The Asteroidea class, also known as the sea stars, has many common characteristics. Firstly, all sea stars have flat, star-shaped bodies as well as a central disc with radiating arms/rays protruding out. Typically, seastars has five arms but certain species can have up to fifty arms! The size of the sea stars is not consistent through the different species therefore varies from one centimeter to three feet. The skeletal system is a key aspect for the survival of a sea stars. Sea stars have bilateral symmetry. The skeleton is made up of ossicles which helps make for flexibility yet firm enough to hold together. Their flexibility enables them to catch prey easily and sufficiently. The spine and pedicellariae is small and movable. On the upper
This laboratory experiment involving invertebrates is conducted to enable students to investigate Daphnia magna’s responses to external stimuli, therefore developing a better understanding and knowledge of homeostasis that occurs in organisms and the reaction and behavior exhibited by the daphnia magna when varying conditions are exposed to the organism compared to its natural environment conditions (Carter-Edwards et al, 2011). In order to understand the experiment, a foundation of information about the chosen organism such as its natural environment and physiology must be understood.
The purpose of this study is to understand the feeding rate of Daphnia magna. D. magna is a species of Daphnia that belongs to the suborder Cladocera (Ebert, 2005). They live in freshwater and feed on small, suspended particles in the surrounding water. They are filter feeders. Leaf-like appendages, called phyllopods provide a filtering apparatus for the collection of food. These structures beat to produce a constant current of water, allowing particles to be filtered by fine setae on the thoracic legs. The particles are then transferred to their mouth groove to be ingested. D. magna typically feed on planktonic algae (Ebert, 2005). The following experiment uses algae to test what affects the feeding rate of D. magna. The rate of filtration
This lab investigated how differing conditions in water would affect the reflex known as the dive reflex, which was evaluated by measuring heart rate and amplitude of blood flow. The dive reflex is explained as a drop in heart rate and blood flow while the subject is submerged underwater. Bradycardia is the term used to describe the decreased heart rate (HR), and it is advantageous to mammals. Bradycardia helps retain as much oxygen as possible during the submersion in order for muscles to work more effectively. A normal heart rate is 60-100 beats per minute (BPM). Decreased blood flow (BF) is due to vasoconstriction (constriction of vessels) and this benefits mammals by regulating body temperature while underwater (thermoregulation). Thermoregulation
After effectively conducting the experiment, the results acquired clearly shows the impacts of the variables applied and materials used to create a stimulus on the daphnia which can be seen with changes in its movement behavior and heart rate. With a certain level of knowledge in biology, some of the results and responses obtained were as expected, corresponding to the changes inflicted on the daphnias.
Chitons are a class of mollusc called Polyplacophora, when examined, share the same anatomical features as those of the first molluscs on earth. This means that they are t closely related to the beginning of the mollusc group. These molluscs vary in size but have the same features as a long, oval flat body with a segmented mantle to protect the ventral of the chiton. These organism have learned to create a “suction” affect using their ventral to hold on to rocks so that they do not get washed away by the waves. Their radula is a teeth like structure that scrapes of algae that are living on rocks. Chitons also have light sensitive receptors that will detect an amount of light that might be harmful to them and move slowly to the shade using their
Tardigrada, aka the Tardigrade is potentially the toughest animal on earth. They can be found almost anywhere - the top of the himalayas, japanese hot springs, deep ocean trenches, from polar regions to the equator. They make their homes in dunes, beaches, soil, lichens, mosses and marine and freshwater sediments. These tiny 1mm long extremophiles have been found to withstand the pressures of the deepest ocean trenches, mass amounts of radiation, and being heated to 150 degrees fahrenheit to being frozen to near absolute zero.
Initially thought to be a virtue, Oedipus' pride and confidence began to build his blind ego. This changed his tragic flaw from a virtue to a burden. His early successes created a sense of pride and blind confidence. But it was this excessive pride that would pride that lead to early successes but ultimately created a clouded sense of reality and his ultimate demise. As the curse is upon the city, Oedipus thinks he is the one to find the killer of the previous King of Thebes. Without realizing that his father was the king before him and that his father is the one he killed many years before, he openly promises to bring the murderer to justice. He is hinted many warnings from the gods and Terisias, the blind prophet, but ignores them because
The hummingbirds are unique birds. They are small and extremely lightweight, exhibit exceptionally high metabolism rates, and possess the multi-directional flying ability. Hummingbirds are some of the smallest birds. The species Bee hummingbird is the tiniest of all birds weighing less than 2 g (0.07 Oz). Insects excepted, the hummingbirds have the
Introduction: Invertebrate animals which belong to mollusks which means “head foot” and characterized by large head and modified feet. This group includes octopuses, squid, cuttlefish and nautiluses. Members of cephalopods are characterized by their ability to quick change their color as well as changing the texture and shape of their bodies as a means of camouflage.