Saturday, 30 June 2012
Hepatics or Liverworts
The **Marchantiophyta are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryophytes, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information. It is estimated that there are 6,000 to 8,000 species of liverworts, though when neotropical regions are better studied this number may approach 10,000. Some of the more familiar species grow as a flattened leafless thallus, but most species are leafy with a form very much like a flattened moss. Leafy species can be distinguished from the apparently similar mosses on the basis of a number of features, including their single-celled rhizoids. Leafy liverworts also differ from most (but not all) mosses in that their leaves never have a costa (present in many mosses) and may bear marginal cilia (very rare in mosses). Other differences are not universal for all mosses and liverworts, but the occurrence of leaves arranged in three ranks, the presence of deep lobes or segmented leaves, or a lack of clearly differentiated stem and leaves all point to the plant being a liverwort. Liverworts are typically small, usually from 2–20 mm wide with individual plants less than 10 cm long, and are therefore often overlooked. Certain species may cover large patches of ground, rocks, trees or any other reasonably firm substrate on which they occur. They are distributed globally in almost every available habitat, most often in humid locations although there are desert and arctic species as well.
Angiosperms
The flowering plants or angiosperms, (also known as Angiospermae or Magnoliophyta), are the most diverse group of land plants. They are are seed-producing plants - like the gymnosperms - but can be distinguished from the gymnosperms by a series of synapomorphies (derived characteristics). These characteristics include flowers, endosperm within the seeds, and the production of fruits that contain the seeds. The ancestors of flowering plants probably diverged from gymnosperms around 245–200 million years ago, and the first flowering plants known to exist are from 140 million years ago. They diversified enormously during the Lower Cretaceous and became widespread around 100 million years ago, but replaced conifers as the dominant trees only around 60–100 million years ago. Flowers are the reproductive organs of flowering plants, and are the most remarkable feature distinguishing them from other seed plants and endow angiosperms by enabling a wider range of adaptability and broadening the ecological niches open to them. This has allowed flowering plants to largely dominate most terrestrial ecosystems.
Stamens are the pollen-producing reproductive organs of a flower, typically consisting of a stalk and an anther, which contains microsporangia - typically four microsporangia - which form sacs (locules) in the anther. Each microsporangium is lined with a nutritive tissue layer called the tapetum and initially contains diploid pollen mother cells. These undergo meiosis to form haploid spores. Each microspore then divides mitotically to form an immature microgametophyte called a pollen grain. The pollen is eventually released by the opening - or dehiscence - of the anther. When ready, the pollen is carried by some external agent (wind, water or some member of the animal kingdom) to the receptive surface of the carpel of the same or another flower. This process is known as pollination. After successful pollination, the pollen grain (immature microgametophyte) completes its development by growing a pollen tube and undergoing mitosis.
A flower is called an androecium. The androecium forms a whorl surrounding the gynoecium (carpels) and inside the perianth (the petals and sepals together) if there is one. Stamens can be free or fused in various ways. A column formed from the fusion of multiple filaments is known as an androphore. Stamens have become modified through time which prevents self-fertilization, producing further diversification, allowing angiosperms eventually to fill more niches. The closed carpel of angiosperms also allows adaptations to specialized pollination syndromes and controls. This helps to prevent self-fertilization, thereby maintaining increased diversity. Once the ovary is fertilized, the carpel and some surrounding tissues develop into a fruit. This fruit often serves as an attractant to seed-dispersing animals. The resulting cooperative relationship presents another advantage to angiosperms in the process of dispersal. Generally endosperm formation begins after fertilization and before the first division of the zygote. Endosperm is a highly nutritive tissue that can provide food for the developing embryo, the cotyledons, and sometimes the seedling when it first appears.
Petala are usually accompanied by another set of special leaves called sepals lying just beneath the corolla.
Petals - are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. NB - both sepals and petals are modified leaves. Petala are usually accompanied by another set of special leaves called sepals lying just beneath the corolla.
Corolla - together, all of the petals/sepals of a flower are called a corolla.
Tepals - petals and sepals of a flower that look similar
Calyx (plural, calices, the sepals) and the corolla (the petals) are the outer sterile whorls of the flower, which together form what is known as the calyx.
Perianth - The term has two similar but separate meanings in botany:
In flowering plants, the perianth is composed of the outer, sterile whorls of a flower - either consist of the calyx (all sepals) and the corolla (all petals), or, if sepals and petals are not differentiated, of the perigone or tepals.
In liverworts or the Marchantiophyta** it’s the sterile tubelike tissue that surrounds the female reproductive structure or developing sporophyte.
