...different magnitudes of action potentials. Compound action potentials are also graded, meaning the greater the stimulus, the greater the action potential. 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? The frog sciatic nerve gives a graded response de to the nerve being a bundle of axons and not a single axon, resulting in it not showing the “all or none” rule of an axon. In this experiment, if one axon is generating an action potential, then a small nerve impulse will be seen. If all axons are simultaneously generating action potentials, then a large nerve impulse will be seen. This means that the sciatic nerve impulse is graded due to it being able to be none, small, medium, large, or maximal. 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? To produce a maximum response, the whole nerve must be stimulated. If the stimulus voltage is increased slowly, you may observe discrete jumps in...
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...this property since they are a bundle of neurons and have different magnitudes of AP's. Thus compound action potentials are graded. That is, the greater the stimulus, the greater the action potential. 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? The frog sciatic nerve gives a graded response because the nerve is a bundle of axons (CAP) and not a single axon (thus it does not show the all or none response of an axon-either generating an action potential or not). If one axon is generating an action potential then a small nerve impulse is witnessed, if all axons are simultaneously generating action potentials then a large nerve impulse is witnessed. Thus the nerve impulse is graded (it can be none, small, medium, large, larger, maximal). 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? A minimum of 140 mV is required to produce the maximum Cap. 100% of the excitable nerve fibers were excited to produce the maximal response. We know this because all of the A-alpha fibres making up the nerve have been excited and are conducting action potentials. Even if you were to increase the voltage past 140 mV, the AP would not continue to increase in amplitude. 4. In this exercise, you examined the effect of...
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...Bizarre extinct frog brought back to life March 16, 2013, 10:55 am By environment reporter Sarah Clarke ABC Imagine a frog that can swallow its eggs, brood its young in its stomach and give birth through its mouth. The gastric brooding frog existed 30 years ago, but the extraordinary amphibian is now extinct. In a world first, a team of Australian scientists has taken the first major step in bringing it back to life. They have successfully reactivated its DNA and produced an embryo. Professor Mike Archer from the University of New South Wales is part of the team, which also includes researchers from the University of Newcastle. He says the amphibian was no ordinary frog. "In the stomach these eggs went on to develop into tadpoles and the tadpoles then went on to develop into little frogs," he told ABC radio's AM program. "And like any pregnant mum, when you have little babies rattling away in your stomach saying, 'let me out', she would then open her mouth and out would pop little frogs. "The first people that saw that were aghast. By the time anybody got excited about it, suddenly it was extinct. "So that's certainly one of the driving reasons why this would be a focal animal for seeing if we can de-extinct this amazing frog." That is exactly what a team of Australian scientists is doing. After locating a few carcases stored in a deep freezer, they have been able to recover tissue from the gastric brooding frog. Using a laboratory technique known as somatic cell nuclear transfer...
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...Frogs vs. Toads Frogs and toads are “small, tailless animal” that belongs to the amphibian class. (Forester 536 & Gibbons 303) Everyone thinks that frogs and toads are different from one another but in fact “there is no clear distinction between” them (Burnie & Wilson 440). Most people find it very difficult to differentiate between a frog and a toad that they often mix them up. Their physical features are very much alike but they are different on the basis of anatomy and habitat. When you see a creature hopping along the side of the creek, can you tell if it’s a frog or a toad? Frogs are very unique because “some frogs have colorful markings” (Forester 536). While as toads are marked in a “drab shades of brown, tan, gray, or black that serves as camouflage” (Campbell 217). Besides their markings, “almost all frogs have the same basic body structure” (Forester 536). Frogs have “long, powerful hind legs, which they use for jumping” (Forester 536). “Frogs can leap long distances, but also use their limbs to swim, burrow, and even to glide from tree to tree” (Wake 337). Unlike frogs, toads “generally have squat bodies and short legs” (Campbell 217). They do not “jump” like frogs so they “make short hops or even walk” (Campbell 217). As opposed to skin, frogs have “thin, moist skin” (Forester 536) and “the skin of most toads is dry, rough, and covered with warts” (Gibbons 303). There is an advantage to a toad’s dry skin. It’s “warty skin allows it to inhabit drier regions than...
