Evolution & Adaptation
These are the two main groups of seed plants; one dominated the Mesozoic era, while the other comprises 90% of living plant species today.
What are Gymnosperms and Angiosperms?
The name "Gymnosperm" literally translates to this, referring to their seeds not being enclosed in ovaries.
What is "Naked Seed"?
This is the female reproductive organ of a flower, which consists of the stigma, style, and ovary.
What is the Carpel (or Pistil)?
This process occurs when a pollen grain lands on the stigma of a compatible flower.
What is Pollination?
Plants like dandelions use this abiotic method for seed dispersal.
What is Wind Dispersal?
Unlike mosses, seed plants have a life cycle dominated by this generation.
What is the Sporophyte?
Most gymnosperms are cone-bearing plants, also known by this name
What are Conifers?
These colorful modified leaves are used by flowers to attract pollinators.
What are Petals?
Angiosperms undergo this unique process where one sperm fertilizes the egg and another joins with two nuclei to form food-storing tissue.
What is Double Fertilization?
This structure grows down through the style to deliver sperm directly to the female gametophyte.
What is a Pollen Tube?
This term describes the production of two types of spores (megaspores and microspores) seen in all seed plants.
What is Heterospory?
This type of pollination is common in gymnosperms but less common in angiosperms, which usually rely on animals.
What is Abiotic (or Wind) pollination?
This floral structure consists of a stalk called a filament and an anther where pollen is produced.
What is the Stamen?
This triploid (3n) tissue provides nutrients to the developing embryo in angiosperm seeds.
What is Endosperm?
This waxy covering on the epidermis of land plants helps prevent desiccation (drying out).
What is the Cuticle?
A seed consists of an embryo and its food supply, both packaged within this protective layer.
What is a Seed Coat?
Within the anther, these specialized structures (also called microsporangia) produce the pollen grains.
What are Pollen Sacs?
After fertilization, the ovule develops into a seed, while the ovary wall thickens to become this.
What is a Fruit?
This term describes a seed that has stopped growing and has a very low metabolic rate, waiting for environmental cues to germinate
What is Dormancy?
The female gametangia, which produce a single non-motile egg, are called this.
What are Archegonia?
This large diploid cell undergoes meiosis to produce four haploid megaspores, though only one usually survives.
What is the Megasporocyte?
Each microspore undergoes mitosis to produce these two specific cells found within a pollen grain.
What are the Generative cell and the Tube cell?
These are the four specialized shoots (whorls) of a complete flower.
What are Sepals, Petals, Stamens, and Carpels?
Land plants evolved from this specific group of green algae.
What are Charophytes?
Bryophytes lack vascular tissue, meaning they must stay low to the ground and rely on this process to move water.
What is Diffusion?