Lab 7 The Muscular System BIO201L
Student Name: Click here to enter text.
Access Code (located on the lid of your lab kit): Click here to enter text.
Pre-Lab Questions
1. How do banding patterns change when a muscle contracts?
The width of the pattern changes but the length does not. The degree of the
overlap also changes and leading to the shortening o the banding pattern.
2. What is the difference between a muscle organ, a muscle fiber,
myofibril and a myofilament?
Muscle organ is composed of numerous muscle fascicles, muscle fiber is an
elongated cell. Myofibril is composed of numerous myofilaments and they are
located in skeletal muscle cells and cardiac region. Myofilaments helps in the
structure of myofibril.
3. Outline the molecular mechanism for skeletal muscle contraction. At
what point is ATP used and why?
The sliding filament theory explains the skeletal muscle contraction. During
contraction, sarcomeres shorten with the actin and myosin sliding past each
other but remaining the same size.
4. Explain why rigor mortis occurs.
Rigor mortis occurs when the heart stops and leads to the lack of circulation
of blood and oxygen to vital areas. The lack of blood flow affects the
formation of ATP which is critical in myosin detaches from actin. The absence
of ATP conversion leads to muscle contraction since myosin and actin are not
separated.
Experiment 1: Tendons and Ligaments
Post-Lab Questions
1. Label the arrows in the slide images below based on your observations
from the experiment.
A- chondrocytes
B- collagen
C- collagen fibers
D- skeletal muscles
E- nuclei
F- collagen fibers
,Lab 7 The Muscular System BIO201L
, Lab 7 The Muscular System BIO201L
2. How does the extra cellular matrix of connective tissues
contribute to its function?
The extra cellular matrix helps to provide support and improves the
communication inside the tissue in the process of healing. The extra cellular
matrix of connective tissues increases the elasticity of the skin.
3. Why are tendons and ligament tissues difficult to heal?
There is lack of blood flow in these tissues.
4. What difference do you see between the tendon – muscle insertion
image and the tendon image?
The tendon imagery is more accurate as compared to the tendon-muscle
insertion. The tendon image has a more smooth finish to it with the tendon-
muscle insertion having uneven patterns of the connective tissues.
5. What differences do you see between the tendon and ligament sections?
The ligament fibers are denser than the tendon with the tendon displaying an
even shaped figure.
Student Name: Click here to enter text.
Access Code (located on the lid of your lab kit): Click here to enter text.
Pre-Lab Questions
1. How do banding patterns change when a muscle contracts?
The width of the pattern changes but the length does not. The degree of the
overlap also changes and leading to the shortening o the banding pattern.
2. What is the difference between a muscle organ, a muscle fiber,
myofibril and a myofilament?
Muscle organ is composed of numerous muscle fascicles, muscle fiber is an
elongated cell. Myofibril is composed of numerous myofilaments and they are
located in skeletal muscle cells and cardiac region. Myofilaments helps in the
structure of myofibril.
3. Outline the molecular mechanism for skeletal muscle contraction. At
what point is ATP used and why?
The sliding filament theory explains the skeletal muscle contraction. During
contraction, sarcomeres shorten with the actin and myosin sliding past each
other but remaining the same size.
4. Explain why rigor mortis occurs.
Rigor mortis occurs when the heart stops and leads to the lack of circulation
of blood and oxygen to vital areas. The lack of blood flow affects the
formation of ATP which is critical in myosin detaches from actin. The absence
of ATP conversion leads to muscle contraction since myosin and actin are not
separated.
Experiment 1: Tendons and Ligaments
Post-Lab Questions
1. Label the arrows in the slide images below based on your observations
from the experiment.
A- chondrocytes
B- collagen
C- collagen fibers
D- skeletal muscles
E- nuclei
F- collagen fibers
,Lab 7 The Muscular System BIO201L
, Lab 7 The Muscular System BIO201L
2. How does the extra cellular matrix of connective tissues
contribute to its function?
The extra cellular matrix helps to provide support and improves the
communication inside the tissue in the process of healing. The extra cellular
matrix of connective tissues increases the elasticity of the skin.
3. Why are tendons and ligament tissues difficult to heal?
There is lack of blood flow in these tissues.
4. What difference do you see between the tendon – muscle insertion
image and the tendon image?
The tendon imagery is more accurate as compared to the tendon-muscle
insertion. The tendon image has a more smooth finish to it with the tendon-
muscle insertion having uneven patterns of the connective tissues.
5. What differences do you see between the tendon and ligament sections?
The ligament fibers are denser than the tendon with the tendon displaying an
even shaped figure.
