Relative dating concept
Although many conservative references place the archaebacteria in a separate division within the kingdom Monera, most authorities now recognize them as a 6th kingdom--The kingdom Archaebacteria.In fact, data from DNA and RNA comparisons indicate that archaebacteria are so different that they should not even be classified with bacteria. The scalelike leaves of Arizona cypress are glaucous and very glandular (sticky).In eukaryotic cells, the initial messenger RNA (M-RNA) transcribed from the DNA (gene) is modified (shortened) before it leaves the nucleus.Sections of the M-RNA strand called introns are removed, and the remaining portions called exons are spliced together to form a shortened (edited) strand of mature M-RNA that leaves the nucleus and travels to the ribosome for translation into protein.Although the Kingdom Protista includes mostly unicellular organisms, the WAYNE'S WORD staff feels that these algal divisions belong in the Kingdom Protista (Protoctista) rather than the Kingdom Plantae.3. Another group of conifers with fleshy seed-bearing structures are the junipers (Juniperus) in the Cypress Family (Cupressaceae).Some members of the Kingdom Fungi (in the fungal classes Ascomycetes and Basidiomycetes) are associated with algal cells of the Kingdom Protista (in the algal division Chlorophtya) and/or prokaryotic cyanobacteria of the Kingdom Monera. Junipers actually produce small cones with fleshy, fused scales bearing one-several seeds.There are approximately 1.6 million species of living organisms on earth. California nutmeg (Torreya californica), a member of the Division Coniferophyta, Order Taxales, Family Taxaceae.This number may be much higher because new species are continually being discovered each day, particularly insects and nematodes in remote tropical regions. Like Podocarpus, the "naked" seed is enclosed in a fleshy, outer layer (called an aril) which superficially resembles a one-seeded fruit of an angiosperm.
In fact, some flattened protoctists discovered in the Ediacaran biota had characteristics resembling lichens. The seed has a hard coat surrounded by a fleshy outer layer (aril).Generally "animals" are subdivided into phyla, while "plants" are subdivided into divisions.These subdivisions are analogous to subdirectories or folders on your hard drive.They also place the macroscopic, multicellular brown algae (Division Phaeophyta) and red algae (Division Rhodophyta) in the Kingdom Plantae. In the latter species, the naked seed sits partially exposed in a red, cup-shaped aril.In fact, some authors place all of the algae divisions in the Kingdom Plantae. Podocarpus seeds are often referred to as fleshy fruits called drupes, but this is incorrect because drupes develop from the ovaries of flowering plants.