Plant Diversity and Evolution Quiz

Plant Diversity

• Plants are multicellular eukaryotic organisms.
• Their cell walls are made of cellulose.
• Plants are autotrophic, meaning they produce their own food through photosynthesis.

Plant Life Cycles

• Plants, like protists and fungi, exhibit alternation of generations in their life cycles.
• They have both haploid and diploid stages.
• These stages have specific names in plants.
• Gametophyte: a haploid individual producing gametes.
• Sporophyte: a diploid individual producing haploid spores via meiosis.
• Spores grow into gametophytes, completing the cycle.

Plant Evolution

• The first plants evolved from algae.
• Algae live entirely in water, while plants adapted to live on land.
• Land plants needed three key adaptations:
  • Absorb nutrients from their surroundings. Plants evolved roots to do this.
  • Prevent water loss: Plants evolved a waxy, watertight covering called a cuticle.
  • Disperse themselves across dry land. This can happen by wind, water, or other organisms.

Plant Groups

• Plants evolved into four main groups. These are classified through nonvascular, seedless vascular, seed, and flowering.
• Ancestral green algae are their common ancestor.
• Seedless vascular plants include; Mosses, Liverworts, Hornworts, Lycophytes, Pterophytes (whisk ferns, ferns, horsetails, quillworts).
• Seed plants include Gymnosperms and Angiosperms.
  • Gymnosperms are cone-bearing, produce seeds without enclosing fruit.
  • Angiosperms are flowering plants that produce seeds enclosed within fruit.
  • Gymnosperm = “naked seed”
  • Angiosperm = “covered seed”

Seedless Plants

• Seedless plants are considered the most primitive type of plant.
• They are divided into two groups: nonvascular and vascular.

Nonvascular Plants (Bryophytes)

• Nonvascular plants lack vascular tissue (veins) for transporting water.
• Water travels through osmosis and diffusion, limiting their size.
• Examples include mosses, liverworts, and hornworts.

Vascular Plants

• Vascular plants contain vascular tissue for efficient transport of water and nutrients.
• This allows them to grow taller.
• Two types of vascular tissue:
  • Xylem: transports water.
  • Phloem: transports food (sugars and nutrients).

Seed Plants - Groups

• Seed plants are vascular and produce seeds to aid in their offspring's dispersal and survival.
• Classified into two main groups: gymnosperms and angiosperms.
• The key difference is how they develop their seeds (gymnosperms are "naked seeds" and angiosperms have a fruit enclosing their seeds).

Gymnosperms

• Gymnosperms are cone-bearing plants, including conifers.
• They do not have fruit enclosing their seeds.

Angiosperms

• Angiosperms reproduce using flowers, making them flowering plants.
• Their flowers attract insects and animals for pollination.
• Ovaries develop into fruit that aids in seed dispersal.
• Angiosperms are divided into two classes based on seed structure: monocots and dicots.

Classifying Angiosperms

• Monocots have one seed leaf (cotyledon).
• Dicots have two seed leaves.

Monocots vs. Dicots

• Monocots typically exhibit parallel venation (veins run parallel to each other in the leaves), while dicots have net venation (veins form a net pattern).
• Monocot flowers usually have parts in multiples of three, while dicots tend to have parts in multiples of four or five.
• Monocots typically have fibrous root systems, whereas dicots usually have a taproot.

Explore the fascinating world of plant life in this quiz on plant diversity, life cycles, and evolution. Understand the unique characteristics that define plants and their adaptation strategies for life on land. Test your knowledge on terms like gametophyte and sporophyte, and learn about the evolution of plants from algae.