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#1 External Anatomy (Extra Credit)

Fetal Pig Dissection

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Our Fetal Pig

Cheek Key

1. Masseter

2. Facial Nerve

3. Sublingual gland

4. Submaxillary gland

5. Parotid gland

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Questions

Pig Lab #1 - External Anatomy
1. What is meant by gestation period?
2. What is the approximate age of your pig?
3. How many digits are present?
4. What differences can be observed in the structure of an artery and a vein?
5. How does a fetus get rid of its waste products?
6. What type of external features are used to separate mammals into orders?
7. Name the two external characteristics which distinguish mammals from other animals.
8. What goes in and out of the external nares?
9. What is another word for pinna? What is its function?
10. What is the function of the pig's vibrissae? Explain completely.
11. What is the function of the pig's nictitating membrane?
12. What is another name for the chest region of the pig?
13. What is another name for the "belly " region of the pig?
14. What is meant by urogenital openings?
15. Describe the major differences between a male and female pig's urogenital opening(s).
16. What does the urethral opening excrete in males? Females?
17. What is the vaginal orifice?
18. What does the scrotum contain?
19. Explain the difference between digitigrade, plantigrade, and unguligrade locomotion.
Which type is seen in pigs? Dogs? Deer? Humans?

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Answers

External Anatomy #1

  1.       The gestation period refers to the length of embryonic development of a fetus prior to birth.

  2.       The approximate age of the pig is 100 days.

  3.       Sixteen digits are present, four on each toe.

  4.       An artery is a reddish-pink color, a vein is a darker color. Arteries lead from the heart, veins lead to the heart.

  5.       A fetus gets rid of its waste products through the umbilical cord.

  6.       External features that are used to separate mammals into orders are method of movement and teeth.

  7.       The two external characteristics which distinguish mammals from other animals are hair during development and the females having mammary glands with openings to nourish their youth.

  8.       Moist and warm air goes in and out of the external nares.

  9.       Another word for pinna is auricle. The function is to catch noises for the eardrum.

  10.   The function of the pig’s vibrissae is to be a sensory facilitator, it helps the pig to feel its way around in the dark.

  11.   The function of the pig’s nictitating membrane is to protect the pig’s eye.

  12.   Another name for the chest region of the pig is the thorax.

  13.   Another name for the belly region of the pig is abdomen.

  14.   Urogenital openings are excretory openings of genetacia.

  15.   female - posterior to anus, male - posterior to umbilical cord

  16.   Female- Serves as the opening of the reproductive system and also the opening for urinary wastes to be excreted by the urethra

    Male- Is located posterior to the umbilical cord and serves as the opening of the reproductive system and as the opening for urinary wastes to be excreted by the urethra

  1. It refers to an aperture that is in a position both rear and posterior to the urethral opening.

  2. Scrotum, in the male reproductive system, a thin external sac of skin that is divided into two compartments; each compartment contains one of the two testes, the glands that produce sperm, and one of the epididymides, where the sperm is stored.

  3. The pigs and deers are unguligrade because they walk on their hooves. Humans are plantigrade because we walk on the entire soles of the foot. Dogs and cats are digitigrade because they walk on their digits.

Fetal Pig Lab Notes

·         Few hairs on nose and under chin

·         Female

·         Four toes per foot, 16 toes total

·         Four hooves

·         100 days old

·         23.2 cm

·         14 nipples

#1
#2

Oral Cavity

Questions

Pig Lab #2 - Oral Cavity
1. Why are the senses of taste and smell important to organisms?
2. Why do you think the incisors of rodents (such as mice and rats) are so large and never stop growing? Why
do pigs and humans not need these large incisors?
3. How does the tongue aid in eating?
4. How are the hard and soft palate indirectly used in digestion?
5. The hard palate separates the oral cavity from which other cavity?
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6. What is the function of the epiglottis?
7. What substances are secreted by the oral cavity of humans that aid in digestion? Name these substances
and tell what each does to help digestion.
8. The esophageal opening is the top of which tube? Where does this tube lead?

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Answers

Oral Cavity #2

  1. Taste focuses on sweet, salty, sour, bitter, or umami taste. Smell focuses on odors. Interactions between the senses of taste and smell enhance our perceptions of the foods we eat.

  2. They constantly chew other organisms so their teeth keep growing because they are constantly being filed down. Humans do not need large incisors because we are not carnivores and need large incisors to help “cut” our food. Our food is soft enough to be chewed and to be used with salivary glands.

