In the photograph below, the heart and blood vessels of the neck region have been removed so that the trachea can be seen more clearly. The large hard structure attached to the trachea is the larynx.
The surrounding tissues have been separated to reveal the thyroid gland.Ĭontinue separating the tissue with a probe until the trachea and esophagus are exposed. The thyroid gland is darker and lies between the posterior ends of the two lobes of the thymus gland. Use a probe to separate the two lobes of the thymus gland and to further separate the musculature over the trachea. Use the probe to peel away muscle tissue until the thymus gland on each side of the trachea is exposed.
Fetal pig dissection diagrams digestive skin#
Hard palate, soft palate, glottis, epiglottis, and tongue.Ĭarefully, peel the skin away from the incision in the neck region using a blunt probe (a needle or the point of scissors will do if a blunt probe is not available). From the pharynx, it passes through the glottis to the trachea. The pharynx is the space in the posterior portion of the mouth that both food and air pass through. When breathing, air passes through the nasal passages to the pharynx. The hard palate and soft palate separate the nasal and oral cavities. The epiglottis projects up through the soft palate into a region called the nasopharynx. Open the jaw wide enough so that the glottis and epiglottis are exposed. You will need to cut through the musculature and the joint that holds the lower jaw to the skull. Use a scalpel to cut the sides of the mouth so that the bottom jaw can be opened for easier viewing (see figure 11). These two cuts will enable you to spread open the abdominal cavity. Figure 9.Ī cut is made on the side of the animal from the point just posterior to the diaphragm dorsally. Cut completely through the body wall in the abdominal area but keep the cut shallow in the neck region. Figure 8.Įxtend a single cut along the midline of the ventral surface of the animal to about 2 cm. The flap of body wall that contains the navel can be folded posteriorly to reveal the internal organs of the abdomen. Your finished cut will be anterior to the navel and along each side of the navel. Continue cutting from the anterior end of this cut so that it resembles an upside-down U. Insert one blade of scissors through the body wall on one side of the umbilical cord and cut posteriorly to the base of the leg as shown in figure 6. Tie one front leg of the animal with a string that passes underneath the dissecting pan to the other leg. Male: urogenital opening, penis, anus Preparation and Initial Cuts Female: genital papilla, urogenital opening, anus Figure 3. Female: injection site, nipples, umbilical cord Figure 2.
The word “urogenital” refers to an opening that serves both the urinary (excretory) and the reproductive systems. Use your pig and also a pig of the opposite sex to identify the structures in the photographs below. Obtain a fetal pig and identify the structures listed in figure 1. Use figures 1–4 below to identify its sex. The pig in figure 1 below has its ventral side up. The pig in figure 1 is lying on its dorsal side. If a structure is anterior to another, then it is closer to the head. The following words will be used to help identify the location of structures. Links to high-resolution, unlabeled photographs are also provided for many of the photographs. As a result, a structure shown in one photograph may look different than the same structure shown in another photograph.Ĭlick on any of the photographs to view enlargements. Several different pig dissections were used to obtain the photographs below. The incision can be seen in the first photograph below. An incision was made on the side of the neck to enable the injections.
The arteries have been filled with red latex and the veins with blue. Your grade on this laboratory will be assessed per the class participation (observed daily) with checkpoints evaluated.The fetal pig that you will dissect has been injected with a colored latex (rubber) compound.
0 kommentar(er)
