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Video

Siemens Stiftung

Unterrichtsfilme: Der Treibhauseffekt

Video (01:24 Minuten): Das Prinzip des Treibhauseffekts wird erklärt und seine Bedeutung für das Ökosystem Erde wird herausgestellt. Der Film beginnt mit einer kurzen Einführung zum Treibhausgas Kohlendioxid. Anschließend wird das Funktionsprinzip des Treibhauseffekts grafisch dargestellt. Dabei wird zum einen deutlich, dass ohne den natürlichen Treibhauseffekt kein Leben auf der Erde möglich ist, zum anderen, dass der anthropogen verursachte Treibhauseffekt eine schädigende Wirkung auf das Erdklima hat. Als Ursache dafür wird das vom Menschen produzierte Kohlendioxid genannt. Der Film endet mit der weiterführenden Frage "... und woher kommt dieses zusätzliche CO2?". Hinweise und Ideen: An diese Filmsequenz kann z. B. eine detaillierte Behandlung der schädlichen Klimagase angeschlossen werden. Das Video ist ein Ausschnitt aus der didaktischen DVD "Das grüne Paradoxon - Warum die Erde wärmer wird".

Video

Siemens Stiftung

Solar cell

Video (00:30 minutes): Shows how a solar cell works based on a simple experiment and explains the theory. The video presents the solar cell as a supplier of power. When illuminated by a lamp, a wind turbine begins to turn. With the aid of a graphic, the flow of current is explained on the basis of the band model of solids and the quantum nature of light. This video is an excerpt from the teaching DVD, "Optik - Eigenschaften des Lichts".

Video

Siemens Stiftung

¿Cobreado espontáneo? (con subtítulos)

Video (02:33 minutos, sin sonido):
El experimento muestra cómo la superficie de una moneda de 1 euro depositada sobre papel de aluminio en una solución de sulfato de cobre se recubre con el cobre que se precipita de la solución.


Todos los metales menos nobles que se sumergen en una solución salina de un metal más noble entran en un proceso de disolución y dan lugar a la precipitación del metal más noble. Si se deposita una moneda de aleaciones relativamente nobles (latón, níquel) sobre papel de aluminio (un metal extremadamente común), la superficie de la moneda se recubre de cobre (Cu). El objeto que se desea recubrir puede estar hecho de cualquier material conductivo químicamente inerte, también de grafito, p. ej. Los electrones para la precipitación del cobre proceden del aluminio (Al) diluido. El proceso es, por así decir, un "cortocircuito interno? de un elemento de Cu y Al. El cobre precipitado tiene al principio un color rojizo y más adelante se oxida en óxidos de cobre oscuros bajo la influencia del oxígeno del aire.

Algunas escenas ofrecen explicaciones en forma de subtítulos. La película está también disponible sin subtítulos en el Portal de medios didácticos: "¿Cobreado espontáneo? (sin subtítulos)?.

Indicaciones e ideas:
Las Instrucciones sobre experimentación "A3 Pila de limón y otras pilas? contiene dos experimentos parciales (4 y 5) que trabajan con sulfato de cobre. No obstante, por razones de seguridad, algunos profesores prefieren no llevar a cabo experimentos con sulfato de cobre en el aula de clase. El profesor puede proyectar en ese caso este video con el experimento parcial 5 de manera alternativa. De esa forma es posible comprender sistemáticamente el experimento en su conjunto, que consta de experimentos parciales estructurados en muchos pasos didácticos.
En el experimento parcial 5 del medio "A3 Pila de limón y otras pilas (Instrucciones para los alumnos)?, que se encuentra en el portal de medios didácticos, hay instrucciones de experimentación detalladas.

Video

Siemens Stiftung

Amylase (en)

Video (00:51 minutes):
The breakdown of polysaccharides into glucose by amylase and maltase.

The animation illustrates how the enzyme amylase breaks down polysaccharide chains into maltose and how the enzyme maltase further breaks down the maltose into two glucose molecules.

The video is an excerpt from the teaching DVD "Basiswissen BIO III - Enzyme und Tierzellen" (English audio channel available).

Medientypen

Video

Lernalter

11-18

Schlüsselwörter

Carbohydrate Enzyme Metabolism

Sprachen

Englisch

Video

Siemens Stiftung

Amylase (de)

Video (00:51 Minuten):
Aufspaltung von Mehrfachzucker in Glukose durch Amylase und Maltase.

Die Animation veranschaulicht die Aufspaltung von Mehrfachzuckerketten in Maltose durch das Enzym Amylase sowie die weitere Spaltung der Maltose in zwei Glukosemoleküle durch das Enzym Maltase.

Das Video ist ein Ausschnitt aus der didaktischen DVD "Basiswissen BIO III - Enzyme und Tierzellen".

