Download fetal pig dissection - lab # 3

FETAL PIG DISSECTION - LAB # 2
MUSCULAR SYSTEM TERMINOLOGY
1.
fascia(e) = sheet of connective tissue that encloses a muscle and appears white or shiny
2.
origin = The end of the muscle that is attached to a body part (usually skeletal) that is
normally held in a fixed position when the muscle contracts.
3.
insertion = The end of the muscle that is attached to a part of the body that is free to move.
4.
action = function of the muscle, how the muscle is used
5.
superficial = located near the surface (ex: epidermis = "superficial" layer of the skin)
6.
deep = describes more internal parts (ex: dermis = "deep" layer of the skin.)
7.
peripheral = outward or near the surface; This is used to describe the location of certain
blood vessels and nerves. For example, nerves that branch away from the brain
and spinal cord are called peripheral nerves.
8.
caudal = similar to posterior, toward the tail end
9.
cranial = similar to anterior, toward the head
10. medial = toward the center or midline of the body
HUMAN SKELETAL SYSTEM REFERENCE:
1.
sternum = breastbone
2.
midventral line = center of the body on the ventral side, runs from head to toe
3.
scapula = shoulder blade
4.
humerus = bone in upper arm (forelimb)
5.
femur = bone in upper leg (hind limb)
6.
tibia = larger of two bones in the lower leg
7.
hyoid = bone in throat region, below lower jaw and near base of tongue
8.
larynx = structure in throat region containing vocal cords, often called "voice box"
9.
thyroid cartilage = shield-like structure that covers part of larynx ("Adam's apple")
10.
digits = general term for both toes and fingers
11.
metatarsals = bones of foot between ankle and digits
12.
metacarpals = bones of the hand between the wrist and digits
13.
forearm = lower arm, between elbow and wrist
14.
phalanges = bones of fingers or toes
15.
vertebra(e) = the individual bones that together form the backbone
16.
pelvis = bones that form the hip
PIG SKELETAL SYSTEM REFERENCE:
1.
shank = lower part of hind leg
2.
forelimb = front leg
3.
hind limb = hind leg
FETAL PIG DISSECTION - LAB # 2
MUSCULAR SYSTEM
PSSA Standards for Reading, Writing, Speaking, Listening, Science and Technology
ASRWSL 1.1F = Understand the meaning of and apply key vocabulary across the various subject areas.
ASRWSL 1.2A = Read and understand essential content of informational texts and documents in all
academic areas.
ASRWSL 1.6A = Listen to others.
ASRWSL 1.6D = Contribute to discussions.
ASRWSL 1.6E = Participate in small and large group discussions and presentations.
ASST 3.2 C = Apply the elements of scientific inquiry to solve problems.
ASST 3.3 A = Explain the structural and functional similarities and differences found among living things.
ASST 3.7 A = Identify and safely use a variety of tools, basic machines, materials and techniques to solve
problems and answer questions.
MATERIALS: scalpel
Fetal Pig Reference Diagram Booklet
forceps (tweezers)
muscular terminology sheet
safety goggles / glasses
red and yellow colored pencils
pig
lead pencil
dissection pan lined with paper toweling
1 rough draft diagram entitled: SUPERFICIAL MUSCLES - VENTRAL VIEW
1 rough draft diagram entitled: SUPERFICIAL MUSCLES - LATERAL VIEW
GENERAL INFORMATION
Complete steps #1 through #4 below for each muscle listed in the directions. You are also going to
draw and label the femoral arteries and thymus glands. There are specific directions included in
the lab for each of these structures.
1). You are now going to locate and then draw several muscles and structures found in the fetal
pig. The directions for locating each muscle include a description of the muscle plus the origin
and insertion of the muscle (refer to “Muscular Terminology” page for definitions of these
words). The origin and insertion will help you find the beginning and end of each muscle.
2). A picture in the Reference Diagram Booklet is also listed for each muscle. The picture will
show you the general location of the muscle. Once you find the muscle, remove the fasciae
that surrounds it by gently scraping the muscle with the scalpel or pulling the fascia off with
the forceps. After the fascia is removed you can see the individual muscle fibers.
3). After you have located the muscle on the pig, draw it on the rough draft diagram making sure
that the muscle fibers run in the correct direction. Unless stated otherwise, draw the muscles
on both the left and right sides of the pig diagram.
4). Label each muscle by name on either the left or right side of the diagram. For the muscles that
are drawn on both the left and right sides, label only one of the muscles not both of them.
NOTE: There are areas on the prepared diagram sheets that will remain empty because you are
not going to locate all of the pig's muscles.