  3. When you're ready to swallow, the tongue pushes a tiny bit of mushed-up food called a bolus toward the back of your throat and into the opening of your esophagus, the second part of the digestive tract.

  4. They help mechanical digestion so food can be better digested when swallowed.

  5. The oral cavity from the nasal cavity

  6.  The epiglottis is a leaf-shaped flap of cartilage located behind the tongue, at the top of the larynx, or voice box. The main function of the epiglottis is to seal off the windpipe during eating, so that food is not accidentally inhaled.

  7. What substances are secreted by the oral cavity of humans that aid in digestion? Name these substances and tell what each does to help digestion.

    Amylase - is an enzyme that catalyses the hydrolysis of starch into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion.

    Salivary Glands - produce saliva, which moistens the mouth to help chew and swallow food.

  8. Top of esophagus and leads to the stomach

Oral Cavity Key:

1. External Nostril

2. Oral Cavity

3. Hard Palate

4. Soft Plate

5. Oral pharynx

6. Nasal pharynx

7. Laryngeal pharynx

8. Esophagus

9. Epiglottis

10. Mandible

3

Digestive System

Questions

Pig Lab #3 - Digestive System
1. To what organ does the umbilical vein lead?
2. Describe the intestinal mesentery.
3. Where is the intestinal mesentery attached?
4. In humans, what structure is found at the junction of the small and large intestine?
5. What is the posterior opening of the digestive tract called? The anterior opening?
6. How many lobes (sections) does the liver have?
7. Where does the bile duct lead to and what substance does it carry?
8. List the function of each organ below:
a . stomach
b. esophagus
c. small intestine
d. large intestine
e. pancreas
f. liver
g. gall bladder
9. What structure separates the thoracic cavity from the abdominal cavity? Spasms of this muscle cause
what problem?
10. List two organs found in the thoracic cavity.
11. Describe the appearance of the inside of the stomach. How do the rugae within the stomach aid in
mechanical digestion?
12. How can you tell where the small intestine stops and the large intestine begins?
13. How do enzymes produced in the pancreas come in contact with food since food does not pass through the
pancreas?
14. What is an ulcer?
15. What is done in an appendectomy? Through which cavity does the surgeon enter?

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Answers

Digestive System #3

  1.       The umbilical vein leads to the liver.

  2.       The intestinal mesentery is a flap that holds the small intestine in place.

  3.       The intestinal mesentery is attached to the small intestine.

  4.       In humans the Ileocecal valve is found at the junction of the small and large intestine.

  5.       The posterior opening of the digestive tract is called rectum, the anterior opening of the digestive tract is called the mouth.

  6.       The liver has four lobes (sections).

  7.       The bile duct leads to the duodenum, it carries bile.

  8.        

a .Stomach: chemical/ mechanical digestion

b. Esophagus: peristalsis- moves food to stomach

c. Small intestine: nutrient absorption

d. Large intestine: water absorption

e. Pancreas: aids in digestion-enzymes for each macromolecule

f. Liver: destroy red blood cells, make bile, store glycogen; maintain glucose level

g. Gallbladder: store bile

  9.                  The diaphragm separates the thoracic cavity from the abdominal cavity. Spasms of the diaphragm cause hiccups.

  10.              Two organs found in the thoracic cavity are the heart and lungs.

  11              The inside of the stomach looks wrinkly because it will keep food close together withing the stomach for better digestion.

    How do the rugae within the stomach aid in mechanical digestion?

    It provides a rugged surface that helps further breakdown food

  12              You can tell where the small intestine stops and large intestine begins by looking at the cecum.

  13              Enzymes produced in the pancreas come in contact with food, even though food does not pass through the pancreas, because they are diffused across membranes and secreted into the small intestine.

  14             An ulcer is a sore that develops on the lining of the esophagus, stomach, or small intestine.

  15              An open appendectomy is the "traditional" way of removing an infected appendix. Basically, a surgeon makes an incision in the abdomen and locates the infected appendix. The appendix is cut away from the large intestine and removed from the body.