Medientypen

Video

Lernalter

11-18

Schlüsselwörter

Enzym Kohlenhydrate Stoffwechsel

Sprachen

Deutsch

Video

Siemens Stiftung

Meat and Sustainability

Video:
Animated film that clearly shows the impact of high meat consumption in Germany

On average, each German eats nearly 90 kilograms of meat per year. That is excessive and problematic in many ways. Industrial production of meat is unsustainable in many aspects - area of land use, global food supply, climate change, animal rights, pollution, and health.

What problems are specifically caused by industrial meat production? What are the global consequences? What can be done about it?

Video

Siemens Stiftung

Verification of amino acids and proteins in the human body (with subtitles)

Video (01:33 minutes, without sound):
The experiment shows how ninhydrin solution can be used to verify the presence of amino acids in human sweat.

A student makes a handprint on a piece of filter paper. The teacher then sprays the paper with ninhydrin solution. After a certain time and with the addition of heat, the handprint appears with a bluish-purple coloring. The heat is added to accelerate the development process. (However, the experiment works only with a very sweaty hand.)

For some scenes, explanations are displayed as subtitles. However, the film is also available without subtitles on the media portal: "Verification of amino acids and proteins in the human body (without subtitles)."

Information and ideas:
The experiment "Verification of amino acids and proteins in the human body" involves ninhydrin solution. For safety reasons, however, some teachers may not want to allow any experiments involving ninhydrin solution in their classrooms. In this case, the teachers can show the video as an alternative.
Detailed experimentation instructions are found in the medium "Verification of amino acids and proteins in the human body (student instructions)," which is available on the media portal.

Medientypen

Video

Lernalter

11-18

Schlüsselwörter

Amino acids Metabolism

Sprachen

Englisch

Video

Siemens Stiftung

Boosting battery performance (without subtitles)

Video (04:33 minutes, without sound):
The experiment with the Cu/Zn element shows that a battery reaches its full capacity only when Cu2+ ions are present.


The combination of two metals is often misconstrued as an essential feature of electrochemical elements (batteries, accumulators). In reality, however, an element consists of the combination of two metal redox pairs. The zinc/copper battery often used in the classroom - made with fruit, vegetables, or even with acid or saltwater - is in reality a zinc/hydrogen element (Zn/Zn2+ and H/H+). The voltage and power are therefore less than the values for Zn/Cu. The battery does not become a Zn/Cu element (Zn/Zn2+ and Cu/Cu2+) until the copper half-cell also contains copper ions from the dissolved copper sulfate. Then the element reaches full voltage and power.

The film is also available on the media portal as a version in which explanations are displayed as subtitles for some scenes: "Boosting battery performance (with subtitles)."

Information and ideas:
The experimentation instructions for "A3 Lemon batteries and other batteries" contain two subexperiments (4 and 5) that involve copper sulfate. For safety reasons, however, some teachers may not want to allow any experiments involving copper sulfate in their classrooms. In this case, the teachers can show this video with subexperiment 4 as an alternative. This allows the overall experiment consisting of subexperiments set up as many didactic steps to be completed systematically anyway.
The teacher should point out to the students that the simplified experiment shown in the film works without a separator. Detailed experimentation instructions are found in the medium "A3 Lemon batteries and other batteries (student instructions)" for subexperiment 4, which is available on the media portal. The technical explanation is found in the medium "A3 Lemon batteries and other batteries (teacher instructions)."

Video

Siemens Stiftung

The Ear, Hearing and Hearing Impairment;: Water as wave model

Video (00:07 minutes, without sound):
A stone is thrown into calm water, ripples are formed.

The vibrations emitted by a source of sound can be compared with the ripples or waves created when a stone is thrown into calm water.
It is, however, directly comparable only as far as the concentric shape of propagation is concerned. Looked at in detail, the vibrations are in fact very different.

Information and ideas:
Students can do the experiment themselves on an excursion out of school.

Relevant for teaching:
Acoustic phenomena
Sound/acoustics: parameters
Communication and understanding
Vibrations and waves

Video

Siemens Stiftung

Subtraktive Farbmischung

Video (00:12 Minuten, ohne Ton):Ein Schüler erzeugt durch Übereinanderlegen von Farbfolien in Blaugrün, Gelb und Purpur Mischfarben und Schwarz.Grundfarben sind Gelb, Cyan und Magenta. Werden alle drei Farben in voller Intensität zu gleichen Anteilen zusammengemischt, erhält man Schwarz, d. h. es wird kein Licht reflektiert.Hinweise und Ideen:Subtraktive Farbmischung wendet man beim Arbeiten mit Farbsubstanzen an und ist daher jedem aus dem Kunstunterricht bekannt, beispielsweise beim Malen mit Wasserfarben. Das gezeigte Beispiel ist leicht durch Schüler nach zu machen. Eventuell statt teurer Foto-Filterfolien billige farbige Klarsichthüllen verwenden!