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...oggy1962 first attempt 1.1 The four basic human body structures and their units are cells, tissues, organs and systems. Cells – these are the smallest independent unit in the human body and can only be seen with a microscope. There are many different types, shapes and sizes. Each type is specialised and carries out a particular function in the body. The types of cells include epithelial cells (the skin), muscle cells, nerve cells, bone cells and blood cells. Every cell has a nucleus, (except red blood cells), a cell membrane and cytoplasm. The nucleus contains the body’s genetic material; this directs all the metabolic activities of the cell. The cell membrane is semi-permeable and surrounds the cytoplasm. Its function is to protect the interior of the cell by allowing certain substances in and keeping others out. The cytoplasm is a gel like substance in which organelles are suspended. These include ribosomes, lysosomes, endoplasmic reticulum, golgi apparatus, mitrochondria, and centrioles. The organelles each have different functions within the cell. Tissues – a group of cells is known as a tissue. Different types of tissues are found in different organs. Humans have four different types of tissue: Epithelial tissue – this covers the body surface. The major functions are protection, secretion, absorption and filtration. Connective tissue – this is the most abundant tissue in the body. It binds structures together and forms a framework and support for organs. It...
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...Introduction This essay will consider the structure and function of the 11 systems within the human body. It will detail the interrelationship between the nervous system and the musculoskeletal system and between the circulatory system and the lymphatic system. It will then explain the roles of the circulatory and lymphatic systems in the immune response and the role of hormones in metabolism. Human Body Systems The human body is made up of 11 separate but interconnected systems (Sherwood, 2007). These are the skeletal, muscular, circulatory, respiratory, digestive, excretory, nervous, integumentary, immune, endocrine and reproductive systems. The success and survival of the human body is dependent on the ability of separate body systems to work together. The skeletal system provides structure for the human body, stores minerals, produces blood cells and provides protection for delicate organs (Kelly, 2004). 206 bones are connected with ligaments, muscles and tendons, with cartilage, a softer cushion like material, providing protection in jointed areas. Body movements are controlled by the muscular system, with these muscles being connected to bones via tendons (Adams, 2004). Stimulation of these muscles by the nervous system causes contraction and the resulting movement of bones to which they are attached. A number of involuntary muscles ensure the respiratory and circulatory systems continue with contraction of the heart and lungs (Adams, 2004). The heart is central...
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...Cell Theory Cell Theory is a way to describe the biology of living things. Cell theory says that the cell is the basic unit of life. Cells by themselves are alive, but they can also be part of a larger living thing. The smallest living organisms (like bacteria but not viruses) and the biggest ones (like humans and whales) are all made of cells. Very small organisms like bacteria and amoebas are only made of one cell each, so they are called unicellular organisms ("uni" means "one"). Larger organisms are made of many cells, and they are called multicellular organisms. Definition: The Cell Theory is one of the basic principles of Biology. Credit for the formulation of this theory is given to German scientists Theodor Schwann, Matthias Schleiden, and Rudolph Virchow. The Cell Theory states: * All living organisms are composed of cells. They may be unicellular or multicellular. * The cell is the basic unit of life. * Cells arise from pre-existing cells. The modern version of the Cell Theory includes the ideas that: * Energy flow occurs within cells. * Heredity information (DNA) is passed on from cell to cell. * All cells have the same basic chemical composition. Animal Tissues 1. Epithelial: In Greek, ἐπί (epi) means "on" or "upon", and θηλή (thēlē) means "nipple". Epithelial layers are avascular, so they must receive nourishment via diffusion of substances from the underlying connective tissue, through the basement membrane. Epithelia...
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...tissue largely caused by a virus that enters the CNS when the person experiences a viral disease such as measles or mumps or through the bite of a mosquito or tick. 2. Hydrocephalus—An abnormal increase of cerebrospinal fluid in the brain that causes the ventricles of the brain to dialate, resulting in an increased head circumference in the infant with open fontanel(s); a congenital disorder. 3. Neuralgia—Severe, sharp spasmlike pain tht extends along the course of one or more nerves. 4. Narcolepsy—Uncontrolled, sudden attacks of sleep. 5. Dysphagia—difficult speech. 2. Pathologial Conditions 1. Anencephaly—An absence of the brain and spinal cord at birth, a congenital disorder. 2. Bell’s palsy—A temporary or permanent unilateral weakness or paralysis of the muscles in the face following trauma to the face, and unknown infection, or a tumor pressing on the facial nerve rendering it paralyzed. 3. Carpal tunnel syndrome—A pinching or compression of the median nerve within the carpal tunnel due to inflammation and swelling of the tendons, causing intermittent or continuous pain that is greatest at night. 4. Cerebral concussion—A brief interruption of brain function, usually with a loss of consciousness lasting for a few hours. 5. Cerebral contusion--a small, scattered venous hemorrhage in the brain (or better described as a “bruise” of the brain tissue) occurring when the brain strikes the inner skull. 6. Cerebrovascular accident (CVA)—involves...
