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VI. Read the text without the dictionary and express the main its idea.

Gymnosperms have seeds but not fruits or flowers. Gymnos means naked, sperm means seed: gymnosperm = naked seeds. Gymnosperms developed during the Paleozoic Era and became dominant during the early Mesozoic Era. There are 700 living species placed into four divisions: conifers, cycads, ginkgos, and gnetales (such as Ephedra).

The ginkgos also were a much more prominent group in the past than they are today. The sole survivor of this once robust and diverse group is Ginkgo biloba, the maidenhair tree. Extensively used as an ornamental plant, Ginkgo was thought extinct in the wild until it was discovered growing natively in a remote area of China. Ginkos are dioecious, with separate male and female plants. The males are more commonly planted since the females produce seeds that have a nasty odor. Pollination is by wind. Recently, Ginkgo has become the current herbal rave.

 

VII. Read the following text and answer the questions:

1. What is taxonomy?

2. What is the difference between Carolus Linneuss and Robert Whittakers classification of organisms?

3. What system do the most biologists employ now?

Taxonomy is that branch of biology dealing with the identification and naming of organisms. The ancient Greek philosopher Aristotle apparently began the discussion on taxonomy. British naturalist John Ray is credited with revising the concept of naming and describing organisms. During the 1700s, Swedish botanist Carolus Linneus classified all then-known organisms into two large groups: the kingdoms Plantae and Animalia. Robert Whittaker in 1969 proposed five kingdoms: Plantae, Animalia, Fungi, Protista, and Bacteria. Other schemes involving an even greater number of kingdoms have lately been proposed, however most biologists employ Whittaker's five kingdoms.

 

VIII. Translate this text into English.

1., , , . 2. () , 25. 3. , , , , (divisio, hylum); (classis), (ordo), (familia), (genus), (species).4. , , , , -(sub). 5., (subdivisio), (subclassis), (subfamilia), (subgenus) .

IX. Using the text The Plant Kingdom and exercises VII and VIII complete the following table and explain the organisms classification employing Whittakers five kingdoms.

KINGDOMS

BACTERIA  
? Algae Protozoans
FUNGI Zygomycota Basidiomycota
? Nonvascular Seedless Bryophyta  
Vascular Seedless Pretophyta
Vascular Seed Gymnosperms Coniferophyta
Ginkgophyta
? Anthophyta
Monocotyledones
?
ANIMALIA  

X. Read the text without the dictionary and answer the following questions:

1. What plants were the first on our planet?

2. Why are ferns, club-mosses, and horsetails called as the seedless vascular plants?

3. What is the difference between gymnosperms and angiosperms?

4. What does "Gymnos" mean?

5. What does angio mean?

6. What main parts are seeds composed of?

7. What are the main groups of angiosperms?

 

PLANT EVOLUTION

 

The first terrestrial plants to evolve, over 400 million years ago during the Paleozoic, were Bryophytes such as mosses (o). These show some of the first adaptations to land, including a waxy cuticle and enclosed gametangia (structures which produce gametes ( ) for sexual reproduction). All other plants developed vascular tissue, which transports water and nutrients throughout the plant.

The seedless vascular plantsinclude ferns (), club-mosses (), and horsetails (). They reproduce by spores and have vascular tissues. All other plants developed seeds for reproduction.

The gymnosperms include conifers and cycads. Gymnosperms have vascular tissue and reproduce with seeds. "Gymnos" means "naked" in Greek, and the seeds of gymnosperms do not have a special chamber enclosing them, in contrast with the angiosperms. Christmas trees, which are usually spruce () or pine (pine is the "no-shed" Christmas tree), are conifers.

The angiosperms, or flowering plants, include most obvious plants, from an oak () tree to the pansies (). Angio means container in Greek, and the angiosperms have developed flowers around the protective chamber called the ovary which, when the egg is fertilized, produces the seed. Seeds are composed of an embryo together with a food supply for its early development, inside a protective seed coat. Seed coats protect the embryo from threats such as drought and fire, and some species seeds can remain viable (able to develop) for many years in the soil.

Angiosperms also have vascular tissue. This group, which numbers about 235,000 species, is further divided into monocots, such as daffodils, grass, and tropical palm trees, and dicots (or eudichots), such as beech trees, violets, and daisies.

 

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