Digestive Key:

1. Trachea  2. Thyroid  3. Thymus  4. Left lung  5. Heart  6. Right pleural cavity                     7. Diaphragm  8. Peritoneal cavity  9. Spleen  10. Liver  11. Large intestine                           12. Small intestine  13. Gallbladder  14. Umbilical artery  15. Umbilical vein

4

Circulatory System

Questions

Pig Lab #4 - Circulatory System
1. What's the function of the thymus?
2. Which is larger, the right or left ventricle? Why?
3. Describe the difference between the right and left atria.
4. From what chamber does the pulmonary artery exit?
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5. From what chamber does the aorta originate?
6. To what structure do the pulmonary arteries lead?
7. What is the importance of the coronary circulation?
8. What problem results if coronary circulation is interrupted?
9. Why are arteries larger than veins?
10. What are the primary functions of the circulatory system?
11. Name the process that moves molecules from an area of high concentration to an area of low concentration.
In which type of blood vessel does this process occur? Why?
12. What is the function of heart valves?
13. In humans, what results when a valve is leaking blood backwards in the heart?
14. Why is it so difficult to get to the heart during open heart surgery?
15. Identify the body part(s) supplied by the artery or vein listed below:
a . hepatic artery
b. carotid artery
c. thoracic aorta
d. aorta
e. cranial vena cava
f. caudal vena cava
16. Explain in paragraph form the complete trip of a drop of blood through the heart and body. Start the trip
in the right atrium. Be sure to use the words below:
right atrium aorta a. v. valve
left atrium pulmonary arteries lungs
right ventricle pulmonary veins semilunar valve
left ventricle cranial (anterior) vena cava caudal (posterior) vena cava

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Answers

Circulatory System #4

  1.       Thymus - a lymphoid organ situated in the neck of vertebrates that produces T cells for the immune system

  2.       The left ventricle has a thicker muscle wall than the right ventricle. This is because the left ventricle has to pump blood all the way around the body, but the right ventricle only has to pump it to the lungs. The blood in arteries is under higher pressure than blood in the veins.

  3.       The right side of the heart then pumps this deoxygenated blood into the pulmonary veins around the lungs. There, fresh oxygen enters the bloodstream, and the blood moves to the left side of the heart, where it is then pumped to the rest of the body.

  4.       Blood flows from the right atrium to the right ventricle. The right ventricle, the right inferior portion of the heart, is the chamber from which the pulmonary artery carries blood to the lungs.

  5.       The aorta is the main artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries. The aorta distributes oxygenated blood to all parts of the body through the systemic circulation.

  6.       Once deoxygenated blood is pumped from the right atrium through the tricuspid valve into the right ventricle, contraction of the right ventricle will push blood through the pulmonic valve into the pulmonary artery that will carry deoxygenated blood to the lungs.

  7.       Coronary circulation is the circulation of blood in the blood vessels of the heart muscle (myocardium). The vessels that deliver oxygen-rich blood to the myocardium are the coronary arteries. The vessels that remove the deoxygenated blood from the heart muscle are known as cardiac veins.

  8.       Homeostasis is disrupted

  9.       Arteries experience a pressure wave as blood is pumped from the heart. This can be felt as a "pulse." Because of this pressure the walls of arteries are much thicker than those of veins. The vessel walls of veins are thinner than arteries and do not have as much tunica media.

  10.   The heart, blood and blood vessels work together to service the cells of the body. Using the network of arteries, veins and capillaries, blood carries carbon dioxide to the lungs (for exhalation) and picks up oxygen.

  11.   An area of high concentration to an area of low concentration is diffusion.  Capillaries are the smallest blood vessels and their walls are only one cell thick which allows diffusion between the blood and cells to occur. Nutrients and oxygen from the blood diffuses through the capillary walls into the tissues that need it.

  12.   The heart consists of four chambers, two atria (upper chambers) and two ventricles (lower chambers). There is a valve through which blood passes before leaving each chamber of the heart. The valves prevent the backward flow of blood. As the heart muscle contracts and relaxes, the valves open and shut, letting blood flow into the ventricles and atria at alternate times.

  13.   When the mitral valve is damaged-for example, by an infection-it may no longer close tightly. This lets blood leak backward, or regurgitate, into the upper chamber. Your heart has to work harder to pump this extra blood.Small leaks are usually not a problem. But more severe cases weaken the heart over time and can lead to heart failure.