MUSCLE DISSECTION:
Begin by turning the pig so that the ventral side faces the ceiling. As you begin the muscle
dissection, use the rough draft diagram entitled: SUPERFICIAL MUSCLES - VENTRAL VIEW.
Thoracic Muscles (chest area):
REFER TO DIAGRAMS # 4 & # 6 in the Reference Diagram Booklet for muscles # 1 – 3.
1.
pectoralis major = This is a broad fan-shaped muscle. Draw the muscle only on the left
side of the diagram. You will add other muscles to the right side of the diagram later.
origin = the sternum
insertion = along almost the entire length
of the humerus
2.
pectoralis minor = The muscle is posterior to the pectoralis major. It also lies deep to the
pectoralis major. It extends from underneath the pectoralis major toward the midventral
line. Opaque, white fascia attached to the pectoralis major must be removed to see this
muscle.
origin = entire length of sternum
insertion = proximal end of humerus and
fascia covering supraspinatus (deep
shoulder muscle)
3.
external oblique = This muscle runs at an angle from the side of the body below the
forelimb, toward the umbilical cord.
origin = lower eight ribs
insertion = pelvic arch
Thigh Muscles:
REFER TO DIAGRAM # 4 of Reference Diagram Booklet for muscles #4 & 5.
These muscles are easier to observe if you flatten the hind leg so that the knee is parallel with
the dissection pan. There will be a lot of shiny fascia present, remove as much of it as possible.
4.
sartorius = The muscle is thin, triangular and located along the medial surface of the thigh.
It is usually ½” - 1" wide.
origin = pelvic region
insertion = proximal end of tibia
5.
gracilis = This muscle is a broad, thin muscle on the medial surface of the thigh. It is
caudal to the sartorius. It is the largest muscle of the thigh and extends toward the anus.
origin = pelvic region
insertion = same as sartorius
6.
femoral artery = You should be able to see the large "femoral artery" in each leg. If any
blood remains in the artery, it looks like a dark strand that runs between the gracilis and
sartorius, to the inner ankle bone. If blood is absent it will look like a piece of dental floss.
Draw an artery on each side of your diagram. Color them red and label one of them.
Throat / Neck / Shoulder Region:
REFER TO DIAGRAMS # 4 & # 5 in the Reference Diagram Booklet for muscles / structures
# 7 – 10.
As you locate and remove muscles in the throat region you will uncover some globular masses.
These are the thymus glands. In humans, they aid in the immune system. Do not remove these
glands. You are going to include them on your diagram.
7.
sternohyoid = This is composed of two long, flat muscles. They run side by side, along the
midventral line, from the chin toward the pectoralis major. Draw the sternohyoid muscle on
the left side of the diagram only. Leave the right side blank.
origin = anterior ribs
insertion = hyoid bone
8.
sternothyroid = There are two of these muscles. They run parallel and deep to the
sternohyoid muscles. To observe these you must remove the sternohyoid muscles carefully.
The sternothyroids can now be observed. They are narrower and shorter than the muscles
you just removed. If you press on the throat you can feel the hard covering of the larynx below
the sternothyroids. Draw the sternothyroid on the right side, in the blank space next to the
sternohyoid. You may have also uncovered and additional globular mass caudal to the
thymus glands. This is the thyroid gland. In humans it aids in the control of growth and
metabolism rates.
origin = sternum
insertion = thyroid cartilage (of larynx)
9.
sternomastoid = The muscles begin ventrally at the sternum. Then they separate into two and
each muscle extends laterally toward the back of the jaw. Both of them together form a "V"
shaped band. The muscles look like cords.
origin = sternum
insertion = left/right sides of skull, below ear
10. thymus glands = Draw and label the observable portions of the thymus glands. Outline them
in black and color them yellow.
Forelimb:
REFER TO DIAGRAM #11 in the Reference Diagram Booklet for the next two DEEP muscles.
Turn the Reference Diagram Booklet sideways so that the center of the book is horizontal. This is
a picture of the inside of the pig’s left forelimb (as you look at the diagram the forelimb is on your
right). Two blood vessels and a nerve are circled in the picture. Locate them and the pig’s elbow,
and use them as a point of reference. Muscle # 11 is above the circled blood vessels/nerve while
muscle # 12 is below them. Both are near the elbow.
11. biceps brachii = This is not a superficial muscle in the pig as it is in the human. To observe it,
you must first remove the right half of the pectoralis major and more fasciae. The muscle is
small, spindle-shaped and lies along the anterior surface of the humerus. Draw the muscle in
the blank area opposite your sketch of the pectoralis major. This is the only place you will
draw this muscle.
origin = shoulder region
insertion = lower forelimb
12. triceps brachii (medial head) = The triceps brachii is also deep to the pectoralis major. It is
larger than the biceps brachii. It also runs parallel and posterior to it. Draw the muscle in the
area opposite your sketch of the pectoralis major. This is the only place you will draw this
muscle.
origin = anterior end of humerus
insertion = lower forelimb
You have now finished the diagram named: SUPERFICIAL MUSCLES - VENTRAL VIEW.
