In the northern leopard frog, there has been experiments conducted regarding eye retraction when swallowing. It has long been held as an assumption that eye retraction may help the frog in pushing the food through the digestive tract. From observing northern leopard frogs from eating 1.5cm long crickets, it shows a high amount of variability as both the eyes and muscular area of the throat are seemed to have make physical contact with the food item. (e.g. Dickerson, 1906 Regal and Gans, 1976 Nishikawa, 2000 Schwenk). In order to conduct this experiment, male northern leopard frogs that have a snout length of 5.5cm to 7.0cm were acquired through commercial purposes. (Scherber, 1782). They were housed according to specific temperature specifications …show more content…
For this experiment, Rana temporaria were utilized since they have two midbrain nuclei that receive impulses since the neurons respond to stimulation of optokinetic pathways. (Cochran). Each of these neurons plays a different role in response types. Examples of such movements in neurons include both upward and downward moving targets from optokinetic perspective. Cells in a specific region have this sensitivity, and can even utilize their stimulation for increasing and decreasing rest rate. Oculomotor neurons were studied because they possess an exclusive upward or downward motion which would make the controls easier to identify and carry out the experiment. (Precht, 1982). Temporal nasal pattern movements are an additional type of neuron that have similar velocity preferences as simple sensory nuclei. To investigate the connectivity between motor and sensory nuclei, the region that they were derived from within the frog was restricted to the pretectum and abducens. A single connection between these areas is suggested through onset latency in antidromically motor neurons, activation of the pretectal cells, horseradish injections which involve labeling the axons, and horseradish injections into the region of abducens which create labeling of cells in pretectal region. (Gaupp, 1896). In this experiment, a length of time of two years and …show more content…
The mouse eyes were significant in that they provided results that can be compared with the data obtained from the frogs. These frog and mouse eyes were studied using X-ray diffraction. The changes regarding light induced reflections were recorded at 0.1seconds and 1.0 seconds in frog and mouse cells. (Chabre and Cavaggioni, 1973). The diffraction of disk membranes was measured to the 10th order to maintain specificity and detailed differences between mammalian and amphibian rod outer segments. For the experiment, a bullfrog ( Rana catesbeiana) eye was used and the frogs were in an environment that provided 12 hours of light and 12 hours of dark at a constant temperature of 8 degrees celsius for one to four weeks. A frog from the group was killed and the head was cut along the middle so that both eyes could be further studied. For the mouse eyes, BALB/C mice also maintained under the same conditions as the frogs were used. However, the eyes from the mice were removed from the sockets by cutting the optical nerve and tissues whereas the eyes on the frog remained intact. A similar X-ray analysis was used for both specimen and involved a beam passing from the back of the eye to the side where the light illuminates the eye from the front. (Corless 1972). A
What is the most important element of a good story? Although interesting characters, engaging plot development and didactic story lines certainly embellish the story, one could argue that the setting is the most crucial. Not only does the setting provide a baseline of necessary background information, it can also be used to enhance the story, just like the other elements listed. Edgar Allan Poe certainly takes advantage of this in “Hop Frog”, “The Cask of Amontillado”, and the “Masque of the Red Death”. In each of these stories, gruesome horrors occur, and because of the ingenious way Poe uses and manipulates the setting to his advantage, these stories’ horrors are amplified. In “Hop Frog” and “The Cask of Amontillado”, the main characters
Thyroid and metabolism hormones play a large role in the daily lives of all living species. Thyroid hormones regulate the metabolism and the metabolism is responsible for maintaining a specific range for the biochemical reactions that occur in the body (Martini 2014). The most important hormone for metabolic maintenance is thyroxine (T4). This hormone also plays a large role in body heat regulation. It is produced by the pituitary gland and secreted by the thyroid gland. The thyroid releasing hormone (TRH) must trigger the thyroid stimulating hormones (TSH) to release thyroid hormones to the thyroid gland. These hormones are under control of the hypothalamus, or main neural control center. Propylthiouracil (PTU) is a medication used to treat
The frog’s back is usually textured with coarse tubercles. Its fingers are thinly webbed while the hind foot is more developed. Large disks exist on the fingers and toes to assist with climbing and sticking to objects (Dickerson, 1969). The male and female Grey Tree Frogs are very similar. They are distinguished by the male having a dark underside of his throat. Also the females ears are smaller then the males (Dickerson, 1969).
