Plant KingdomBiology 112

Vascular Plants Moss-like plants evolved into more

complex structures that contained vascular tissue

Specialized cells to conduct water and nutrients throughout the plant

Considered to be a transport system

Transport Main component of xylem – the major

subsystem of plants that transport water from its roots to all parts of the plant

Hollow cells with thick cell walls that resist pressure

Phloem transports nutrients to all parts of the plant

Both can move fluids, even against the pressure of gravity

Ferns and their relatives Have true roots, stems and leaves Roots absorb water and nutrients and

water Stems support the plant and connect

the roots to the leaves as well as carry water and nutrients

Leaves are photosynthetic organs that contain one or more bundles of vascular tissue

Ferns

Contain vascular tissues, roots, creeping or underground stems called rhizomes and large leaves called fronds

Club Mosses

Responsible for the Earth’s first forests

Today, small plants that live among larger trees

Horsetails

Rare Only existing

genus contains nonphotosynthetic leaves arranged in whorls joined along the stem

Seed Plants Two major classifications

Gymnosperms Bear seeds directly on the surfaces of cones Ex. Conifers such as pines and spruces

Angiosperms Also referred to as flowering plants Bear their seeds within a layer of tissue that

protects the seed Ex. Grasses, flowering shrubs and trees,

wildflowers

Seed Plants - Reproduction

They can live in both aquatic and land environments

Such plants have either cones or flowers, the transfer of sperm through pollination, and the protection of embryos in seeds

Exhibit both a sporophyte as well as gametophyte stage

Seeds do not require water for fertilization

Cones and Flowers

Cones are sporophyte structures

Flowers are angiosperm structures

Allow seeds to develop

Pollen

Male gametophyte is contained in a pollen grain

Carried by wind, water or insects to the female structure

Seeds The embryo of a

plant Represents the

early stage of the sporophyte reproductive cycle

Seed coat protects the embryo and prevents it from drying out

Benefits of Being a Seed Plant The seed can survive environmental

conditions that ferns and mosses cannot Such plants can only survive in wet

conditions As the planet evolved, plants needed to

adapt to changing climatic conditions Seed plants represent a large group that

are found in all forests and swamps of North America

Gymnosperms

Such plants produce seeds that are exposed

Conifers

The most common group of gymnosperms

Otherwise known as evergreens

They do not lose their leaves all at once