Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Sea Turtles
For example, Leatherbacks (one of the seven species of sea turtles on this earth) have a high concentration of red blood cells and their blood retains more oxygen. Their muscle cells have a high content of the oxygen-binding protein myoglobin. Myoglobin transports and stores oxygen in muscle tissue enabling them to dive underwater for long periods of time.
These majestic creatures of the sea are multicellular organisms and their cells are eukaryotic, meaning they're complex because of all the functions the cells must carry out to keep sea turtles alive and well. Their cells contain many of the same organelles as human cells: nucleus, mitochondria, ribosomes, cell membrane, etc. However, certain cells have certain functions.
Sea turtles have 7 main organ systems, similar to those of humans: skeletal, circulatory, respiratory, nervous, digestive, reproductive, and excretory. In fact all these systems are found in humans, but their functions in these turtles differs a little.
The respiratory system is extremely important to sea turtles as they are submerged in the water for a good amount of the time. They do breathe air, but in certain circumstances they must go to anaerobic metabolism for long periods of time. When surfacing to breathe, sea turtles can quickly refill their lungs with a single explosive exhalation and rapid inhalation. Their lungs have also adapted to avoid trapping gases during long dives.
The skeletal system of a sea turtle differs slightly from what we as humans are familiar with. A sea turtle has an exoskeleton and an endoskeleton. The exoskeleton is made up of the hard, bony shell surrounding the body like a shield. It gives them protection and also a place to hibernate in. The endoskeleton is made up of bones with spongy marrow inside. It also includes the typical bones to support the pedal like front limbs to swim and rear limbs to steer through water.
Reptiles became part of the evolutionary scene approximately 300 million years ago at the end of the Paleozoic Era. However, modern sea turtles have only been around for about the last 120 million years. During the Mesozoic Era, turtles went back and forth between land and sea many times. Thus, flippers and other sorts of evolutionary advantages didn't result until that time. The reptiles that faired the best during and after the mass extinction were perhaps the sea going turtles. Four families of sea turtles survived, Toxochelyidae, Protostegidae, Cheloniidae and Dermochelyidae. The former two families have since become extinct, Toxochelyidae during the Eocene epoch and Protostegidae during the Oligocene epoch. There are currently seven species of sea turtles swimming in the oceans.
Since there are seven different species of sea turtles, the ecological relationships differ for each species.
The Green Sea Turtles provide an example of mutualism when it comes to the patches of algae that cover their shells. Fish are able to feed off of the algae, in turn cleaning the shell of the turtle, a win-win situation for each species.
Sea turtles play a key role in their ecosystem in the ocean. They are one of the few organisms that feed off of sea grass which must be kept short since it is a breeding ground for fish and other marine life. If the sea grass becomes unhealthy for the sea turtle's lack of consuming it, then it would lead to a chain reaction decreasing the fish and other marine life population that rely on the sea grass.
In the circulatory system, a sea turtle's heart contains three chambers, which allows them to tolerate the carbon dioxide buildup in their bloodstream from infrequent respiration.
The biggest danger to sea turtles is humans. For centuries they have been hunted for their meat and their shells. The number of animal predators for sea turtles decreases as they get older and bigger. The new younglings are the one most commonly attacked. On land they may be consumed by foxes, dogs, birds, raccoons, crabs, lizards, and even dingos. In the water sea turtles have to worry about sharks and whales. While they do have protective shells, both sharks and whales can bite through them without any problem at all.
It is a myth that sea turtles can tuck their head inside their shells, only land turtles are able to do that!
Because sea turtles descended from land reptiles, they have evolved completely to become marine creatures. They adapted to the sea in order to survive as it was the best opportunity, and acquired many physical characteristics. Their forelimbs are modified into long, paddle-like flippers for swimming. Sea turtles can live in seawater with no need for a freshwater source. They obtain sufficient water from their diet and from metabolizing seawater. Many adaptations that make sea turtles successful in the sea actually make them slow and vulnerable on land.
Unlike Crush, the sea turtle in Finding Nemo that is 150 years old, most sea turtles generally live to be between 50 and 80 years old.
It is believed one method that males use
to see who should get to mate with the female is who
can raise their neck the highest. The female will choose
who she mates with.
Sea turtles live in almost every ocean throughout the world, nesting on tropical and subtropical beaches. They migrate long distances to feed, often swimming across entire oceans. They spend their entire lives at sea, except when adult females come ashore to lay eggs. Different types of adult sea turtles have different niches. For example, some occupy the niche of being grazers on seagrass, and others eat jellyfish. Young sea turtles have a different niche than adults. An example of this is the green sea turtle. Young green sea turtles eat small sea animals, but adults occupy the niche of seagrass grazers.