fetal pig dissection
TRANSCRIPT
Fetal Pig Dissection
Blood vessels in pigs were injected with a latex dye Arteries: Thicker, lead away from the heart
Veins: Thinner with valves, lead to the heart.
Pigs are mammals Mammary glands
Hair
Two distinct sexes
Similarities to humansPlacental
Tetrapods
Dissection Directional Terms
Anterior: towards the head end
Posterior: towards the hind end
Ventral: towards the belly
Dorsal: towards the back
External Anatomy
Compare forelimb to upper arm
Compare hindlimb to legs
Find umbilical cord
Both males and females have nipples
Look for hair
Identify as male or female
Oral Cavity and Pharynx
Oral cavity: tongue, teeth, and hard and soft palate
Pharynx: epiglottis, glottis, esophagus The jaw is opened wide enough so that the glottis and epiglottis are exposed. The epiglottis projects up through the soft palate into a region called nasopharynx. The hard palate and soft palate separate the nasal and oral cavities. When breathing, air passes through the nasal passages to the pharynx. The pharynx is the space in the posterior portion of the mouth that both food and air pass through. From the pharynx, it passes through the glottis to the trachea.
Neck region
Thymus, larynx, trachea, thyroid gland
A blunt probe is used to separate the two lobes of the thymus gland and to further separate the musculature over the trachea. The thyroid gland is darker and lies between the posterior ends of the two lobes of the thymus gland.
Thoracic Cavity
Identify heart in pleural cavity
Lungs and bronchi
Diaphragm separates from abdominal cavity
Abdominal Cavity
Identify heart, liver, lungs, small intestine, large intestine, diaphragm, urinary bladder, spleen, stomach
Food passes through the esophagus to the stomach, small intestine, and large intestine. The first part of the small intestine is the duodenum. Secretions released from the pancreas and gall bladder empty into the duodenum.
Excretory System
Identify bladder and kidney
The ureter carries urine from the kidney to the urinary bladder.
Male Pig Reproductive System
Female Pig Reproductive SystemThe urethra (carries urine from the bladder) merges with the vagina to form a common duct called the urogenital sinus.
Observe human model and compare to pig Cardiovascular
Respiratory
Digestive
Reproductive
Excretory
Respiratory System
Trachea: tube that brings air from mouth and nose
Bronchi: airways that branch going to each lung
Branch into bronchioles
Lungs: elastic breathing organs
Alveoli: thin, cup shaped membrane surrounded by capillaries
Location of gas exchange with the blood
Digestive SystemEsophagus: transports food to stomach
Stomach: muscular sac Mechanical and chemical digestion
Two sphincters control food entry and exit
Small intestine: digestionThree sections: duodenum, jejunum, and ileum
Large intestine: absorbs water, concentrates undigested materials
Liver: produces bile with digestive enzymes
Gallbladder: stores bile and releases into small intestines
Pancreas: secretes digestive enzymes
Digestive System