Carpel or Gynoecium (from Ancient Greek γυνή, gyne, meaning woman, and οἶκος, oikos, meaning house) is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves, which evolved to form a closed structure containing the ovules. They did this by folding and fusing at their edges to form a chamber in which the ovules develop. In many flowers, several to many carpels are fused into a structure that resembles a single carpel. The term gynoecium is useful because it refers to the ovule producing structure in a flower, whether it is a single carpel, multiple un-fused carpels or multiple fused carpels.
In a typical flower, the gynoecium is the innermost whorl of structures and is surrounded by the androecium (stamens) and then by the perianth (all the petals and sepals). In imperfect or incomplete flowers the androecium and perianth, respectively, may be absent.
The gynoecium is often referred to as female because it gives rise to female (egg-producing) gametophytes, however, strictly speaking sporophytes do not have sex, only gametophytes do. Flowers that bear a gynoecium but no androecium are called carpellate. Flowers lacking a gynoecium are called staminate. A gynoecium may consist of a single carpel, multiple distinct (un-fused) carpels or multiple connate (fused) carpels. Each carpel typically contains one or more ovules. During pollination, pollen is deposited on the gynoecium (typically on a stigma). Successful germination of pollen and growth of pollen tubes results in fertilization of ova. There is typically one ovum in each ovule. After fertilization, ovules develop into seeds, and the gynoecium forms the pericarp of the associated fruit.
Notes -
Undifferentiated tepals are thought to be the ancestral condition in flowering plants. Amborella, which is thought to have separated earliest in the evolution of flowering plants, has flowers with undifferentiated tepals.
Distinct petals and sepals would therefore have arisen by differentiation, probably in response to animal pollination. In typical modern flowers, the outer or enclosing whorl of organs forms sepals, specialised for protection of the flower bud as it develops, while the inner whorl forms petals, which attract pollinators. In some plants the flowers have no petals, and all the tepals are sepals modified to look like petals. These organs are described as petaloid, e.g. the sepals of Hellebore.
Undifferentiated tepals are common in Monocotyledons. In tulips, for example, the first and second whorls both contain structures that look like petals. These are fused at the base to form one large, showy, six-parted structure. In lilies the organs in the first whorl are separate from the second, but all look similar, thus all the showy parts are often called tepals.
Usage of the term 'tepal' is inconsistent - some authors refer to 'sepals and petals' where others use the word 'tepals' in the same context.
A flower is called an androecium. The androecium forms a whorl surrounding the gynoecium (carpels) and inside the perianth (the petals and sepals together) if there is one. Stamens can be free or fused in various ways. A column formed from the fusion of multiple filaments is known as an androphore. Stamens have become modified through time which prevents self-fertilization, producing further diversification, allowing angiosperms eventually to fill more niches. The closed carpel of angiosperms also allows adaptations to specialized pollination syndromes and controls. This helps to prevent self-fertilization, thereby maintaining increased diversity. Once the ovary is fertilized, the carpel and some surrounding tissues develop into a fruit. This fruit often serves as an attractant to seed-dispersing animals. The resulting cooperative relationship presents another advantage to angiosperms in the process of dispersal. Generally endosperm formation begins after fertilization and before the first division of the zygote. Endosperm is a highly nutritive tissue that can provide food for the developing embryo, the cotyledons, and sometimes the seedling when it first appears.
Petala are usually accompanied by another set of special leaves called sepals lying just beneath the corolla.
Petals - are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. NB - both sepals and petals are modified leaves. Petala are usually accompanied by another set of special leaves called sepals lying just beneath the corolla.
Corolla - together, all of the petals/sepals of a flower are called a corolla.
Tepals - petals and sepals of a flower that look similar
Calyx (plural, calices, the sepals) and the corolla (the petals) are the outer sterile whorls of the flower, which together form what is known as the calyx.
Perianth - The term has two similar but separate meanings in botany:
In flowering plants, the perianth is composed of the outer, sterile whorls of a flower - either consist of the calyx (all sepals) and the corolla (all petals), or, if sepals and petals are not differentiated, of the perigone or tepals.
In liverworts or the Marchantiophyta** it’s the sterile tubelike tissue that surrounds the female reproductive structure or developing sporophyte.
Carpel or Gynoecium (from Ancient Greek γυνή, gyne, meaning woman, and οἶκος, oikos, meaning house) is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves, which evolved to form a closed structure containing the ovules. They did this by folding and fusing at their edges to form a chamber in which the ovules develop. In many flowers, several to many carpels are fused into a structure that resembles a single carpel. The term gynoecium is useful because it refers to the ovule producing structure in a flower, whether it is a single carpel, multiple un-fused carpels or multiple fused carpels.
