G Setosus Lab Report

The squid and octopus are both cephalopods with eight “arms,” known as head-footed animals. Although they share several similarities at first glance, their physicalities are very different. Where squids possess a pen (a stiff sort of backbone) with two fins on it, the

often will people think of a nautilus, an organism that is a distant cousin of cuttlefish and squid. These organisms have been dubbed "living fossils" and have been on earth for about 500 million years. The nautilus tends to in front of coral reefs, deep in the ocean. The long existence of the nautilus has allowed its mesmerizing spiral shell to be embedded in some rocks and has become a part of the fossil record.

The Deep sea ecosystem has been classified as the largest ecosystem compared to all other ecosystems within the world (Martin, 2003). The main characteristics of this ecosystem is that it experiences very low oxygen levels, the water temperature is extremely cold, the pressure within this area is very high and sunlight do not penetrate to these depths. The species that do live within this environment are highly adapted to these harsh conditions such as the Cookie-cutter Shark (Isistius brasiliensis) (Figure 02). This essay will mainly focus on the Cookie-cutter Shark as well as

The ganglion and the two nerve cords that run along either side of the planaria are connected and are all used in the process of sensing stimuli that occur in the animal’s surrounding. Running back and forth from the organism’s sides are transverse nerve cords; each of these cords connect to the two lateral nerve cords at commissures. By observing the two nerve cords and the many transverse nerve cords, the Dugesia tigrina’s nervous system appears similar to a ladder (Miller 2007).

This small creature requires extraordinary effort to keep it alive in captivity. The researchers who are studying the creature have discovered certain peculiarities about the octopus, such as an inability to

Dugesia spp., also known as planaria is a small flat dark brown worm of varying sizes around 0.3 – 2 cm long and 1 – 2 mm wide (Palmer and Fowler, 1975 as cited by Cha, 2001). Although they are small, they are hermaphroditic (Maule, 2006). The middle of the body is darker in color with tiny spots. The body consists of an arrow shaped head and a long unsegmented body that narrows as it reaches the posterior end (T. Huang, biology student, personal communications). Midway down the ventral side of its body, the pharynx is a tube-like structure that protrudes out for feeding (Cha, 2001). The body is smooth and stretches in contracting and expanding movements as the Dugesia spp. travels around a flat surface (T. Huang, biology student, personal communications). The two side parts of the arrow that extends out of its head are sensory organs, the auricles (Cha, 2001). The auricles help sense water currents so that the Dugesia spp. is aware of the direction of water flow (Kriska and Gyorgy, 2013). Dugesia spp. has tiny eyes called eyespots located on the dorsal side of its arrow head. The eyespots can detect light and are extremely sensitive to light (Cha, 2001).

Like all other brachiopods Neospirifer were an exclusively marine fauna. Neospirifer have been found throughout many shallow shelf environments from the Carboniferous and Permian periods. In their adult forms they were attached to the substrate by a fleshy pedicle extending from the larger or ventral valve making them epifaunal and sessile organisms (Kaesler, 2006). The two valves were opened and closed through the use of internal muscles while teeth and sockets held the valves closed. Unlike bivalves brachiopod valves are not symmetrical and show bilateral symmetry (figure 2).

The Pterois volitans, also known as the lionfish, is a remarkable creature that possesses adaptations, such as venomous tentacles, striping for camouflage, and control over its center of gravity, that makes for an enduring species. These beautiful fish can be found in warm marine reefs and coral from the Great Barrier Reef of Australia to the coasts of Florida and North Carolina. Moreover, these fish thrive in temperatures ranging from 60oF to 90oF. While lionfish are usually found in shallow waters, some are reported as living 175 feet deep. The lionfish has acquired adaptations to improve the chances of survival and fitness in an aquatic habitat. One such adaptation is the red, white and black striping that covers the lionfish’s body. Reefs

Rocky shore habitats are biologically rich ecosystems owing to diverse niches those offer shelter to wide array of inter-tidal and estuarine organisms (Nybakken and Bertness, 2005). Brachyuran crabs are one of the most common organisms those bring about coupling between herbivores and higher level carnivores, and also enable regeneration of nutrients through scavenging (Boudreau and Worm, 2012). The crabs inhabiting rocky shores mainly belong to families Xanthidae, Oziidae, Pilumnidae, Portunidae, Grapsidae and Sesarmidae.

There has been studies done that focus on the reproductive morphology, mating behavior, and spawning ecology of two types of cephalaspid sea slugs (Aglajidae and Gastropteridae). There had been experiments done of four opisthobranch species that belong to the families of Aglajidae and Gastropteridae. Behavioral and morphological traits vary considerably between species, even closely related sister taxas. Also while they observed the species from each group

The phylum of Orca Whales are Chordata. The subphylum is vertebrata. Animals of the Chordata family have four key features: notochord, dorsal hollow nerve cord, pharyngeal slits, and post-anal tail. Notochords are a flexible rod-shaped structure that is found in the embryonic stage of development along in the adult stage of some chordate species. This feature is located within the digestive tube and the nerve cord; it provides skeletal support through the length of the body. The dorsal hollow nerve cord comes from the ectoderm that rolls into a hollow tube during the development stage. The ectoderm is an outer layer of three tissues within the embryo that produces the epidermis and nervous system. This feature is usually located dorsally near

Different statistics have been calculated revealing the extent of mixotrophs in the environment and their resulting effect on the food web. A study by Dolan and Pérez found that mixotrophs represent “on average about 30% of oligotrich numbers” in the ocean and are a “generally minor component of oligotrich communities” (Dolan and Pérez, 2000). However, recent research by Leles et al. shows that mixotrophs represent “approximately 40% of total ciliate biomass” and even influence the biological carbon pump (Leles et al., 2017). In addition, Gast et al. found that mixotrophs “can have significant impact on polar food webs” (Gast et al., 2014). These contradicting statements regarding the importance of mixotrophs in the oceanic food web show the need for further research on exactly what and how they contribute to the ecosystems they populate. Nevertheless, most scientists agree that mixotrophs do impact the oceanic biomes in some

This study has shown that there are significant differences in the catch number between Bassetts Mead and Hale Farm indicating that there could be a larger population of P. leniusculus at Bassetts Mead. However, it was observed on several occasions that over 100 individuals had been removed from the river at Hale Farm in a night. With this evidence, further investigation using multiple mark recapture (MMR) techniques would be required to categorically state whether there is a higher population at one of the locations. Furthermore, this could indicate that the ARTs do not provide a representative sample of the resident population. However, P. leniusculus resides in crevices and burrows during daylight hours and the ARTs are designed to

In the Euarthropoda nervous system, there are three anterior neuromeres, namely, protocerebrum, duetocerebrum and tritocerebrum. The esophagus of Euarthropoda passes through deutocerebral segment,

On average, the Lymnaea stagnalis, commonly known as the great pond snail, is less than five centimeters in length (Kemenes & Benjamin, 2009). Taxonomically, it is a member of the kingdom Animalia and the phylum Mollusca (Budha, P.B., Dutta, J., & Daniel, B.A, 2010). As a part of this phylum, the Lymnaea stagnalis possesses typical molluscan traits, such as a bilateral body and a foot on its underside (Dillon, 2000). In addition, great pond snails have two sensory antennae used for "vision" (Thorp & Covich , 2001). Taxonomists classify this organism into the class Gastropoda and order Hygrophila, because of its hard shell and lack of an operculum, a flap that covers the shell opening (Budha et al., 2010 ; Dillon, 2000). The great pond snail is part of the Lymnaeidae family under the genus Lymnaea and the species Stagnalis (Budha