1 Review the introduction to Lab topic 15 Plant Diversity I

1. Review the introduction to Lab topic 15, Plant Diversity I, and describe the major trends in the evolution of land plants.

Exercise 21.1 – Factors Influencing Seed Germination

1. What has happened to the endosperm that formed in the embryo sac of the developing ovule in Lab Topic 16, Plant Diversity II?

2. How have the cotyledons developed and from what? (Check your text; see, for example, Campbell and Reece, 2005, Chapter 38)

	1. Review the introduction to Lab topic 15, Plant Diversity I, and describe the major trends in the evolution of land plants.
Exercise 21.1 – Factors Influencing Seed Germination
	1. What has happened to the endosperm that formed in the embryo sac of the developing ovule in Lab Topic 16, Plant Diversity II?
	2. How have the cotyledons developed and from what? (Check your text; see, for example, Campbell and Reece, 2005, Chapter 38)

Table 15.5 Fruit Types and Dispersal Mechanisms plantName Fruit Type Dispersal Method

Solution

Table 15.5

Plant name

Fruit type

Dispersal method

Vitis vinifera

Berries (grapes)

Animal vectors(Birds)

Citrus limon

Hesperidium (lemon)

Animal vectors(Humans)

Terminalia catappa

Drupe (almond)

Animal vectors(squirrels)

Triticum aestivum

Caryopsis(wheat)

Wind

Pisum sativum

Pod(peas)

Ballistic mode(pressure)

1. Plant diversity:

Plants grow in different habitats. Based on that, they adopted vascular tissue and spore forming ability. As well they are diversified as vascular and non-vascular plants, bryophytes and pteridophytes.They adopt certain features during evolution to survive in different habitats. For example, roots for firm fixation in soils, leaves to manufacture food from the natural source, sporing plants to propagate, vascular tissue in highly evolved plants for the transport of food and water, and so on.

Trends in evolution of land plants

Plants show gradual evolution from non-vascular to vascular, bryophyta to pteridophytes accordingly.During Ordovician period, plants showed their existence. The development of roots, leaves, free sporing plants and plants with secondary vascular tissue, existed in Devonian age. This evolution is being continued from the carbon age and is going on still, which has to be revealed.

Plant name	Fruit type	Dispersal method
Vitis vinifera	Berries (grapes)	Animal vectors(Birds)
Citrus limon	Hesperidium (lemon)	Animal vectors(Humans)
Terminalia catappa	Drupe (almond)	Animal vectors(squirrels)
Triticum aestivum	Caryopsis(wheat)	Wind
Pisum sativum	Pod(peas)	Ballistic mode(pressure)