Frog Dissection Essay

Submitted By kylee47
Words: 4520
Pages: 19
Open Document
NAME: LIM WEI LING
STUDENT ID: 19164548 6 MAY 2004
LAB SESSION: WEDNESDAY, 9-12 A.M. LAB 8

VERTEBRATE STRUCTURE AND FUNCTION
DISSSECTION OF THE FROG
INTRODUCTION
The vertebrates are part of a phylogenetic branch of the animal kingdom. Mammals, birds, snakes, turtles, amphibians and various classes of fishes are all examples of vertebrates. In this experiment, the representative vertebrate used for dissection is the frog. Frogs belong to the Class Amphibia, order Anura. Adult frogs lack tail and caudal (tail) vertebrate are fused into a rodlike structure called urostyle. Most amphibians divides their lives between fresh water and land, thus are abundant in damp habitats such as swamps and rainforests. Hence, their body systems show adaptation to both aquatic and terrestrial environment. They rely heavily on their moist skin to carry out gas exchange with the environment. Besides that, the skin of frog functions in temperature regulation and absorption and regulation of water. On land, frogs use heir powerful hindlegs to hop along the terrain. It nabs its prey by flicking out its sticky tongue, which is attached to the front of the mouth. Besides that, frog also displays a wide variety of adaptations that help them avoid being eaten by larger predators. The skin gland of frog secretes poisonous mucus. Many poisonous frog species have bright colouration that apparently warns predators. Many frogs also exhibit colour patterns that camouflage (Campbell & Reece, 2002; Harley & Miller, 1992). With reference to the metamorphosis of frogs, amphibians indicate two lives. The larvae stage of a frog is a tadpole. The tadpole is usually an aquatic herbivore with gills, a lateral line system resembling that of fishes and well-developed tail. The tadpole thus lacks legs and swims. As the tadpole develops, the gills and the lateral system disappear and the legs develop. In the adult frog, air-breathing lungs, pairs of external eardrums, and a digestive system are developed to adapt to the terrestrial environment (Campbell & Reece, 2002). Frogs generally lay their eggs in ponds and swamps or at least in moist environments. Amphibian eggs lack shells and dehydrate quickly in dry air. Hence, reproduction of frog is tied to the water. Frogs reproduce through external fertilisation, with the male grasping the female and spiling the sperm over the eggs as the female sheds them. There are also some ovoviviparous and viviparous species that retain the eggs in the female reproduction tract, where embryos can develop without drying out (Campbell & Reece, 2002). In this experiment, the digestive system and the nervous system of the frog is examined to understand he vertebrate structure and function. Frogs although are amphibians posses all the essential features of vertebrates. Hence, frog is used for dissection to observe and understand the vertebrate structure and function.

AIM
To understand and develop the skills in the techniques and terms associated with dissection of a vertebrate, give a frog as a representative
To identify the anatomical structures and understand their relationship
To relate the structures and function of the body system in verterbrate

MATERIALS female frog - scissors wax dissecting tray - scalpel dissecting pins - forceps

EXPERIMENTAL PROCEDURES
Examination of External Features The skin colour and texture of the frog provided was observed. The parotid glands were located. The external nares (nostrils) were observed and the eyes were located laterally on the head. The eyelids were gently opened with a probe to locate the nictitating membrane. Laterally n the head, and slightly posterior to the eyes, the tympanic membrane, which was the external detector of the frog hearing system was located and observed. The hindlegs and forelegs of the frog were examined. The length and musculature of each was compared and their functions were
Show More

Related Documents: Frog Dissection Essay

The Pros And Cons Of Dissection

Others argue that dissection causes more harm than good, and being as there are numerous alternatives, there is no reason for forcing students to dissect. Ways for students to learn about anatomy and physiology without using animals that have been killed have been created. The world has advanced in ways where death for dissection can be prevented while still being able to get the full experience: “Virtual dissection simulations, 3D models, plastinated specimens, videos, slides, charts, and online…