In a typical flower, the gynoecium is the innermost whorl of structures and is surrounded by the androecium (stamens) and then by the perianth (all the petals and sepals). In imperfect or incomplete flowers the androecium and perianth, respectively, may be absent.
The gynoecium is often referred to as female because it gives rise to female (egg-producing) gametophytes, however, strictly speaking sporophytes do not have sex, only gametophytes do. Flowers that bear a gynoecium but no androecium are called carpellate. Flowers lacking a gynoecium are called staminate. A gynoecium may consist of a single carpel, multiple distinct (un-fused) carpels or multiple connate (fused) carpels. Each carpel typically contains one or more ovules. During pollination, pollen is deposited on the gynoecium (typically on a stigma). Successful germination of pollen and growth of pollen tubes results in fertilization of ova. There is typically one ovum in each ovule. After fertilization, ovules develop into seeds, and the gynoecium forms the pericarp of the associated fruit.
Notes -
Undifferentiated tepals are thought to be the ancestral condition in flowering plants. Amborella, which is thought to have separated earliest in the evolution of flowering plants, has flowers with undifferentiated tepals.
Distinct petals and sepals would therefore have arisen by differentiation, probably in response to animal pollination. In typical modern flowers, the outer or enclosing whorl of organs forms sepals, specialised for protection of the flower bud as it develops, while the inner whorl forms petals, which attract pollinators. In some plants the flowers have no petals, and all the tepals are sepals modified to look like petals. These organs are described as petaloid, e.g. the sepals of Hellebore.
Undifferentiated tepals are common in Monocotyledons. In tulips, for example, the first and second whorls both contain structures that look like petals. These are fused at the base to form one large, showy, six-parted structure. In lilies the organs in the first whorl are separate from the second, but all look similar, thus all the showy parts are often called tepals.
Usage of the term 'tepal' is inconsistent - some authors refer to 'sepals and petals' where others use the word 'tepals' in the same context.
Three Christmas Gifts ...
Gold is a chemical element and a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow colour and lustre traditionally considered attractive, which it maintains without oxidising in air or water. Chemically it is one of the least reactive solid chemical elements and therefore occurs often in free elemental or native form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium. Gold resists attacks by individual acids, but it can be dissolved by the Aqua Regia, (nitric and hydrochloric acid), so named because it dissolves gold. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to confirm the presence of gold in items, giving rise to the term the acid test.Frankincense is tapped from the very scraggy
but hardy Boswellia tree by slashing the bark, which is called striping, and allowing the exuded resins to bleed out and harden. These hardened resins are called tears. There are numerous species and varieties of frankincense trees, each producing a slightly different type of resin. Differences in soil and climate create even more diversity of the resin, even within the same species. Frankincense trees are also considered unusual for their ability to grow in environments so unforgiving that they sometimes grow directly out of solid rock. The means of initial attachment to the stone is not known but is accomplished by a bulbous disk-like swelling of the trunk. This disk-like growth at the base of the tree prevents it from being torn away from the rock during the violent storms that frequent the region they grow in. This feature is slight or absent in trees grown in rocky soil or gravel. The tears from these hardy survivors are considered superior for their more fragrant aroma. The trees start producing resin when they are about 8 to 10 years old.[1] Tapping is done 2 to 3 times a year with the final taps producing the best tears due to their higher aromatic terpene, sesquiterpene and diterpene content. Myrrh is the aromatic oleoresin, (an oleoresin
