Life Science Grade 11

Grade 11 Life Sciences Lesson PlansGRADE 11 SUBJECT Life Sciences WEEK 7 TOPIC Characteristics of body plans – Symmetry and Tissue Layers Lesson 3LESSON SUMMARY FOR: DATESTARTED:LESSON OBJECTIVESDATECOMPLETED:Content: CAPS p41Key Features in respect of body plans:• Symmetry and cephalisation• The number of tissue layers developed from embryo.•The learner must be able to:• Discuss the three types of symmetry found in animals and give examples of animals displaying each type of symmetry• Understand how the germ layers form in an embryo• Describe the difference between diploblastic and triploblastic animals• Explain what each tissue layer gives rise to in a fully developed animal• Complete diagrams illustrating layers of tissue in developing embryosTEACHER ACTIVITIES LEARNER ACTIVITIES TIMING RESOURCES NEEDED1.1 Introduction• Pre – knowledge: a zygote is formed when fertilizationoccurs between a sperm and egg cell, mitosis leads tothe formation of different tissues and organs in the body• Use the blackboard or transparencies.• Refer back to the previous lesson and remind learnersthat a body plan for an animal includes morphologicaland developmental characteristics.• Remind learners that as a zygote begins to gothrough mitosis, more and more identical cells areformed.• These cells will later differentiate to form the differenttissues and organs of the body as the embryo develops2.2 Main Body (Lesson presentation)• The following must be highlighted by use ofblackboard/transparencies and class discussion:• Body plans of animals are characterised bysymmetry, number of tissue layers that develop from theembryo, the presence or absence of body cavities andthe presence or absence of a through gut• These characteristics help scientists classify animals• Symmetry refers to how the arrangement of bodyLearners listen to the discussion, askingand answering questions.Learners listen to discussion asking andanswering questions.10 min20 minUnderstanding Life Sciences p88Solutions for all p91Study and master p117Understanding Life Sciences p86-87Powerpoint internet presentation onsymmetry :http://alex.state.al.us/uploads/24073/Body%20Symmetry%20of%20Animals.ppt•Term 1 Page 62© Gauteng Department of Education (CAPS version)