Structure and Function of the Flower CXC Biology

Structure and Function of the Flower CXC Biology Syllabus Life Processes Specific Objectives 9. 6&9. 7 Andromeda Botanic Gardens Educational Series: #2

Section A: Flower Structure Science Objectives: Students should be able to • Recognize specified floral parts on most flowers • Relate each part to its function • Distinguish between staminate, pistillate/carpellate and hermaphrodite flowers Core Skills Objectives: • Co-operation/Group work • Drawing CXC Practical Skills • Drawing Andromeda Botanic Gardens Educational Series: #2

Structure and Function of the Flower Quiz #1 1. What is the male part of the flower called? --------------------------------------------2. What is the main function of a flower? --------------------------------------------3. What is the function of the carpel? --------------------------------------------4. Give one example of a hermaphrodite flower --------------------------------------------5. Name the flower structures which protect the young flower bud. --------------------------------------------Andromeda Botanic Gardens Educational Series: #2 -

Use the following to label the flower diagram below: Style, stamen, sepal, filament, peduncle, ovary, anther, receptacle, carpel, stigma, petal, ovule. Andromeda Botanic Gardens Educational Series: #2

What is a Flower? • Plant organ for sexual reproduction • Flowers produce gametes (sex cells) • Flowers are necessary for fertilisation to occur Andromeda Botanic Gardens Educational Series: #2

Flower Diagram Andromeda Botanic Gardens Educational Series: #2

Parts of the Flower • • • Peduncle: flower stalk Receptacle: part of stalk bearing the floral organs, at base of flower Sepal: leaflike structures at flower base, protects young flower bud Calyx: all the sepals together form the calyx Petal: located inside and above the sepals, often large and colourful, sometimes scented, sometimes producing nectar Stamen: male part of the flower, consist of the anther and filament, makes pollen grains Pollen: grains containing the male gametes Pistil/Carpel: female part of the flower, consist of the stigma, style and ovary Ovule: located in the ovaries, carry female gametes Staminate flower: flower bearing only male parts Pistillate/Carpellate flower: flower bearing only female sex parts Hermaphrodite flower: flower bearing both male and female sex parts Andromeda Botanic Gardens Educational Series: #2

Method 1. • • 2. 3. 4. 5. Collect specimens of the following flowers (your guide will show you where and which flowers to collect!) Pride of Barbados Hibiscus Orchid Flower of choice Make a labeled drawing of the Pride of Barbados and Hibiscus flowers (use the flower diagram as a guide, include magnification, labels in script) Dissect the Pride of Barbados flower ( a demonstration will be given) Make individual drawings of the petals, sepals, stamens, and pistils/carpels Dissect the pistil/carpel and make a labeled drawing of the ovary and the ovules lying within it Andromeda Botanic Gardens Educational Series: #2

Section B Pollination Science Objectives: Students should be able to: • Define pollination • State the main ways in which plants achieve pollination • Recognize flower adaptations associated with each mode of pollination Core Skills targeted • Drawing • Information Technology CXC Practical Skills • Analysis and Interpretation • Drawing Andromeda Botanic Gardens Educational Series: #2

Mode of Pollination 1. • • 2. Insect-pollinated flowers may have: Brightly coloured petals Strong sweet fragrance Nectar producing glands Guidelines to lead insects to Nectar • Large stigmas outside the flower • Little or no fragrance • Light non-sticky pollen • Lack showy petals 3. Bird-pollinated flowers may have: • Long tube shaped flowers • Bright red and yellow flowers • No odour Wind-pollinated flowers may have: Andromeda Botanic Gardens Educational Series: #2

Mode of Pollination (Continued) 4. • Mammal-pollinated flowers may have: White flowers • Strong fruity odour • Flowers opening at night 5. Water-pollinated flowers may have: • Pollen which floats on water (this form of pollination is rare) Andromeda Botanic Gardens Educational Series: #2

Method 1. • • • 2. 3. 4. Research and define the following terms in the Iris Bannochie library and on the Internet Pollination Self-pollination Cross-pollination Note the ways in which pollination may occur Identify the various adaptations associated with each form of pollination Collect flower specimens from the gardens and determine their method of pollination through completion of the Mode of Pollination Table Andromeda Botanic Gardens Educational Series: #2

Flower Name Light nonsticky Pollen Mode of Pollination Table Sticky Pollen Tube Shaped Mode of Pollination Colourful Petals Sweet Scented ü denotes a positive response Andromeda Botanic Gardens Educational Series: #2

Assessment Scheme for Drawing Element Criteria Sub-Total Clarity Clean continuous lines of even thickness No shading or unnecessary detail Reasonable size Any 3=2 Total 2 marks Any 2=1 Accuracy Faithfulness of reproduction 1 Structures typical of specimen included 1 3 marks Reasonable proportions 1 Labeling/ Labeling lines Neat drawn with a ruler; in pencil; not crossing No arrowheads; touching labeled structure 1 Labels in script 1 2 marks Labels accurate 1 mark Acceptable title Accurate description of specimen In caps Below drawing Magnification 1 mark Total 10 marks Any 2=1 Andromeda Botanic Gardens Educational Series: #2 1 mark

Use the following to label the flower diagram below: Style, stamen, sepal, filament, peduncle, ovary, anther, receptacle, carpel, stigma, petal, ovule. Andromeda Botanic Gardens Educational Series: #2

Structure and Function of the Flower Quiz #2 Pollination 1. Write a short definition for the word pollination. 2. Why is pollination important to plants? 3. State three ways in which pollination can be achieved. 4. State a plant adaptation associated with each mode of pollination above Andromeda Botanic Gardens Educational Series: #2

Analysis and Interpretation of the Pollination Exercise Background Information/Biological principles. (3 marks) Relationship to Investigation/Observation. • State the significance of pollination • Identify the flower structures which play the key role in pollination • Note how these structures are adapted to their role Explanation/Interpretations of result. (3 -4 marks) • Give reasons for interpretation of specified result Conclusion based on observation/data Related to Aim (2 marks) • Correct conclusions drawn Limitations (1 -2 marks) • Limitations of the results/conclusions stated Andromeda Botanic Gardens Educational Series: #2