Michael DuBois Mrs. Ermis English 1302.NO2 10 April, 2016 Revenge at its Finest Like most of Edgar Allan Poe’s work the concept behind both of these stories is the themes of death and revenge. In both “The Cask of Amontillado” and “Hop Frog”, Poe makes it a point to reveal the struggles of both characters and that they seek revenge for what has happened in their past. In “Hop Frog” he decides he has had enough when the king slaps his friend Trippetta for sticking up for him. Along with all the vicious jokes and torture that he puts on both Hop Frog and Trippetta, the physical abuse was just the thing that puts Hop Frog over his limit. In the short story “The Cask of Amontillado”, Montresor seeks revenge on Fortunato for the rude embarrassing
Jones, D. H. (2006-2010). Chapter 3: The Nervous System and the Brain. Retrieved from http://www.nasalspecific.com/nasalspecific_011.htm
Firstly, there is various of sensing activities as in seeing and hearing as in a sense of understanding of what is seen and heard. Secondly the sense of feeling in numerous parts of the body from the head to the toes. The ability to recall past events, the sophisticated emotions and the thinking process. The cerebellum acts as a physiological microcomputer which intercepts various sensory and motor nerves to smooth out what would otherwise be jerky muscle motions. The medulla controls the elementary functions responsible for life, such as breathing, cardiac rate and kidney functions. The medulla contains numerous of timing mechanisms as well as other interconnections that control swallowing and salivations.
An inspection of the modern animal phyla will reveal that eyes are just as diverse as they are complex. Some organisms like the rag worm have pigmented cup eyes while other like he box jellyfish have two lens eyes and two pairs of pigment pit eyes. To account for the diversity in eye structure, we must first examine the eye ‘prototype’, the original structure that was acted upon by evolution. The simplest organ that can be considered an eye is composed of a single photoreceptor cell and a single pigment cell, without any lens or other refractive body (Arendt, 2003). Such organs are know as eyespots, and...
The red-eyed tree frog has a small body and bilateral symmetry. The body is green with red eyes, webbed orange feet, and blue and yellow legs. The frogs typically weigh between six and fifteen grams. They range in size from 51 to 76 millimeters in length.
Cane toads, an amphibian species that was introduced from Central and South America to Australia in 1935, was expected to protect farmers’ crop and by eating harmful insects. However, not only did they multiply rapidly, but they also threaten small native animals that are not pests. The writer believe building national fence, asking for volunteers, and producing a specific virus can control the population. Unfortunately, the lecturer does not agree with the paper and believe the result may be even more devastating.
The four main components of the eye that are responsible for producing an image are the cornea, lens, ciliary muscles and retina. Incoming light rays first encounter the cornea. The bulging shape of the cornea causes it to refract light similar to a convex lens. Because of the great difference in optical density between the air and the corneal material and because of the shape of the cornea, most of the refraction to incoming light rays takes place here. Light rays then pass through the pupil, and then onto the lens. A small amount of additional refraction takes place here as the light rays are "fine tuned" so that they focus on the retina.
The adaptations that the Axolotl’s have strongly increase their chances of survival and their overall fitness. The Axolotl’s cone shaped teeth allows them to catch food so that they may easily do their “vacuum” action to eat food. This favorable trait grips whatever food they are going to eat, so th...
These tasks are accomplished through the mechnoreceptors of the three semicircular canals, the utricle and the saccule (3). Like the neighboring auditory system, each canal has hair cells that detect minute changes in fluid displacement, but unlike the auditory system, the utricle and the saccule send information to the brain regarding linear acceleration and head tilt. Shaking your head ënoí employs one of these canals. Likewise, there is a canal that detects head movement in the ëyesí position, and there is yet another semicircular canal that detects motion from moving your head from shoulder to shoulder (4).
and the iris which is the colored part of the eye, it regulates the amount of light
Frogs are amphibians in the order Anura. The order Anura is broken down into 22 different families of frogs and toads. Although they belong to the same order, frogs and toads are different in a lot of ways. Some of the more distinct differences are their skin and where they live. Frogs usually have smooth moist skin and toads usually have dry watery looking skin. Frogs spend most of their lives in or near water and toads spend more time on land. Amphibian means "double life." Frogs and toads each have two parts to their lives: when they live on water and when they live land. A frog's life starts in the water when it is hatched from an egg as a tadpole. A tadpole looks very different from an adult frog. A tadpole has a tail, no limbs, and breathes through gills. After a while the tadpole goes through metamorphosis. During the change the frog grows limbs, the tail disappears, it uses lungs to breathe, and it doesn't have to live in water anymore. As a tadpole, the frog feeds mostly on vegetation. The tadpoles have a small rasping mouth suited especially for scraping algea from the bottom of ponds. Depending on the species, it can take a few weeks to a year or more for the tadpoles to become fully grown. Not all frogs hatch as tadpoles. Some species of frogs hatch as froglets. Froglets look just like adult frogs but are a lot smaller. Froglets don't go through a metamophosis. Most species that hatch as froglets are found in dry places. Frogs who live in dry places where rains are seasonal have to grow up quickly because a tadpole will die if their temporary pond dries up. Adult frogs can live in water or on land, but it always needs to be near water so its respiratory organs don't dry out.
This reflected light passes through the lens and falls on to the retina of the eye. Here, the light induces nerve impulses that travel through the optic nerve to the brain, where it makes an image of the object, and then that image is passed on to muscles and glands.The eye is well protected. It lies within a bony socket of the skull. The eyelids guard it in front. They blink an average of once every six seconds. This washes the eye with the salty secretion from the tear, or lachrymal, glands.