20 2 Classification of Plants KEY CONCEPT Plants

20. 2 Classification of Plants KEY CONCEPT Plants can be classified into nine phyla/divisions.

20. 2 Classification of Plants Land plants are classified by the presence or absence of vascular tissue and how they reproduce (with or without seeds) • “Vascular” – People: relating to vessels, especially those that carry blood. – Plants: relating to plant tissues that conduct water, sap, and nutrients.

20. 2 Classification of Plants Vascular Plants vs. Nonvascular Plants Vascular Nonvascular • Transport System – Leaves – True roots – Xylem – Phloem – Stems • Can grow tall • Live in dry areas • No Transport System – No roots (rhizoids) • Grow close to the ground to absorb water and nutrients • Live in moist areas *Complete Venn Diagram in notes

20. 2 Classification of Plants

20. 2 Classification of Plants Nonvascular Plants

20. 2 Classification of Plants Mosses and their relatives are seedless nonvascular plants. • Liverworts belong to phylum Hepatophyta. – often grow on wet rocks or in greenhouses – can be thallose or leafy

20. 2 Classification of Plants • Mosses belong to phylum Bryophyta. – most common seedless nonvascular plants – sphagnum moss commonly used by humans as “peat”

20. 2 Classification of Plants • Hornworts belong to phylum Anthocerophyta. – found in tropical forests and along streams – flat, lobed body with little green “horns”

20. 2 Classification of Plants Vascular Plants Seedless vs. w/Seeds

20. 2 Classification of Plants Club mosses and ferns are seedless vascular plants. • Club mosses belong to phylum Lycophyta. – not true mosses – oldest living group of vascular plants

20. 2 Classification of Plants • Ferns and their relatives belong to phylum Pterophyta. frond fiddlehead – whisk ferns and horsetails are close relatives of ferns – ferns have large leaves called fronds

20. 2 Classification of Plants Seed plants include cone-bearing plants and flowering plants. • Seed plants have several advantages over their seedless ancestors. – can reproduce without free-standing water, via pollination – seeds nourish and protect plant embryo – seeds allow plants to disperse to new places

20. 2 Classification of Plants • Gymnosperms do not have seeds enclosed in fruit. – most gymnosperms are cone-bearing. – the cone is reproductive structure of most gymnosperms. – pollen is produced in male cones. – eggs are produced in female cones. – seeds develop on scales of female cones.

20. 2 Classification of Plants • Cycads are gymnosperms in phylum Cycadophyta. – look like palm trees with large cones – grow in tropical areas

20. 2 Classification of Plants • Ginkgos are gymnosperms in phylum Ginkgophyta. – only one species alive today, Ginkgo biloba – grown in gardens and used in urban landscaping

20. 2 Classification of Plants • Conifers are gymnosperms in phylum Coniferophyta. – most common gymnosperms alive today – includes pines, spruce, cedar, fir, and juniper

20. 2 Classification of Plants • Angiosperms, or flowering plants, belong in phylum Anthophyta. • Angiosperms have seeds enclosed in some type of fruit. – A flower is the reproductive structure of angiosperms. – A fruit is a mature ovary of a flower.

20. 2 Classification of Plants Plant Classification Lab • Goal: Identify plants as either vascular or nonvascular based on microscope analysis. • This lab does not need to be a formal write up… only include the Title, Goal, and components listed below: – Draw image and label transport system components – Record slide name and number – Record as either vascular or nonvascular