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...made an unusual discovery of a new species of frogs. The strange looking new amphibian is known to be a sole surviving member of amphibians that evolved more than 130 million years ago. Scientist calls this species discovery as a ‘once in a century find’ because of it’s belonging to an ancient group of amphibians that once shared the same land with dinosaurs. Formally discovered in 2003, the poignous frog, also known as the “Purple Frog”, has been the talk of all scientist discoveries because of its comic features and behaviors. Although this new species has recently been discovered with highly distinctive and comical appearances, its behaviors adaptive values benefit the amphibian by increasing its total fitness. However scientists might now be able to research this rare species because it is slowly decreasing in population. The purple frog has a sidesplitting appearance with a distinctive habitat in an unusual range of geographical location. This new species of frog can be described as a typical frog at first glance but as you pay closer attention you notice its distinctive appearances compared to other species of frogs. The body has a similar shape like most frogs yet it has a plump bloated body shape with short fore and hind limbs that end in webbed feet with rounded toes. Each hind foot has a large, white wart look-a-like growth that is most likely used for digging in their moist soil locations. The small head shape of the frog seems almost too small for such a short body...
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...Frogs are a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (Ancient Greek an-, without + oura, tail). The oldest fossil "proto-frog" appeared in the early Triassic of Madagascar, but molecular clock dating suggests their origins may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is found in tropical rainforests. There are approximately 4,800 recorded species, accounting for over 85% of extant amphibian species. They are also one of the five most diverse vertebrate orders. The body plan of an adult frog is generally characterized by a stout body, protruding eyes, cleft tongue, limbs folded underneath and the absence of a tail. Besides living in fresh water and on dry land, the adults of some species are adapted for living underground or in trees. The skin of the frog is glandular, with secretions ranging from distasteful to toxic. Warty species of frog tend to be called toads but the distinction between frogs and toads is based on informal naming conventions concentrating on the warts rather than taxonomy or evolutionary history; some toads are more closely related to frogs than to other toads. Frogs' skins vary in colour from well-camouflaged dappled brown, grey and green to vivid patterns of bright red or yellow and black to advertise toxicity and warn off predators. Frogs typically...
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...tree. On the ground at its feet, something strangely familiar hops by: a frog. Ichthyostega, prehistoric predecessor to the modern frog, lived 370 million years ago during the Devonian Period. Sometimes referred to as "the first four-legged fish," skeletal remains of this earliest-known amphibian were first discovered in East Greenland. Surprised? Few people realize just how ancient frogs are. For 190 million years, the ancestors of modern frogs have roamed (if not ruled) the earth, looking much the same as they do today. The secret to their success is their amazing adaptability. As amphibians, frogs have one webbed foot in each of two worlds. The advantages of this double life are clear to see: Are land predators giving you trouble? Dive into the water. Not enough to eat in the pond? Hop out and see what they're serving on shore. Frogs have evolved to live in an astounding variety of climates. They can be found just about anywhere there's fresh water, from the desert to the Arctic, on all continents except Antarctica. Though they thrive in warm, moist tropical climates, frogs also live in deserts and high on 15,000 foot mountain slopes. The Australian water-holding frog is a desert dweller that can wait up to seven years for rain. It burrows underground and surrounds itself in a transparent cocoon made of its own shed skin. Frozen Wood Frog Like all amphibians, frogs are cold-blooded, meaning that their body temperatures change with the temperature...
