plant diversity Flashcards
(23 cards)
What are the three main phyla of plants?
Bryophytes, Pterophytes, Spermatophytes
Examples include mosses, ferns, and flowering plants.
What type of plants are gymnosperms?
Seed-bearing plants with ‘naked seeds’
Examples include cycads, conifers, and ginkgo.
What defines angiosperms?
Flowering plants
They produce seeds enclosed within a fruit.
In which order are the plant phyla arranged based on their adaptation to land?
From most primitive to least primitive
This order reflects their increasing ability to live on land.
What is the dominant generation in Pterophytes?
Sporophyte generation
Spores develop into heart-shaped gametophytes.
What is required for reproduction in Pterophytes?
Dependence on water
Male gametes swim to female gametes to form a zygote.
What type of leaves do Pterophytes have?
True leaves (fronds)
They also have a waxy cuticle and stomata.
What type of roots do Pterophytes possess?
True roots and adventitious roots at nodes of rhizomes
They also have root hairs.
What type of vascular tissue do Pterophytes contain?
Xylem and phloem
Xylem contains tracheids only.
Describe the reproductive structure of liverworts.
They grow flat along the ground on moist surfaces
They resemble a human liver.
What defines the gametophyte in bryophytes?
Dominant generation, produces spores
The sporophyte generation gives rise to the gametophyte.
What is the structure of the plant body in bryophytes?
Thallus
It does not develop into roots, stems, or leaves.
What are the four groups of plants categorized by?
Presence or absence of:
* True leaves
* True roots
* Vascular tissue
* Spores, seeds, or fruit
* Dependence on water for reproduction
What adaptations do most terrestrial plants require?
Ability to:
* Absorb water and minerals
* Be firmly attached to soil
* Reduce water loss
* Support themselves
What type of reproduction do gymnosperms utilize?
Cones
Male cones produce pollen grains.
How do angiosperms reproduce?
Through flowers
Flowers are modified leaves with structures like sepals, petals, stamens, and carpels.
What is a significant characteristic of gymnosperms regarding their vascular tissue?
Well-developed vascular tissue
Xylem contains tracheids only and has cambium for secondary thickening.
What is the role of pollen grains in gymnosperms?
Dispersed by wind to form a pollen tube
This allows male and female gametes to fuse.
True or False: Angiosperms are independent of water for reproduction.
True
Mature pollen grains land on a stigma to form a pollen tube.
What type of leaves do angiosperms have?
Well-adapted true leaves
They are suited for terrestrial survival.
What distinguishes the roots of angiosperms?
Well-developed true roots with root caps and root hairs
This increases surface area for absorption.
What is the composition of the vascular tissue in angiosperms?
Well-developed xylem and phloem
Xylem consists of vessels and tracheids; phloem has sieve tubes and companion cells.
