Course: AQA AS Biology Unit 2 Variety of Living Organisms Duration: 1 hour 30

Aims: investigating what variation is and how it is measured Previous Knowledge: GCSE science/biology

Learning Objectives

All students will know: that variation exists between members of the same species and this is intraspecific variationinterspecific variation is variation that occurs between different speciesenvironmental and genetic factors contribute to causing variation

Most students will know: that genotype refers to the genetic traits and phenotype refers to physical traitsthe difference between continuous and discontinuous variationwhat normal distribution looks like

Some students will: consider some intraspecific traits of people that could be investigated for variation and the possible causes for them

Timing Content/Skills Development Teaching and Learning Activities

Settler 5 - 10 Thunk: Thinking skills - what is variation why is it that even though people are all of the same species, we all look so very different?introduce the idea of intraspecific variation

Starter 15-20 building up glossary of key terms, definition: what is variation pair-group-class definition compare to ʻtextbook answerʼ

develop student glossary with the terms intraspecific and interspecific (analogy to internet/intranet)

know-want-learn grid brainstorm with students what they already know and want to learn, revisit this at the end of the chapter before the end of chapter test

AS Biology Variation Lesson One

Timing Content/Skills Development Teaching and Learning Activities

Main 45 What causes variation? introducing the terms genotype and phenotype

if time permits continuous and discontinuous data and normal distribution

how confident can we be in saying one thing causes the variation?

causes of variationpresent: terms phenotype and genotype, idea that some traits are environmental and some are genetic. Give example of genetic and example of environmentalaction: students to sort through some examples and place them onto venn diagrams (A3 - A5 for individuals)review: volunteer student to go through answers on visualiser, class discussion and justification

continuous and discontinuous data - A/B/AB/O blood groups vs. height, how could we present this data in a graph, one is continuous and one is discontinuous - which is which? can we summarise this in a diagram?

confidence in the causes of variationpresent: give students the idea that height is not just genetic, example of on average a mean lower height in some nations related to diet (compare two graphs)action: Give students another example of variation (hair colour?) and ask what is the cause of this. Is it genetic or environmental? How confident are they that this is the case? place these onto a confidence scale on the board (also on the back of their venn diagrams)review: Why can we not always be confident that there is just one cause to variation? how would we answer this question in an examination?

AS Biology Variation Lesson One

Timing Content/Skills Development Teaching and Learning Activities

Plenary 15-20 Plenary making notesstudents to make notes under a number of headings1. what is variation2. what causes variation3. how confident we can be about the causes

of variationQuestion for Thursdays lessons thunk: When studying variation, often twins are used. Why?

no homework set for this lesson

Extension For those who progress more quickly is your hair colour genetic? environmental or both? why? argument map of hair colour variationWhat is the hair colour variety in the classroom? how could you choose a random sample of students from the AS biology students?

AS Biology Variation Lesson One