Words 529 - Pages 3

Bullfrog Lab

large. A bullfrog's diet ranges from worms, insects, crayfish, fishes, other frogs, snakes, turtles, small mammals and even some birds, therefore this diet insinuates towards being carnivorous. There is another vertebra that is found in various places around the…

Words 1023 - Pages 5

Animal Testing Research Paper

over one hundred million deaths every year. These animals include, but are not limited to, mice, rats, cats, dogs, frogs, rabbits, hamsters, guinea pigs, monkeys, fish, and birds. The list of animals being tested could go on forever. They are killed from experimentation in laboratories for medical research, or chemical, drug, food, and cosmetic testing, biology lessons such as dissection, and some people just use animals for their curiosity driven experiments. People started testing on animals back…

Words 1177 - Pages 5

Essay Oryx and Crake

Should Morality Limit Scientific Progress When I was in Grade 10, I did a dissection for the first time in my life and I found myself feeling really uncomfortable. The frog my group members and I dissected was female, and also pregnant. When we laid the frog on her back and spread her legs wide, when we pinned the needles through her feet, when we used cold scissors to open her belly and took the eggs out of her womb, I felt nauseated and depressed. I felt like I had done something wrong. I felt…

Words 622 - Pages 3

Pig Dissection Reflection

Anticipate While Dissecting Fetal Pigs I have performed many dissections in the past including a rat, a frog, worms, and a fetal pig (in fifth grade!). However, because I have not done a dissection in a long time, I won’t be familiar with the tools. There will probably be a learning curve. We haven’t studied anatomy much this year (although I did study all of the organ systems a lot in preparation for the AP test) so I think this dissection will be very helpful in understanding pig, mammalian, and…

Words 883 - Pages 4

Animal Testing Research Paper

The use of animals for testing products from common household items to new medicine has been considered the best way to see if a product is safe for human use. Each year, more than 100 million animals-including mice, dogs, cats, rabbits, and many more are hurt, tested and killed in the U.S. alone. In the name of science by educational institutions, household products, cosmetic companies, and many more. There are billions of animals that have suffered a vicious, painful death in the name of research…

Words 701 - Pages 3

Animal endangerment2 Essay

between 4-6 months of age, while they could reach 15 years. Argument 3 WHAT’S WRONG WITH DISSECTION? EVERY animal used for classroom dissection was once alive and didn’t want to die. I mean, come on! Would you want to end up on a dissection tray for a classroom experiment? Many of these animals suffer greatly before being shipped to schools and used in a school lesson. Every year, millions of frogs are taken from their homes in the wild. Homeless, lost, and abandoned cats are often collected…

Words 788 - Pages 4

Bulls: Rana and Bullfrogs Essay

an aquatic frog, a member of the family Ranidae, or “true frogs”. This species has traditionally been classified as Rana catesbeiana, but there is some dispute as to whether Lithobates catesbeianus is a more correct name. This frog inhabits large, permanent water bodies, such as swamps, ponds, and lakes, where it is usually found along the water's edge. The male bullfrog defends a territory during the breeding season. His call is reminiscent of the roar of a bull, which gives the frog its common…

Words 3159 - Pages 13

Finch Lab Essay

Name:_____________________________Period:___ Dissection Partners’ Names: ______________________________________________ General Overview: We will spend the rest of the semester on our animal dissections. First, you will dissect the earthworm and crayfish to allow you to examine two invertebrate species. Then, your lab group of 4 students will spend 4-5 days identifying parts of the fetal pig and participating in a comparative vertebrate dissection where your group will be the “expert” on one…

Words 3071 - Pages 13

Essay Andreas Vesalius History Homework 2

in the septum of the heart. He also said that blood was continually being made up to make up for the fact that it was used up by the body. 8. What ideas were important to Harvey? The ideas that were important to Harvey were: Careful observation Dissection Experiment in order to improve his knowledge of how the body worked 9. What idea did Harvey begin to work on in 1615? In 1615, Harvey began to work on the idea that blood circulated around the body. 10. What new invention helped Harvey, and…

Words 1842 - Pages 8