Plant Evolution Pt. 1 Flashcards
What is the structure of byrophytes?
Never have roots, contain rhizoids, simple leaves and stems are non-vascular
What is the structure of filicinophytes?
Vascular roots, leaves & non-woody stems
What is the structure of conferophytes? (TNT)
Trees or shrubs with woody vascular tissues, narrow leaves with thick waxy cuticle
What is the structure of angiospermophytes?
Roots, leaves and stems, vascular tissue, some stems are herbaceous others woody
What adaptations of vascular plants has helped their success on land?
Roots stems and leaves. Structural support to stand on land. Vascular system. Pollen reduces water usage
Draw and label the distribution of tissues in the stem
Refer to image
Explain the relationship between the distribution of tissues in the leaf and the functions of these tissues
Epidermis on the outside: Stomata on underside of leaf; allows exchange of gases
Ground tissue: palisade parenchyma = site of most photosynthesis. Spongy parenchyma =
gases circulate.
Vascular tissue: branches into leaf traces for support and improved transport of water/nutrients
What are three characteristics of monocotyledonous plants?
embryos have one cotyledon, leaf has veins that are usually parallel, stems are vascular bundles usually complexly arranged
What are three characteristics of dicotyledonous plants? (TNR)
embryos have two cotyledons, leaves have veins that are usually netlike, and stems are vascular bundles usually arranged in a ring
What is the function of apical meristems in dicots?
Allow plant to grow in length and serves as the primary growth
What is the function of lateral meristems in dicots?
Allows the plant to grow in girth (stems in woody plants) serves as the secondary growth
Explain the role of auxin in phototropism as an example of the control of plant growth
Promotes elongation and forces stem to grows towards light
What is a storage organ?
A storage organ is a part of a plant specifically modified to store energy (e.g. carbohydrates) or water
Where are the storage organs in plants found?
They are usually found underground (better protection from herbivores) and may result from modifications to roots, stems or leaves:
What is a storage root?
Modified roots that store water or food (e.g. carrots)
What are stem tubers?
Horizontal underground stems that store carbohydrates (e.g. potato)
What are bulbs?
Modified leaf bases (may be found as underground vertical shoots) that contain layers called scales (e.g. onion)
How do succulents enable water storage?
modified leaves or stems (thickened, fleshy and wax-covered) to enable water storage
How do other plants modify to support climbing and attachment?
They have tendrils which enable climbing and attatchment
Outline four adaptations of xerophytes
small or compound leaves, deep root systems, spines, waxy cuticle development, and a variety of stomata adaptations.
State the significance of thickened cellulose in terrestrial plants
Thickening of the cell wall provides extra structural support
State the significance of cell turgor in terrestrial plants
Increased hydrostatic pressure within the cell exerts pressure on the cell wall, making cells turgid
State the significance of lignified xylem in terrestrial plants
Xylem vessels run the length of the stem and branches, lignification of these vessels provides extra support
Explain how the root system provides a large surface area for mineral ion and water uptake
Plants take in water and essential minerals through their roots; thus need a large surface area in order to optimize the uptake. The ‘extensive’ branching of the roots and the growth of root hairs allows for the plant to increase its mineral ion absorption and surface area of water.
List three ways in which mineral ions in the soil move to the root
Diffusion, mass flow, and fungal hyphae
