ABIN VARGHEESE: 2015

Theodor Schwann

Theodor Schwann (7 December 1810 – 11 January 1882) was a German physiologist. His many contributions to biology include the development of cell theory, the discovery of Schwann cells in the peripheral nervous system, the discovery and study of pepsin, the discovery of the organic nature of yeast, and the invention of the term metabolism. Schwann was born in Neuss. His father was a goldsmith, later a printer. Schwann studied at the Jesuits College in Cologne, and then at Bonn, where he met physiologist Johannes Peter Müller.

Contributions

It was during the four years spent under the influence of Müller at Berlin that Schwann's most valuable work was done. Müller was at this time preparing his great book on physiology, and Schwann assisted him in the experimental work required. Schwann observed animal cells under the microscope, noting their different properties. Schwann found particular interest in the nervous and muscular tissues. He discovered the cells which envelope the nerve fibers, now called Schwann cells in his honor.

Schwann discovered the striated muscle in the upper esophagus and initiated research into muscle contraction, since expanded upon greatly by Emil du Bois-Reymond and others. Müller directed Schwann's attention to the process of digestion, and in 1837 Schwann isolated an enzyme essential to digestion, which he called pepsin.

Schwann became chair of anatomy at the Belgian Catholic University of Leuven in 1839. Here he produced little new scientific work, the exception being a paper establishing the importance of bile in digestion. He nonetheless proved to be a dedicated and conscientious professor.

In 1848, his compatriot Antoine Frédéric Spring convinced him to transfer to the University of Liège, also in Belgium. At Liège, he continued to follow the latest advances in anatomy and physiology without himself contributing. He became something of an inventor, working on numerous projects including a human respirator for environments where the surroundings are not breathable.

In his later years, Schwann found growing interest in theological issues. Three years after retiring, Schwann died in Cologne on 11 January 1882.

Cell Theory

In 1837, Matthias Jakob Schleiden viewed and stated that new plant cells formed from the nuclei of old plant cells. While dining that year with Schwann, the conversation turned on the nuclei of plant and animal cells. Schwann remembered seeing similar structures in the cells of the notochord (as had been shown by Müller) and instantly realized the importance of connecting the two phenomena. The resemblance was confirmed without delay by both observers, and the results soon appeared in Schwann's famous Microscopic Investigations on the Accordance in the Structure and Growth of Plants and Animals, in which he declared that "All living things are composed of cells and cell products". This became cell theory or cell doctrine.

In the course of his verification of cell theory, Schwann proved the cellular origin and development of the most highly differentiated tissues including nails, feathers, and tooth enamel. Schwann established a basic principle of embryology by observing that the ovum is a single cell that eventually develops into a complete organism.

In 1857, pathologist Rudolf Virchow posed the maxim Omnis cellula e cellula—that every cell arises from another cell. By the 1860s, cell doctrine became the conventional view of the elementary anatomical composition of plants and animals. Schwann's theory and observations became the foundation of modern histology.

MODERN INSTRUCTIONAL APPROACHES AND TECHNIQUES

Submitted To Submitted By

Smt.Kalyani Rajendhran Abin Vargheese

Lecturer in Natural Science Natural Science

Sabarigiri College of Education Reg No:18114379001

Anchal Sabarigiri College of Education

Anchal

INTRODUCTION

Teachers aspire to have all of their students learn. This aspiration of reaching all students spans disciplines, age levels and all varieties of institutions. Most teachers do so out of a genuine love for their discipline and a desire to share the wonder of their chosen field with others.

The modern instructional approaches and techniques like

v Jigsaw technique

v Circle learning

v Concept Mapping

v Think -Pare Share

The co-operative learning and collaborative learning re related with modern instructional approaches or techniques.

Collaborative learning is a situation in which two or more people learn or attempt to learn something together co-operative learning is one of the most remarkable and fertile areas of theory, research and practice in education. It is an instructional method that encourages students to work in groups to master material presented by the teacher co-operative learning utilizes ideas of vygotsky, piaget and kohlberg in that both the individual and the social setting are involved in the learning process as students attempt to initiate life learning. There are two cognitive theories that are directly applied to co-operative learning, the developmental participation in the process of education.

THINK-PARE-SHARE

Think – pare-share is the method of co-operative learning. It allows students to engage in individual and small group thinking before they are asked to answer questions in front of the whole class. There are four steps in this method. In the fist step, groups of our students listen to a question posed by the teachers. Secondly, individual students re given time to think and then write their responses. Thirdly pairs of students read and discuss their responses. Finally, a few students are called on by the teacher to share their thoughts and ideas with the whole class. This method can be very useful and work well in the science classroom due to the continual request of science teachers having students formulate hypothesis about the out come of an experiment before it is done.

JIGSAW TECHNIQUE

The jigsaw technique is a method of co-operative learning. The key to implementation of jigsaw is the creation of gap in students information and using this gap as a motivator for their further involvement in the learning processes. Two types of Jigsaw technique are occurred.

Jigsaw I

Jigsaw II

Jigsaw I has main components: reading, expert group discussion, team report, testing and team recognition. In Jigsaw after the material to be learnt is divided in two separate units,

v It is presented in ‘base groups’ or ‘home teams’ of 4 or 6 heterogeneous members assembled by the teacher.

v Individual members of the base groups are then given separate parts of the whole academic textual material.

v Each home team takes responsibilities for one aspect of the problem in question.

v Having learned parts for learning, they some together in expert or study groups to study discuses and refine their understanding of their share parts.

v Then everyone has digested the materials, they return to their base groups turns to teach what they learned to their teammates.

v Therefore they all fill their gaps of knowledge in mutual communicative environments and in fact complete the jigsaw.