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...Lesson Plan Cindy Dean PED212 Foundation of Movement Motor Activities Instructor: James Woodward January 13, 2014 Lesson Plan For this assignment paper I have chosen elementary school students which are in the third grade. The group of students range from seven to nine year old. Evolving achievements for several third grade students it is likely that they go through physical development at this age group include stable development example. At this age their gross motor skills are more developed than their fine motor skills. Elementary students learn through movement. Physical education is an important part during these developmental years. Children are able to run and jump as well as having control of large muscles in their legs. The body and mind rarely work together. They have a difficult time holding small things, catching or putting something together using their fingers. The total number of students in this lesson plan classroom is thirty. The school is Mary L. Fonseca Elementary. There will be some fundamental skills that we will try to teach the elementary students; for example jumping and landing. Locomotors skills we will teach them skipping, running, sliding, galloping, leaping, hopping, and non- locomotors skills students we will teach twisting. The student objective goals would be that the end of the course students will successfully jump and land on balance in different ways. The students successfully improve their distance as well as height....
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...Jennifer Czachura 3/27/07 Critical Thinking Essay Kim Groninga “I’m Nobody! Who are you?” by Emily Dickinson Most people feel invisible at some point in their lives; whether it’s because they’re in the shadow of an older sibling, because they are shy, or simply because everyone around them has been busy, it doesn’t make much difference. It’s still a horrible thing to feel like no one even realizes you’re alive or that you’ve been doing things. Emily Dickinson felt this way often; she lived at home and didn’t leave the house much, mostly corresponding with people by letters. However, her invisibility didn’t bother her too much, and that is what this poem is all about. When you feel invisible, you aren’t alone, because someone else is feeling invisible too. Dickinson starts out the poem introducing herself, ”I’m Nobody! Who are you?” (1) Being nobody can mean a lot of things; it could mean she’s no one important, no one special, no one significant, or no one that everyone knows. However, she could also be nobody to many people simply because she doesn’t try to stand out or feel important. She is content just being herself, living her plain, simple life and doing things that make her happy. Being nobody makes her somewhat mysterious; she’s obviously a person, but most people don’t know who she really is. This also relates to the second line in the poem, “Are you – Nobody – too?” (2) Dickinson’s question of the reader seems to show tha t being nobody is something everyone feels at...
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...Edwards Frogs vs. Toads Most people find it difficult to differentiate a frog from a toad. They normally mix them up. Although they seem similar in a lot of areas, they certainly have numerous dissimilarities too. Frogs are found in many different shapes, sizes, and colors. Frogs have smooth, wet skin. They live most of the time in or near water. They have different eye colors including brown, silver, green, and even red along with different shapes and sizes. Some of the frogs have sticky feet while some are webbed. It is obvious that not even all frogs have same qualities. Toads too have numerous shapes, sizes, and textures, but they don’t have much variety in color. Toads are fat and have rough skin. They do spend most of their time in water, but they live in moist places like woods, fields, and even gardens. Their pupils do have different shapes, sizes, and colors, but generally they are egg-shaped, small and black. They also have webbed feet. Toads and frogs have the same way to catch and eat food. Both of them use their tongue to catch prey. But a frog has a very small tooth around its upper jaw edge to capture food, but a toad doesn’t have any teeth at all. Toads eat almost the same foods as frogs like bugs, insects, fish, etc. In Conclusion, frogs and toads do seem similar but they have several qualities regarding shape, size, color, and texture that make them different. So it should be crystal clear that people can mistake the difference between a frog and a...
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...Myths The Fox with the Nine-Tails The Fox with the Nine-Tails – Korea In the spirit of Halloween, I asked a teacher if Korea had any scary stories. “Kumiho, the Fox with the Nine-Tails”, he said. Of course my interest was peaked and so he said, “Kumiho is a nine-tailed fox who eats the hearts of humans in order to survive. She digs up graves sometimes to find hearts or attacks men.” He couldn’t tell me much more so I dug up some info. Unfortunately it all seems like the information is taken from a commentary on a book that holds the oral stories of Korea, Compendium of Korean Oral Literature. This is more or less taken from Wiki and all other sources that say the same basic information: A fox that lives a thousand years turns into a Kumiho, like its Japanese and Chinese counterparts (the kitsune and the huli jing). The current Japanese kitsune can sometimes be evil and sometimes good, but the Korean counterpart over the years has become a symbol of evil. Legends tell that while the Kumiho is capable transforming its appearance, there is still something persistently fox-like about it. In Transformation of the Kimono, a Kumiho transforms into an identical likeness of a bride at a wedding. Not even the bride’s mother can tell the difference. The Kumiho is only discovered when her clothes are removed. As the mythology of the Kumiho evolved it was later believed that a Kumiho had to consume human hearts in order to survive. Another version of the mythology, however...
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