Vascular Plants John Dennis

Vascular Plants  Vascular plants are plants that contain lignified tissues.  This helps conduct water, minerals, and photosynthetic products through the plants.  Some vascular plants include club mosses, ferns, gymnosperms and angiosperms.

Characteristics  Vascular plants contain vascular tissues which helps circulate important resources through the plant.  Having this feature allows them to grow a larger size than non-vascular plants which lack these tissues.  The principle generation phase in vascular plants is sporophyte, which is usually diploid meaning that it contains two chromosomes per cell.

Characteristics Cont.  Water transport either happens in either xylem or phloem. The xylem carries water and inorganic solutes up towards the leaves from the roots, while phloem carries organic solutes throughout the plant.

Angiosperms  Angiosperms (flowering plants) are the most diverse group of land plants.  Angiosperms produce seeds just like gymnosperms but can be distinguished from them by a series of characteristics.  These are: flowers, endosperm within the seeds, and the production of fruits that contain seeds.

Gymnosperms  Gymnosperms are a group of seed-producing plants.  The term “gymnosperm” comes from the Greek word gymnospermos which means “naked seeds.”  Their naked condition is what makes them different from angiosperms.  An angiosperm’s seeds and ovules are enclosed within an ovary.

Nutrient Distribution  Nutrients throughout vascular plants are distributed through two ways: The xylem and phloem.  The xylem takes water and nutrients from the roots to the upper sections of the plant’s body.  The phloem conducts materials, such as the sucrose during photosynthesis which gives the plants energy to keep growing and seeding.

Nutrient Distribution Cont.  The xylem consists of tracheids which are dead hard hollow cells that are arranged to form tiny tubes that serve as transportation for water.  A trachied cell wall usually contains the polymer lignin  On the other hand, the phloem contains living cells called sieve-tube members which are mainly to transport sugars up and down the plant.  Between the sieve-tube members are sieve plates which contain pores that allow molecules to pass through.  Sieve-tube members lack organs such as, nuclei and ribosomes but they have cells next to them, companion cells, which keep them alive.

Pictures

References  Google.com  Wikipedia.com