STOP AND CHANGE DIAGRAMS
To finish the lab, use the diagram named: SUPERFICIAL MUSCLES - LATERAL VIEW.
From this point on you can only diagram the muscle on the pig's right side of the body.
Turn your pig on its side so that the snout is on the right (like the diagram).
Side of Face:
REFER TO DIAGRAM # 12 in the Reference Diagram Booklet for muscle # 13.
13. masseter = To locate this muscle, you must first skin the cheek of your pig. Uncover an area
that begins behind the mouth, continues below the eye, and ends in front of the ear. Be
careful not to damage the salivary glands (globular masses). The masseter is a large, round
muscle in the center of the cheek.
origin = skull region
insertion = lower jaw
Thoracic Muscles (back area):
REFER TO DIAGRAMS # 7 & # 8 in the Reference Diagram Booklet for muscles # 14 – 15.
14. spinotrapezius = This is a triangular shaped muscle that covers much of the dorsal thorax.
Turn your pig so that her / his dorsal side faces the ceiling and refer to DIAGRAM # 8. Locate
the entire muscle. Now return your pig to its lateral position and diagram only the portion of
the spinotrapezius that is visible from this view.
origin = scapula
insertion = proximal end of humerus
15. latissimus dorsi = This muscle is posterior to the spinotrapezius. It is broad and extends out
from under the forelimb. It covers a large portion of the dorsal, lateral and ventral sides of the
thoracic region. The muscle is also included on DIAGRAM #4.
origin = lumbar and thoracic
insertion = via tendon into proximal end of
vertebrae
humerus
Lower Forelimb:
REFER TO DIAGRAM # 10 in the Reference Diagram Booklet for muscles # 16 – 18.
On the lateral surface of the lower forelimb, there is a group of thin muscle bands that can be
separated and observed once the fascia is removed. Locate and draw only the following:
16. extensor carpi radialis
origin = distal portion of humerus
insertion = distal portion of lower foreleg
17. extensor digitorum lateralis
origin = same as extensor carpi radialis
insertion = digits
18. extensor carpi ulnaris
origin = same as extensor carpi radialis
insertion = metacarpals
Hip / Hind limb region:
REFER TO DIAGRAMS #7 & 9 in the Reference Diagram Booklet for # 19 – 23.
19. gluteus maximus = In humans, this muscle forms the primary tissue of the buttocks. In the pig
it is a small, triangular shaped muscle. It is close to the beginning of the tail.
origin = posterior vertebrae
insertion = fasciae latae
20. biceps femoris = A broad, thick muscle that covers most of the lateral surface of the thigh. It is
caudal / posterior to the gluteus maximus.
origin = pelvic region
insertion = distal end of femur
21. tibialis anterior = The most ventral muscle of the shank. It runs parallel with the "shin" up to
the knee.
origin = proximal end of shank
insertion = metatarsals
22 & 23. gastrocnemius & Achilles tendon = The gastrocnemius is the large muscle of the calf.
It runs into – and becomes – the Achilles tendon. The tendon passes into the heel and feels
like a cord running up the back of the leg if you pinch the pig directly above the heel. The
Achilles tendon is not a muscle and does not have fibers. Label both structures separately.
origin = distal end of femur
insertion = heel bone (calcaneous)
FETAL PIG DISSECTION LAB REPORT # 2 (95 points):
 THIS IS NOT A GROUP LAB REPORT. 
 EACH PERSON IN THE CLASS MUST TURN IN A LAB REPORT. 
There are two parts to this lab report:
I). two labeled diagrams of muscles
II). microviewer / microscope slide diagrams
An explanation of part I follows. The microviewer / microscope slide portion has a separate set of
instructions you will receive later.
I. Diagrams
Each person in the group must have two diagrams to turn in. Photocopies receive zero credit. The
diagrams are graded according to the following criteria:
location of muscle on the diagram
muscle fibers visible and running in the correct direction
neatness and correct spelling of labels
accuracy and legibility of labels
following the directions
1). Once you complete both rough draft pages, get a clean copy of each page to make your final
drafts.
2). Use either a black colored pencil or black pen to draw the muscle / muscle fibers
3). Use either a black colored pencil or black pen to label the muscles / structures.
4). Use either a black colored pencil or black pen and a ruler to draw lines from the labels to the
muscles / structures. The lines should not cross over each other.
5). Follow the specific instructions included in the lab directions for the femoral arteries (# 6) and
thymus glands (# 10).