is a natural blend of an essential oil and a resin) of a number of small, thorny tree species of the genus Commiphora, which grow in dry, stony soil. Myrrh resin is a natural gum. When a tree wound penetrates through the bark and into the sapwood, the tree bleeds a resin. Myrrh gum, like frankincense, is such a resin. When people harvest myrrh, they wound the trees repeatedly to bleed them of the gum. Myrrh gum is waxy, and coagulates quickly. After the harvest, the gum becomes hard and glossy. The gum is yellowish, and may be either clear or opaque. It darkens deeply as it ages, and white streaks emerge. Myrrh gum is commonly harvested from the species Commiphora myrrha, which is native to Yemen, Somalia, Eritrea and eastern Ethiopia. W. H. Auden
Some books to note
Sunny Randall novels
1. Family Honor (1999) ISBN 0-399-14566-4
2. Perish Twice (2000) ISBN 0-399-14668-7
3. Shrink Rap (2002) ISBN 0-515-13620-4
4. Melancholy Baby (2004) ISBN 0-399-15218-0
5. Blue Screen (2006) ISBN 0-425-21598-9
6. Spare Change (2007) ISBN 0-399-15425-6
Philip Marlowe novels
1. Poodle Springs (1989). A completion of Raymond Chandler's last, unfinished, novel. ISBN 0-425-12343-X
2. Perchance to Dream (1991). A sequel to Chandler's novel The Big Sleep. ISBN 0-425-13131-9
Virgil Cole and Everett Hitch Westerns
1. Appaloosa (2005) ISBN 0-425-20432-4
2. Resolution (2008) ISBN 0-399-15504-X
3. Brimstone (2009) ISBN 0399155716
Other fiction
• Wilderness (1979) ISBN 0-440-19328-1
• Love and Glory (1980) ISBN 0-440-14629-1
• Surrogate (1991) A short story published in the crime magazine New Crimes 3 ISBN 0-8818-4737-2
• All Our Yesterdays (1994) ISBN 0-440-22146-3
• Gunman's Rhapsody (2001) ISBN 0-425-18289-4
• Double Play (2004) ISBN 0-399-15188-5
• Edenville Owls (2007) ISBN 0-399-24656-8
• The Boxer and the Spy (2008) ISBN 0-399-24775-0
Non-fiction
• Sports Illustrated Training with Weights (with John R. Marsh) (1974) ISBN 1-568-00032-4
• Three Weeks in Spring (with Joan H. Parker) (1982) ISBN 0-395-26282-8
• A Year At The Races (with Joan H. Parker) (1990) ISBN 0-670-82678-2
• Spenser's Boston (with Kasho Kumagai) (1994) ISBN 1883402506 ISBN 978-1883402501
Spenser novels
Also see Spenser (character)
1. The Godwulf Manuscript (1973) ISBN 0-440-12961-3
2. God Save the Child (1974) ISBN 0-425-04301-0
3. Mortal Stakes (1975) ISBN 0-440-15758-7
4. Promised Land (1976) (Edgar Award, 1977, Best Novel) ISBN 0-395-24771-3
5. The Judas Goat (1978) ISBN 0-440-14196-6
6. Looking for Rachel Wallace (1980) ISBN 0-440-15316-6
7. Early Autumn (1980) ISBN 0-440-12214-7
8. A Savage Place (1981) ISBN 0-440-08094-0
9. Ceremony (1982) ISBN 0-440-10993-0
10. The Widening Gyre (1983) ISBN 0-440-19535-7
11. Valediction (1984) ISBN 0-440-19246-3
12. A Catskill Eagle (1985) ISBN 0-440-11132-3
13. Taming a Sea Horse (1986) ISBN 0-440-18841-5
14. Pale Kings and Princes (1987) ISBN 0-440-20004-0
15. Crimson Joy (1988) ISBN 0-440-20343-0
16. Playmates (1989) ISBN 0-425-12001-5
17. Stardust (1990) ISBN 0-425-12723-0
18. Pastime (1991) ISBN 0-425-13293-5
19. Double Deuce (1992) ISBN 0-425-13793-7
20. Paper Doll (1993) ISBN 0-425-14155-1
21. Walking Shadow (1994) ISBN 0-425-14774-6
22. Thin Air (1995) ISBN 0-425-15290-1
23. Chance (1996) ISBN 0-425-15747-4
24. Small Vices (1997) ISBN 0-425-16248-6
25. Sudden Mischief (1998) ISBN 0-425-16828-X
26. Hush Money (1999) ISBN 0-425-17401-8
27. Hugger Mugger (2000) ISBN 0-399-14587-7
28. Potshot (2001) ISBN 0-425-18288-6
29. Widow's Walk (2002) ISBN 0-425-18904-X
30. Back Story (2003) ISBN 0-425-19479-5
31. Bad Business (2004) ISBN 0-399-15145-1
32. Cold Service (2005) ISBN 0-399-15240-7
33. School Days (2005) ISBN 0-399-15323-3
34. Hundred-Dollar Baby (2006) ISBN 0-399-15376-4
35. Now and Then (2007) ISBN 0-399-15441-8
36. Rough Weather (2008) ISBN 0-399-15519-8
37. Chasing the Bear: A Young Spenser Novel (2009) ISBN 0-399-24776-9
38. The Professional (2009) ISBN 0-399-15594-5
Also see Jesse Stone novels
1. Night Passage (1997) ISBN 0-425-18396-3
2. Trouble in Paradise (1998) ISBN 0-515-12649-7
3. Death In Paradise (2001) ISBN 0-399-14779-9
4. Stone Cold: A Jesse Stone Novel (2003) ISBN 0-425-19874-X
5. Sea Change (2006) ISBN 0-399-15267-9
6. High Profile (2007) ISBN 0-425-20609-2
7. Stranger In Paradise (2008) ISBN 0-399-15460-4
8. Night and Day (2009) ISBN 0-399-15541-4
9. Split Image (2009) ISBN 0-399-15623-6
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