Angiosperm vs Gymnosperm


Angiosperm vs Gymnosperm
Angiosperms and gymnosperms are types of vascular plants that produce seeds. Angiosperm seeds are enclosed, while gymnosperm seeds are not.

In biology, the angiosperms and gymnosperms are the two groups of vascular, seed-bearing plants. The term “angiosperm” comes from Greek words that mean “container seed,” while “gymnosperm” comes from the words for “naked seed.” A fruit encloses an angiosperm seed, while a gymnosperm seed lacks this coating. But, there are other distinctions between these groups. Here is a look at the differences between angiosperms and gymnosperms.

Gymnosperms

Gymnosperms appear in the fossil record about 319 million years ago. While not the first vascular plants, they were the first with pollen and seeds instead of spores. Seeds usually form within unisexual (separate male and female) strobili or cones. Pollen helped these plants spread genetic information across vast distances, while seeds protected the plant embryos and helped them survive until conditions were just right for germination. This helped gymnosperms expand into drier habitats.

Presently, there are around 1,000 gymnosperm species. They include pine, spruce, cedar, fir, yew, cypress, and cycads. Most of these species are conifers, which have needle-shaped leaves, are evergreen, and have soft wood. Gymnosperms remain successful in cold, dry environments. They are economically important as sources of resin and wood for lumber and paper. Gingko and pine nuts are edible examples of gymnosperms.

Angiosperms

Angiosperms did not appear in the fossil record until about 150 million years ago, but within 50 million years they became the dominant type of plant. Flowers attract pollinators and contain the reproductive structures of an angiosperm. Flowers are either unisexual (male and female flowers) or bisexual (both male and female parts on a single flower). Seeds develop within the flower’s ovary and are surrounded by an endosperm or fruit. Angiosperms co-evolved with animals. While gymnosperms are almost exclusively pollinated by wind, angiosperms use wind, water, and/or animals.

Around 80% of plants today are angiosperms. There are 300,000 species, which are classified as either monocots or dicots. Examples include rose, dandelion, daisy, oak, maple, Venus flytrap, wheat, apples, cherries, and potatoes. Angiosperms often have medicinal value and are a source of hardwood. Most edible plants are angiosperms.

Angiosperm Advantages

Flowering plants have some advantages compared with gymnosperms:

  • More efficient water and nutrient transport
  • Better nutrition for embryo
  • Better protection for embryo

Angiosperms have specialized cells called vessel elements that help them move water more quickly than in gymnosperms, which only have tracheids for moving water. Additionally, angiosperm phloem moves sugars more efficiently than in gymnosperm tissue. Angiosperms have double-fertilization that results in an endosperm around the seed that protects and nourishes it.

However, many angiosperms depend on insects or other animal pollinators. So, they are highly sensitive to the effects of species extinction.

Summary of Differences Between Angiosperms and Gymnosperms

Both angiosperms and gymnosperms are vascular plants that produce seeds. Both have a sporophyte-dominated life cycle, which means most of their life cycle they are diploid (2n), with a short gamete-producing phase. Here are the differences between them:

AngiospermsGymnosperms
Flowering plantsDo not produce flowers
Reproductive structures in flowersReproductive structures in cone
Seed enclosed in an ovary, which becomes a fruitNaked or unenclosed seeds
Usually have flattened leavesMost have needle-like or scale-like leaves
Have a seasonal life cycleEvergreen
Contain triploid (3n) tissue / double fertilizationContain haploid (1n) tissue / single fertilization
Herbaceous or else source of hardwoodSource of softwood
Often have animal pollinatorsAlmost exclusively wind-pollinated

References

  • Cantino, Philip D.; Doyle, James A.; et al. (August 2007). “Towards a phylogenetic nomenclature of Tracheophyta”. Taxon. 56 (3): 822–846. doi:10.2307/25065864
  • Heywood, V.H.; Brummitt, R.K.; et al. (2007). Flowering Plant Families of the World. Richmond Hill, Ontario, Canada: Firefly Books. ISBN 978-1-55407-206-4.
  • Morris, Jennifer L.; Puttick, Mark N.; et al. (2018). “The timescale of early land plant evolution”. Proceedings of the National Academy of Sciences of the United States of America. 115 (10): E2274–E2283. doi:10.1073/pnas.1719588115
  • Russell, Peter J.; Wolfe, Stephen L.; et al. (2008). Biology: The Dynamic Science (1st ed.). Brookes/Cole. ISBN: 978-0-534-24966-3.