botany: plant diversity Flashcards
From what are all plants thought to have evolved?
Simple unicellular algae.
What are the four major divisions of land plants?
Bryophyta, Pteridophyta, Gymnospermae (Gymnosperms), and Angiospermae (Angiosperms).
What features do all plants in the Kingdom Plantae share?
They are multicellular, eukaryotic, have cell walls made of cellulose, and perform photosynthesis with chloroplasts.
What is the alternation of generations in plants?
A life cycle with a spore-producing generation (sporophyte) and a gamete-producing generation (gametophyte).
What type of plants are Bryophyta?
Non-vascular plants like mosses, liverworts, and hornworts.
Where are Bryophytes commonly found?
In damp, shady areas.
How do Bryophytes reproduce?
Through spores produced in a structure called a sporophyte.
What anchors Bryophytes to a surface?
Rhizoids, not true roots.
What are the identifying features of Bryophyta?
Small size, leafy or flat thallus, and a distinctive sporophyte with a capsule at the end.
What plants are included in Pteridophyta?
Ferns.
What is the structure of a fern leaf called?
A frond, often divided into smaller leaflets.
How do ferns reproduce?
They produce spores in sporangia arranged in sori under the fronds.
What are the identifying features of Pteridophyta?
Horizontal rhizome, fronds, and sori (spore pouches) on the underside of fronds.
What are examples of Gymnosperms?
Cycads, ginkgos, conifers, and Gnetales (e.g., Welwitschia).
How do Gymnosperms reproduce?
By producing seeds on exposed scales of cones, with pollen carried by wind.
Do Gymnosperms have flowers?
No, they produce male and female cones instead.
What are the identifying features of Gymnospermae?
Needle or scale-like leaves, cones for seeds, and a strong root system.
What distinguishes Angiosperms from Gymnosperms?
Angiosperms produce seeds protected by fruit and have flowers instead of cones.
What are the two main groups of Angiosperms?
Monocotyledons (monocots) and Dicotyledons (dicots).
What are the identifying features of Angiosperms?
Flowers with pollen and ovules, fruit with seeds, and true roots, stems, and leaves with xylem and phloem.
How can you identify a monocot?
By one cotyledon, fibrous roots, herbaceous stems, parallel leaf veins, and floral parts in 3s or multiples of 3.
How can you identify a dicot?
By two cotyledons, a taproot, herbaceous or woody stems, branched leaf veins, and floral parts in 4s or 5s.
What type of root system does a monocot have?
A fibrous root system.
What type of root system does a dicot have?
A taproot system.
