UNIT ____: Angiosperm Reproduction                          Name: ________________________

Essential Idea(s):

Reproduction in flowering plants is influenced by the biotic and abiotic environments.

IB Assessment Statements and Class Objectives

9.4.S2:  Drawing of half-views of animal-pollinated flowers.

• Draw and label an animal pollinated flower, including:

• Nectar-secreting glands
• Petals
• Sepals
• Stamen
• Anthers
• Filaments
• Pistil
• Stigma
• Style
• Ovary
• Ovule

• State the function of the different parts of the animal-pollinated flower.

9.4.U1:  Flowering involves a change in gene expression in the shoot apex.

• List the vegetative and reproductive structures of an angiospermatophyta.
• State that flowers are produced from a shoot apical meristem.
• State two abiotic factors that may trigger flowering.
• Compare the timing of flowering in short-day plants and long-day plants.
• Outline the process by which changes in gene expression trigger flowering.

9.4.U2:  The switch to flowering is a response to the length of light and dark periods in many plants.

• State the role of the pigment phytochrome.
• Describe the conversions between the two forms of phytochrome.
• Describe role of phytochrome in controlling flowering in long and short day plants.

9.4.A1:  Methods used to induce short-day plants to flower out of season.

• State how plants can be manipulated to force flowering out of season.

9.4.U3:  Success in plant reproduction depends on pollination, fertilization and seed dispersal.

• Define pollination, fertilization and seed dispersal.
• State the changes to the ovule and ovary that result from fertilization.
• List mechanisms of seed dispersal.

9.4.S1:  Drawing internal structure of seeds

• Draw and label the structure of seeds, including:

• Embryo root
• Embryo shoot
• Cotyledons
• Testa
• Micropyle
• Hilum

• State the function of the different parts of the seed.

9.4.S3:  Design of experiments to test hypothesis about factors affecting germination.

• Define germination.
• Outline why water, oxygen and warmth are required for germination.
• Outline the role of gibberellin during germination.
• Write five example problem questions for experiments that could test factors affecting germination.

Review:  Major Plant Phyla

Flower Structure

Flower Structure Functions

Control of Flowering

Flowering is affected by external factors:

• light
• temperature
• moisture

And internal factors:

• phytochrome
• florigen hormone
• genes involved in plant flowering regulation

Flowers form from differentiation of cells in shoot apical meristems.

Phytochrome

Photoperiods

After fertilization:

• ovules develop into seeds

• ovary develops into a fruit

Seed Dispersal

Seed Structure

Germination