  14.   They must cut through the sternum and reach between the lungs

  15.   Identify the body part(s) supplied by the artery or vein listed below:

a . hepatic artery - is a short blood vessel that supplies oxygenated blood to the liver, pylorus of the stomach, duodenum and pancreas.

b. carotid artery - The carotid arteries are major blood vessels in the neck that supply blood to the brain, neck, and face. There are two carotid arteries, one on the right and one on the left.

c. thoracic aorta - The thoracic aorta is a part of the aorta located in the thorax. It is a continuation of the descending aorta and contained in the posterior mediastinal cavity.

d. aorta - the main artery of the body, supplying oxygenated blood to the circulatory system

e. cranial vena cava - The superior vena cava is the large vein which returns blood to the heart from the head, neck and both upper limbs.

f. caudal vena cava - The inferior vena cava returns blood to the heart from the lower part of the body.

  16              Blood enters the right atrium from the superior and inferior venae cavae, and the coronary sinus. From right atrium, it goes through the tricuspid valve to the right ventricle. From the right ventricle, it goes through the pulmonary semilunar valves to the pulmonary trunk. From the pulmonary trunk it moves into the right and left pulmonary arteries to the lungs. From the lungs, oxygenated blood is returned to the heart through the pulmonary veins. From the pulmonary veins, blood flows into the left atrium. From the left atrium, blood flows through the bicuspid (mitral) valve into the left ventricle. From the left ventricle, it goes through the aortic semilunar valves into the ascending aorta. Blood is distributed to the rest of the body (systemic circulation) from the aorta.

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Questions

Pig Lab #5 - Respiratory System
1. Describe the exchange of gases in the lungs.
2. Explain (in paragraph form) the pathway of air from outside the body to the bloodstream. Be sure to use
the following words: nose, mouth, nasal cavity, lung, bronchi, trachea, alveoli, bronchioles.
3. Why is the trachea constructed with rings of cartilage?
4. What's the primary function of the respiratory system?
5. Why do you think the bronchi branch extensively into tiny air tubes?
6. Carbon dioxide is exhaled from the lungs. How is it produced?

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Answers

Respiratory System #5

1.      A being inhales O2 enters the lungs and reaches the alveoli. O2 passes through air-blood barrier into the blood in the capillaries. CO2 passes from the blood into the alveoli and is exhaled.

2.      Air enters the nostrils. It is moistened by mucus, warmed up to body temperature and dust is filtered out of the air, by hairs and trapped by mucus. It passes to the nasopharynx, to the oral pharynx. Next, it passes the glottis, to the trachea, or windpipe. Rings of cartilage support this breathing tube which leads to the right and left bronchi. These branch into each lung and further branch into smaller and smaller tubes. These are known as bronchioles. At the end of each bronchiole, is a cluster of air sacs or alveoli. Gas exchange occurs in the thin-walled alveoli which provide a huge surface area for the diffusion of oxygen from the alveoli into capillaries, so oxygen can be transported by the bloodstream to all the body's cells. Carbon dioxide diffuses from the capillaries surrounding the alveoli, into the alveoli, so it can be excreted when exhalation occurs.

3.      The trachea is constructed with rings of cartilage because it reinforces it so that it doesn’t collapse.

4.      The primary function of the respiratory system is to intake oxygen and release carbon-dioxide.

5.      The bronchi branch extensively into tiny air tubes to increase surface area.

6.      Carbon dioxide is exhaled from the lungs, it is produced by cellular respiration.

Respiratory System

6

Urogenital System

Questions

Pig Lab #6 - Urogenital System
1. What is the function of the kidneys? How many does the pig have? Where are they located?
2. What substances are carried in the urethra?
3. In which of the female's reproductive structures would embryonic or fetal pigs be found?
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4. List a function for each of the following and write whether each is a male or female structure.
a . ovary
b. testis
c. uterine horn
d. vagina
e. epididymis
f. urethra
5. Why is the scrotum important?
6. Which blood vessel - renal artery or renal vein - would have the cleanest blood? Why?
7. Kidneys are important organs. What helps to protect kidneys within the pig's body?
8. List a function for:
a . ureter
b. urinary bladder
c. urethra

 

Answers

Urogenital System #6

  1.       2 The fetal pig, as well as the born pig, has only two kidney. One kidney on its left, one on its right. the right kidney is a little lower than the left, behind the abdomen. The kidney in the fetal pig holds the urine, and has 2 main functions. The kidneys regulate the body's fluid volume, mineral composition and acidity by excreting and reabsorbing water and inorganic electrolytes. This helps balance these substances (which include sodium, potassium, chloride, calcium, magnesium, sulfate, phosphate and hydrogen) in the body and keep their normal concentrations in the extracellular fluid.