Jigsaw II is different from Jigsaw I in such a way that each student should study the whole assignment rather than a section of it. After the teacher introduces the whole them each member is asked to study a specific segment of the topic thoroughly.

§ Individuals meet their other team members who have the same topic in ‘expert teams’,. They at this stage in their home teams, also lean something more.

§ In the areas they have not been provided with resources or sufficient knowledge from others in expert teams.

§ Finally they re subjected to a class wide discussion or a question and answer session.

§ They also take a test which covers the entire sub topic.

§ Jigsaw II stresses on individuals improvement evaluation.

CIRCLE LEARNING

The use of a circle as both the organizational structure and descriptive metaphor for a meeting of equals is likely to have been a part of our history for as long as fire has. The learning circle is a mechanism for organizing and honoring the collective wisdom of the group and is present in many indigenous cultures.

The overtime and across countries, civic organizations, neigh our hood communities, trade unions, churches and social justice groups have used the idea of learning circles. Many educators are using learning circles to connected students from around the world. Researchers have used learning circles as a form of professional development to improve their practice.

MODELS OF LEARNING CIRCLES

Learning circles have been used for centuries with students and adults in many different contexts. Two models are described here but others may exist.

Model 1: Open Agile Learning Circle.

Open agile is an agile system of project and team management.

· In the open Agile system, the learning circle is a simple and practical model of selective Learning”

· The learning circle is one of open Agiles three foundations, alongside Truth fullness and consultative Decision – Making.

This model describes learning as a series of four steps. They are:-

Reflection

Learning

Planning

Action

Reflection:-

The reflection step is a pause in our activities where we gather data, impressions, history, stories, and any other observations about what we have done.

Learning:-

In the learning step we carefully examine the observations made in the reflection step and “discover” new insights, skills, relationships, structures, failures or any other conceptual changes.

Planning

In the planning step we apply the conceptual understandings we have developed. We use these newly discovered principles to systematically to create a plan of action. We should directly reflected in our planning each insight or principles we have learned.

Action

In the action step, as an individual, team, or organization we carry out the plans we have created. We do our work. In order to do this affectively we must have courage to plunge into the unknown.

Four capacities of open Agile Learning Circle

Detachment

The capacity for detachment supports the reflection step. Detachment is openness.

Search

The capacity for search supports the learning step.

Love of the work

The capacity for love of the learning supports the planning step. Love creates openness to guidance.

Courage

The capacity for courage supports the action step. Courage encompasses conscious choice, volition, and willingness.

Model 2: Distributed Leadership and Collaboration in Online learning circles.

In this, model, learning circles are described as a structure or distributed leadership in collaborative learning contexts. A learning circle is a highly interactive, participatory structure for organizing group work. This model is described by a

Ø Set of defining dimensions.

Ø Norms that support the interaction.

Ø The phase structure that guides the process.

CONCEPT MAPPING

v A concept Map is a diagram that depicts suggested relationships between concepts.

v It is a graphic tool that designers, engineers, technical workers and others use to organize and structure knowledge.

v A concept map is typically represents ideas and information as boxes or circles, which connects with labeled arrows in a downward-branching hierarchical structure.

v The technique for visualizing the relationships among different concept is called concept mapping.

v A concept map is a way of representing relationships between ideas, images or words in the same way that a diagram represents the grammar of a sentence, a road map represents the locations of highways and towns and a circuit diagram represents the working of an electrical appliance.

History of Concept Mapping

§ The technique was first developed by Joseph D Novak and his research team at Cornell University in 1970.

§ It has been used as a tool to increase meaningful learning in the sciences and other subjects.

§ Concept maps have its origin in the learning movement called constructivism.

§ Novak’s work is based on the cognitive theories of David Ausubel who stressed the importance of prior knowledge in being able to lean new concepts.

§ Novak state that meaningful learning involves the assimilation of new concepts and propositions into existing cognitive structure.

§ Ray Mc Aleese in a series of article, has suggested that mapping is a process off-loading.

§ Mc Aleese suggests that the powers of making knowledge explicit using nodes and relationship allows the individual to become aware of what they know and a result to modify what they know.

Uses of concept mapping

v Concept maps are used to stimulate generation of ideas and are believed to aid creativity.

v It is also used for brain storming

v Used to communicate complex ideas.

v Note taking and summarizing gleaning key concepts their relationships and hierarchy from documents and source material.

v New knowledge creation.

v Instructional knowledge preservation.

v Collaborative knowledge modeling and the transfer of expert knowledge.

v Enhancing meta cognition.

v Improving language ability.

v Knowledge elicitation.

REFERENCE

Mathew Mariamma; Teaching science for Biological & Physical Science , NAS publishers, Malappuram, 2014 p.p.167-173.

Aggarwal.J.C (2001) Principles Methods and techniques of teaching. Vikas publishing house, Mumbai PP 400-403.

ABIN VARGHEESE

Thursday, November 12, 2015

രക്തം (POWER-POINT)

DOUBLE CIRCULATION IN HUMAN HEART (VIDEO)

Theodor Schwann

Important Days related to Science:

Important Days related to Science:

Thursday, October 8, 2015

Pisci culture

Mushroom culture

Horticulture

Floricultute

Cuni culture

Apiculture

Powerpoint

Online Assignment