LANGUAGE / German and English
DESCRIPTION OF LESSON
KEYWORDS / immune system, immun response, bacteria cell, pathogen, bacteria life style, reproduction (bacteria), multiplying (bacteria), propagation (bacteria), growth (bacteria), exponential growth (bacteria) DNA (bacteria), pili, flagellum
BRIEF OVERVIEW OF LESSON CONTENT / Bacteria are one sort of pathogenes. Students work out the structure/histology of bacteria as well as their life style (life cycle). The goal is to identify the bacterial metabolism as cause of a disease, not the bacterial intention.
SUBJECT COVERAGE / Secondary Science
CURRICULUM / see “Unit of work”
LEARNING OBJECTIVES / Learners …
- explore the typical structure of a bacteria cell (structure knowledge, mental modelling, cognitive load)
- study the exponential growth of bacteria and the dependence of time and temperature (cognitive flexibility). For advanced learners, a link to the mathematical modelling is possible (cognitive flexibility, see also MathFlyer on Shodor.org)
MATERIALS REQUIRED /
- Interactive Whiteboard (alternatively beamer or tablets)
- For less able pupils a real 3D model of a bacteria cell
- Print-out with fotos of various bacteria shapes (or reference of pages in school book
- a chess board and a package of normal rice to reply the Persian fairytale
DURATION / 2 x 45 min
TARGET AUDIENCE / Secondary School (in Germany: Realschule, Gymnasium)
AGE RANGE / 14 – 16
CONNECTION / Lesson 2 of 8 in this Unit of work “Immune System”
ASPECTS FOR COLLABORATION / While exploring the bacteria cell and life style, in-class collaboration throughout all activities of prediction, investigation, recording of results (on IWB) and discussion.
REQUIRED KNOWLEDGE / Basic knowledge about structure of a cell
EDUCATIONAL DESCRIPTION OF LEARNING ACTIVITY / ACTIVITIES
SUGGESTIONS FOR USE IN THE CLASSROOM
ACTIVITY
DESCRIPTION / METHODOLOGY / KEY QUESTIONS FOR SCAFFOLDING / LEARNING OBJECT/S
1 / Structure of a bacteria cell
Pupils explore the bacteria cell by their own (or in small groups) on a tablet or desktop computer.
Using a micro-module of type “picture information” pupils transfer the texts (technical term and explanation) into their own exercise books (mental modelling).
A real synthetic 3D model of a bacteria cell may help less able pupils to “grasp” bacterial structures.
In addition a foto album could overview the various shapes of bacteria cells (print-outs or pages of school book)
Predictions, what causes disease – structure or “behaviour” of the bacteria – can be recorded on IWB / Teachers moderates classroom activity and records predictions on IWB
Teacher focuses dialogue on the understanding, that the bacterial metabolism causes disease. / What are the main structures of a bacteria cell? What is the specific function of the structure?
What is the difference between bacteria cell and plant cell and / or animal cell?
What causes illness: A specific structure of the bacteria cell or a specific “behaviour”? /
The interactive picture information “modell of a bacteria cell” explores the characteristic features of a bacteria
[STRG]+Click on preview to navigate to online version
In first level of information, it shows technical terms. The second level the explanation. Pupils are able to assume the function of a structure and – in a second step - verify (or falsify) their assumption.
Interactive 3D model of
bacteria cell:
ACTIVITY
DESCRIPTION / METHODOLOGY / KEY QUESTIONS FOR SCAFFOLDING / LEARNING OBJECT/S
2 / Lifestyle of bacteria
Pupils work in small groups are trying to investige the exponential growth of a bacteria population.
Using a simulation (or step by step animation) pupils are able to change time period and the temperature of bacterial environment.
Simulation output is a picture (see illustration) and a graphical curve (cognitive flexibility > supplantation)
For advanced pupils a mathematical modelling is possible.
Besides the virtual simulation pupils can experience a “real” simulation by replaying the Persian fairytale “chessboard and rice corn). Pupils here should estimate how many doubling steps are needed to cover the whole chess board and predict whether one package of rice is enough to do so. / Inquiry based pupils activity, using simulation to predict, talk and discuss bacterial propagation. / What is the regularity of bacterial growth? Is it just a linear growing or an exponential growing?
What are the effects of time and temperature on bacterial growth?
Can bacterial growth be limited? /
3 / QUESTIONS FOR WHOLE CLASS DISCUSSION FOLLOWING LEARNING ACTIVITIES:
> See “Key Questioning for scaffolding”
ASSESSMENTMETHODS / Documentation in pupils exercise book (structure of bacteria)
Teacher questioning
Recorded teacher observation on IWB
DIFFERENTIATION / A plastic 3D modelto “grasp” and understand the bacterial structure
Replaying the fairytale “chessboard and rice corn”
Mathematical model for gifted pupils.
CREATOR / Steffen Schaal, Toni Cramer
RIGHTS / Creative Commons 3.0 (or use only, if resource from Klett Verlag)
ANNOTATION USER
ANNOTATION DESCRIPTION