Boundaries of Ecosystem

Boundaries of Ecosystem

Introduction to the Boundaries of an Ecosystem: This unit makes the ecosystem a specific entity (system). Boundaries of ecosystems are features of any entity. The ecological boundaries or boundaries of an ecosystem are the “outer envelope of an ecological entity such as individual, species, population, community or an ecosystem”. Cadenasso (2003) called them “the zone…

Origin of Heterospory and Seed Habit in Pteridophytes – BotanyLive
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Origin of Heterospory and Seed Habit in Pteridophytes – BotanyLive

We need to know about seeds and conditions for heterospory and seed habit. What is a seed? A seed is a “miniature plant, in-house plant, and a ripened ovule”. A seed consists of the embryo (young plant), stored food (cotyledon), and a seed coat (covering). These seed plants have an adaptive advantage. They occur in…

Cycadales/Cycads: Introduction, Origin, Characters, and Affinities

Cycadales/Cycads: Introduction, Origin, Characters, and Affinities

Introduction to Cycadales: Cycadales or cycads “living fossils” are member of gymnosperms (naked seeded plants). This group consists of 11 living genera and more than 100 species. This group contains both extinct and living (extant) genera. They dominated the world in the Jurassic period. These are present in tropical, subtropical, and warm temperate regions of…

Top 9 Density Dependent and Density Independent Factors
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Top 9 Density Dependent and Density Independent Factors

Density Dependent and Density Independent Factors Demography is the study of all the possible statistics that affect the size of a population. Some biotic and abiotic factors limit the size of a population. These factors are broadly categorized into density dependent and density independent factors. Density Dependent Factors: A factor that affects the size of…

Bennettitales: Introduction, Origin, Features and Affinities

Bennettitales: Introduction, Origin, Features and Affinities

Introduction and Origin of Bennettitales: The name “Bennettitales” has been given to honor J.J. Bennett, an English botanist. This group of fossil plants flourished well during the Triassic to Lower Cretaceous periods of the Mesozoic era (ages of Cycads). Palaeobotanists believe that this group originated from Pteridospermales. Fossils of Bennettitales are found either in the…

What are Angiosperms? Their features, distribution, and economic importance

What are Angiosperms? Their features, distribution, and economic importance

Introduction to Angiosperms The word angiosperm came from the Greek words; “Angeion”, containers, receptacle, or vessel, and “Sperma”, seed. Angiosperms are seed-bearing vascular plants that produce flowers, fruits, and seeds. After fertilization, ovules are not shed and remain enclosed within the ovaries. This group is the most diverse and the largest with 68 orders, 416 families,…

Ginkgo (Ginkgo biloba): Features, Morphology, Anatomy and Affinities

Ginkgo (Ginkgo biloba): Features, Morphology, Anatomy and Affinities

Taxonomic status of Ginkgo biloba: Kingdom Plantae Phylum Ginkgophyta Class Ginkopsida Order Ginkgoales Family Ginkgoaceae Genus Ginkgo Specie G.biloba Binomial Name: Ginkgo biloba Photo by Kanduri on pexels.com History Ginkgo biloba, a species from the gymnosperm group is native to China and Japan. Ginkgo has been planted since ancient times (about 1500 years ago) in…

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Life History Pattern and Resource Allocation

Life History Pattern The life history pattern of an organism is “the pattern of its survival and reproduction events during its life”. The traits that are studied in life history pattern includes morphological features like biomass, growth rate, size, phonological events, age at maturity, and reproductive features like fecundity (ability to produce new offspring), schedule…

Heterospory in Pteridophytes || Origin and Importance
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Heterospory in Pteridophytes || Origin and Importance

Heterospory in Pteridophytes Pteridophytes serve as a link between bryophytes and seed plants. In Pteridophytes, heterospory was reported in the late Devonian period. They are vascular plants with roots, stems, and leaves but no flower or seed. Most of the Pteridophytes are homosporous as they produce only one kind of spore. In homospory, the sex…