Plant Adaptive Modifications

By now, you should be familiar with the basic structures of plants… Roots Stem Leaves Seeds Flowers (only in angiosperms) Fruit (only in angiosperms)

So where do these fit in?

Plant Modifications Evolution has allowed for the modification from the basic plant structures you have already learned.

Example 1:What do you think the following are the modified versions of? Onions, garlic, and other bulbs

What do you think the following are the modified versions of? Thorns

What do you think the following are the modified versions of? Tendrils

Example 1: Make a prediction Record in your notebook what modified part of a plant these might be.

Bulbs (like onions and garlic), thorns, and tendrils are all examples of modified shoots (stems and leaves). Bulbs: These shoots are an adaptation for interrupted life....for existence in environments with a dormant season due to annual rainfall variations or to life in the temperate climates. Thorns: Needed for protection against predation Tendrils: Tendrils of grape are modified flowering shoots. Shoots

What do you think the following are the modified versions of?

Example 2: Make a prediction Record in your notebook what modified part of a plant these might be.

Stems These are actually all examples of modified stems (not leaves). Succulent/photosynthetic Stems: In extremely dry environments, often the leaf becomes reduced and non-photosynthetic, and the stem becomes the primary photosynthetic organ of the plant. A barrel shape provides a low surface to volume ratio which reduces water loss.

What do you think the following are the modified versions of?

Example 3: Make a prediction Record in your notebook what modified part of a plant these might be.

Leaves Spines for Defense: The non-photosynthetic leaves of cacti have become modified for defense. Pitcher Plants: These are adapted for life in marshy/boggy nitrogen poor soil. The leaves are passive but lethal to insects. Venus Fly Traps and Sundew: These are in the same family. They are adapted for life in wet nitrogen poor soils and both entrap insects. Pine Needles

What do you think the following are the modified versions of?

Example 4: Make a prediction Record in your notebook what modified part of a plant these might be.

Roots Aerial roots are roots above the ground. They are almost always adventitious. They are found in diverse plant species, including epiphytes such as orchids, tropical coastal swamp trees such as mangroves, the resourceful banyan trees, the warm-temperate rainforest.

Wild Orchid Wasp Mimic

Video Questions Answer these questions in your notebook please! 1. What two strategies has the orchid adapted to attract the wasps? 2. What is the benefit of these adaptations to the orchid 3. Come up with a hypothesis for how the wasp might evolve to avoid how the orchid essentially “tricks” the wasp.