FETAL PIG DISSECTION - LAB # 2
MUSCULAR SYSTEM
PART II – MICROVIEWER / MICROSCOPE SLIDE ASSIGNMENT
General Instructions
Use a lead pencil to draw and label the specimens. All the diagrams are to be colored.
Use the colors that you observe on the slides. Use a ruler to draw lines from the labels to the
structure or region on your diagram. The label lines should not cross over each other. The
assignment will be graded according to the following criteria:
A. accuracy and neatness of the diagram and labels
B. accuracy of the colors used
C. correct spelling and legibility of the labels
D. all labels on the right side of the circle
E. use of the ruler to draw the label lines / label lines are not crossed over each other
There are instructions provided for each slide. Please read the slide information BEFORE you
start the diagram.
MICROVIEWER SLIDE SET # 51 – ANIMAL TISSUES
You are going to diagram and label three of the microviewer slides. Please read the portion of the
slide cover that relates to the slide before you start.
SLIDE # 1 – VOLUNTARY MUSCLE CELLS
This is a section of skeletal (voluntary) muscle. The vertical strands that run from the top to the
bottom of the slide are the muscle fibers. There are many fibers on the slide. The alternate light
and dark purple horizontal stripes in each fiber are the striations. The darker horizontal stripes look
like dotted lines. They are the myosin filaments. The lighter horizontal stripes alternate with the
myosin filaments. The lighter horizontal stripes are the actin filaments. There are also many nuclei
visible. They look like oval dots on the fibers. One nucleus is labeled “A”.
Labels = skeletal muscle fiber
myosin filaments
actin filaments
nucleus
SLIDE # 2 – INVOLUNTARY (SMOOTH) MUSCLE CELLS
This is a section of smooth muscle. Many smooth muscle fibers are present. Each pink strand is
an involuntary muscle fiber. Notice that there aren’t any striations and the nuclei are visible but
pale in color. One fiber is labeled “A” and there are two oval nuclei near the letter “A”.
Labels = involuntary muscle fiber
nucleus
SLIDE # 3 – HEART MUSCLE
This is a section of cardiac muscle. It contains many vertical cardiac muscle fibers. These fibers
are striated but the striations are pale in color and not as obvious as in slide # 1. These fibers also
branch. This can be seen if you look at the letter “B”. The fiber branches to the left above the “B”
and toward the letter “A”. The other branch goes to the right. When you label the fiber branches
draw a line from the label to each branch. In cardiac muscle, where one fiber touches the next
fiber a junction is formed. The junction is called an intercalated disk. There are several of these
on the slide. They look like thin, dark stripes that go across the fiber (left to right). There is one
directly above the letter “C” and one in the fiber to the left of the letter “A”. Once you have located
these, the others become more obvious. The cardiac muscle fibers also contain visible nuclei.
Labels = cardiac muscle fiber
nucleus
fiber branches
intercalated disks
OVER
MICROSCOPE SLIDE – MOTOR NERVE ENDING
This is a section of skeletal muscle. The purple (or reddish pink) strands are the skeletal muscle
fibers. On some of the slides they are horizontal stripes, on other slides they are vertical stripes.
The striations in the muscle are pale in color and may not be visible. The thicker, black strand is
the nerve. The nerve branches are the smaller and thinner black strands that extend from the
nerve in several directions. Each nerve branch ends with an oval shaped structure that touches
the muscle fiber at the motor end plate. Remember that the motor end plate is the concave area of
sarcolemma where the nerve branch comes in contact with the muscle fiber. The oval end of the
nerve branch contains the vesicles that hold the acetylcholine and sits on top of the motor end
plate. The vesicles look like dark speckles inside the oval structure.
A). Place the slide in position and locate the specimen using the 10X eyepiece, 4X
objective and diaphragm setting #5. Adjust the focus and the slide until the specimen
is in the center of your field of vision and observed clearly.
B). Place the 10X objective in position, refocus and position the slide so that you can see
all of the structures.
Labels = nerve
nerve branch
skeletal muscle fiber
motor end plate
vesicles of nerve branch
FETAL PIG DISSECTION – LAB # 2
MUSCULAR SYSTEM
MICROVIEWER / MICROSCOPE SLIDE ASSIGNMENT
MICROVIEWER SLIDE # 1 – VOLUNTARY MUSCLE CELLS
MICROVIEWER SLIDE # 2 – INVOLUNTARY (SMOOTH) MUSCLE CELLS
FETAL PIG DISSECTION – LAB # 2
MICROVIEWER SLIDE # 3 – HEART MUSCLE
MICROSCOPE SLIDE – MOTOR NERVE ENDING
MUSCULAR SYSTEM