ANIMAL DISSECTION:

Frog

• Kingdom: Animalia
• Phylum: Chordata
• Class: Amphibia
• Order: Anura

Frog Characteristics

• Amphibians that live on both land and in/near fresh water such as ponds and rivers.
• Cold-blooded: uses sun and water to regulate body temperature
• Moist, permeable skin
• Carnivorous: feeds on earthworms, insects, spiders, and snails.

Untitled Slide

• Female frog lays eggs in water that are fertilized by the male frog.
• After 21 days the embryo becomes a tadpole with a tail and gills like a fish.
• At 5 weeks the tadpole grows legs, its mouth widens, it loses its gills and tail, and develops fully functioning lungs.
• A fully developed frog emerges from the water 11 weeks after egg was laid.

Untitled Slide

• Use pins to secure hands and legs to pan
• Use scapel to cut along the center and use picker to move skin aside
• Use scissors to make incisions along the center, across the top from left to right of the neck and lower abdomen, and up the center of the neck.
• Use picker to move the muscles aside to expose internal organs.

Untitled Slide

Rat

• Kingdom: Anamalia
• Phylum: Chordata
• Class: Mammalia
• Order: Rodentia

Rat Characteristics

• Thin-tailed, medium sized rodents
• The brown and house rat are the most common around the world because they hitched a ride in boats to every country
• Typically live where humans live
• Are prey to snakes, wildcats, and birds
• Most are nocturnal
• Omnivores that eat a mixture of plants and animals; known to eat most anything

Untitled Slide

• Placental mammals.
• Fast breeders and give birth to large litters of 6-10 babies.
• Can breed starting at 5 weeks of age.
• 22 day gestation period.

Untitled Slide

• Place pins in the hands and feet to secure them to the pan.
• Use scalpel to cut along the center and use picker to move skin aside.
• Use scissors to make incisions in muscle along the center, across the top from left to right of neck and lower abdomen.
• Lift the muscles using the picker to reveal the internal organs.

Untitled Slide

External Anatomy

• Both have a head, abdomen, 2 eyes, 4 legs
• Adult frog has no tail, rat has a tail. Frog has wet skin, rat is covered in fur. Frog has no external ears, rat has external ears.
• Both have fingers, but only rat has claws.
• Rat has teeth and wiskers

External Anatomy

EXTERNAL ANATOMY

Digestive system

• Both have an esophagus, stomach, small intestines, large intestines, liver
• Frog has a cloaca, a cavity at the end of digestive tract. Rat has an anus.
• Frog liver has 3 lobes, rat liver has 4 lobes.
• Rat has caecum, a dead-end pouch where the small intestine joins the large intestine.

Digestive system

digestive system

Respiratory system

• Both have a trachea, lungs, nostrils, and function of the respiratory system in both these animals is to supply the body with oxygen rich blood.
• Frogs have a moist skin though which diffusion occurs.
• Rat has diaphram, frog does not.
• Frogs have gills in tadpole state

respiratory system

respiratory system

cardiovascular system

• Both have 2 atria, 2 exits out of heart (1 going to the lungs and 1 going to the body), and a closed circulatory system.
• Frog has a 3 chambered heart, rat has a 4 chambered heart
• Frog heart has 1 ventricle, rat heart has 2 ventricles
• Blood vessels in frog are more visible through skin because it's ectothermic

cardiovascular system

cardiovascular system

Muscular System

• Both have muscles attached to their skeletons
• Frogs have stronger hind legs for leaping, and a strong jaw to clamp down on food
• Rat muscles work in groups moving together like human muscles, are very flexible, and they have 4 feet for fast movement to escape predators. When they move they expand their bones.

muscular system

MUSCULAR SYSTEM

MUSCULAR SYSTEM

MUSCULAR SYSTEM

MUSCULAR SYSTEM

Untitled Slide

• "Dissection Lab | Dissection Lab". Navteksolutions.Com, 2018, http://www.navteksolutions.com/store/shoppingcart/.
• "The Muscular System". Evolutionandbodysystem.Blogspot.Com, 2018, http://evolutionandbodysystem.blogspot.com/2013/05/the-muscular-system.html.

Untitled Slide

• "Vertebrate Comparitve Study". Jefsbio.Blogspot.Com, 2018, http://jefsbio.blogspot.com/2012/01/vertebrate-comparitve-study.html.
• Tratt, Adam. "Free Photos For All: How Haiku Deck Puts Creative Commons Images At Your Fingertips - Haiku Deck Blog". Haiku Deck Blog, 2018, https://www.haikudeck.com/blog/free-photos-