  2.       Liquid waste/ urine is carried in the urethra.

  3.       Between the stomach and small intestine

  4.       a . ovary - It is a female part. The ovaries have two main reproductive functions in the body. They produce oocytes (eggs) for fertilisation and they produce the reproductive hormones, estrogen and progesterone. ... In the ovary, all eggs are initially enclosed in a single layer of cells known as a follicle which supports the egg.

b. testis - It is a male part. The testes (plural) are the most essential organs of the male reproductive system. They are the glands where sperm and testosterone are produced. The testes are contained in the scrotum and are composed of dense connective tissue containing around three hundred internal compartments called lobules.

c. uterine horn - It is a female part. The uterine horns are the points where the uterus and the fallopian tubes meet. They are one of the points of attachment for the round ligament of uterus (the other being the mons pubis). ... The spare egg, that cannot travel the fallopian tube, is absorbed into the body.

d. vagina - Female part. The vagina receives the penis during sexual intercourse and also serves as a conduit for menstrual flow from the uterus. During childbirth, the baby passes through the vagina (birth canal). The hymen is a thin membrane of tissue that surrounds and narrows the vaginal opening.

e. epididymis - Male part. The epididymis is a long, coiled tube that stores sperm and transports it from the testes. It appears as a curved structure on the posterior (back) margin of each testis. It is comprised of three sections. These are the head, body, and tail.

f. Urethra - Female part. The urethra is the tube that carries urine from the bladder to outside of the body. In males, it has the additional function of ejaculating semen when the man reaches orgasm. When the penis is erect during sex, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.

  5                  The scrotum is the loose pouch-like sac of skin that hangs behind the penis. It contains the testicles (also called testes), as well as many nerves and blood vessels. The scrotum has a protective function and acts as a climate control system for the testes

  6                  The renal vein would have the cleanest blood because the kidney would have filtered out the poisons so the blood is clean.

  7                  Name for the fatty tissue that surrounds and protects the kidneys in pigs is called suet

  8                  a. ureter: The ureter is a tube that carries urine from the kidney to the urinary bladder. There are two ureters, one attached to each kidney. The upper half of the ureter is located in the abdomen and the lower half is located in the pelvic area. The ureter is about 10 to 12 inches long in the average adult.

    b. urinary bladder: The urinary bladder is a muscular sac in the pelvis, just above and behind the pubic bone. When empty, the bladder is about the size and shape of a pear. Urine is made in the kidneys, and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and voluntary.

    c. urethra: The urethra is the tube that carries urine from the bladder to outside of the body. In males, it has the additional function of ejaculating semen when the man reaches orgasm. When the penis is erect during sex, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.

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Nervous System

Questions

Pig Lab #7 - Nervous System
1. What is the function of the cranium?
2. Which lobes of the brain receive input from the nose?
3. What portion of the brain controls voluntary muscle movements?
4. What divides the cerebrum into a right and left hemisphere?
5. What is the role of the cerebellum in the body?
6. What part of the brain is the most posterior?
7. List a function for each of the following:
a . cerebrum
b. cerebellum
c. olfactory lobe
d. medulla oblongata
8. When a person suffers from a stroke, what happens?

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Answers

Nervous System #7

  1.       The function of the cranium is to house and protect the brain.

  2.       Olfactory Lobes receive input from the nose

  3.       The cerebellum is at the back of the brain, below the cerebrum. It's a lot smaller than the cerebrum at only 1/8 of its size. But it's a very important part of the brain. It controls balance, movement, and coordination

  4.       The longitudinal fissure divides the cerebrum into a right and left hemisphere.

  5.       The role of the cerebellum in the body is to receive information from the sensory systems.

  6.       The part of the brain that is most posterior is the cerebellum.

  7.       a . cerebrum: thought- language, voluntary

b. cerebellum: balance- involuntary

c. olfactory lobe: sense of smell

d. medulla oblongata: integration, regulation in cardiac, respiratory center

  8.   When a person suffers from a stroke, no oxygen can get to their brain

Extra Credit

Extra Credit (Heart & Brain)

Brain

Brain Key

1) Left Hemisphere

2) Right Hemisphere

3) Corpus Callosum

4) Brain Stem

Heart

Heart Key

1) Right Ventricle

2) Left Ventricle

3) Right Auricle

4) Left Auricle

5) Aorta

Created by: clayshia hill

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