Wing Dissection
8. A. Remove the muscles and tendons. Find
the ligaments, which are the whitish ribbonshaped structures between bones. Add them
to your diagram.
B. Find the cartilage at the ends of the bones.
The cartilage cushions the ends of the bones.
Add them to your diagram.
Ligament
Ligament
Bone marrow
Chicken Wing Dissection
9. Throw away all of the chicken parts and paper
towels into the large trash can in the back of
the room.
10. Your teacher will spray your table with
cleaner and you need to wipe it down.
11. Place the scissors into the tub of disinfectant
and
WASH YOUR HANDS WITH SOAP!!!
Chicken Wing Dissection
12. Make sure your diagram has the following
labeled:
-
Upper arm
Elbow
Lower arm
Hand
Bicep
Tricep
Tendon
Ligament
Cartilage
Post-Lab Quiz “What do you know?”
• Name 3 joints and where they are in the
human body.
• What does a ligament connect?
• What does a tendon connect?
• What does cartilage do?
• What are the 3 types of muscle?
Chicken Wing Dissection
13. Answer these post lab questions in your comp. book:
CSRQ the questions!
1. Were these muscles smooth, cardiac or skeletal?
2. Why must skeletal muscles work in pairs?
3. How are tendons and ligaments different?
4. When an athlete injures a ligament, why does it take
longer to recover from the injury than when an
athlete breaks a bone?
5. Where is smooth muscle found in the body?
6. Where is cardiac muscle found in the body?
7. Where is skeletal muscle found in the body?
8. How are your arm and a chicken wing similar and
different?