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I found this photo on a Flickr gallery and I have no idea what this plant is. Is it supposedly a type of berry or something?
Without knowing the geography of where the photo was taken, we could guess this is a European Mountain Ash (Sorbus aucuparia) which is fairly widespread in North America and Europe (but doesn't really grow in South America, Asia, Africa, Australia)…
You can look up this plant for information on the berries. They contain vitamin C, but don't have much other desirable properties.
Plants That Resemble Blueberries
Blueberries (Vaccinium spp.), one of the tastiest summertime treats in gardens or in fields, grow blue to dark blue berries. Different species thrive in the wild, and a multitude of hybrids and cultivars are available to grow in the garden. Blueberry bushes have oval, smooth-edged leaves with pointed tips. Other plants that closely resemble blueberries are relatives of blueberries and also in the heath family, such as huckleberry (Gaylussacia spp.), salal (Gaultheria shallon) and bilberry (Vaccinium myrtillus). Some unrelated plants may have similar round, purplish to black berries that may not be safe to eat. Don't eat fruit from a plant unless you're certain of its identity.
- Blueberries (Vaccinium spp.
- ), Other plants that closely resemble blueberries are relatives of blueberries and also in the heath family, such as huckleberry (Gaylussacia spp.
The Chain of Being hierarchy has God at the top, above angels, which like him are entirely spirit, without material bodies, and hence unchangeable. Beneath them are humans, consisting both of spirit and matter they can change and die, and are thus essentially impermanent. Lower still are animals and plants. At the bottom are the mineral materials of the earth itself they consist only of matter. Thus, the higher the being is in the chain, the more attributes it has, including all the attributes of the beings below it. The minerals are, in the medieval mind, a possible exception to the immutability of the material beings in the chain, as alchemy promised to turn lower elements like lead into those higher up the chain, like silver or gold.  
Each link in the chain might be divided further into its component parts. In medieval secular society, for example, the king is at the top, succeeded by the aristocracy and the clergy, and then the peasants below them. Solidifying the king's position at the top of humanity's social order is the doctrine of the divine right of kings. The implied permanent state of inequality became a source of popular grievance, and led eventually to political change as in the French Revolution.  The hierarchy was visible in every structure of society: "In the family, the father is head of the household below him, his wife below her, their children." 
Milton's Paradise Lost ranked the angels (c.f. Pseudo-Dionysius the Areopagite's ranking of angels), and Christian culture conceives of angels "in orders of archangels, seraphim, and cherubim, among others." 
The animal division is similarly subdivided, from strong, wild, and untameable lions at the top, to useful but still spirited domestic animals like dogs and horses, to merely docile farm stock like sheep. In the same way, birds could be ranked from lordly eagles high above common birds like pigeons. Below them were fish, those with bones being above the various soft sea creatures. Lower still were insects, with useful ones like bees high above nuisances like flies and beetles. The snake found itself at the bottom of the animal scale, cast down, the medieval supposed, for its wicked role in the Garden of Eden." 
Below animals came plants, ranging from the useful and strong oak at the top to the supposedly demonic yew tree at the bottom. Crop plants too were ranked from highest to lowest. 
The minerals too were graded, from useful metals (from gold down to lead), to rocks (again, from useful marble downwards), all the way down to soil. 
The chain of being links God, angels, humans, animals, plants, and minerals.  The links of the chain are:
God has created all other beings and is therefore outside creation, time, and space. He has all the spiritual attributes found in humans and angels, and uniquely has his own attributes of omnipotence, omniscience, and omnipresence. He is the model of perfection for all lower beings. 
Angelic beings Edit
In Christian angelology, angels are immortal beings of pure spirit without physical bodies, so they require temporary bodies made of earthly materials to be able to do anything in the material world.   They were thought to have spiritual attributes such as reason, love, and imagination.   Based on mentions of types of angel in the Bible, Pseudo-Dionysios devised a hierarchy of angelic beings, which other theologians like St. Thomas Aquinas adopted:  
Humans uniquely shared spiritual attributes with God and the angels above them, love and language, and physical attributes with the animals below them, like having material bodies that experienced emotions and sensations like lust and pain, and physical needs such as hunger and thirst. 
Animals have senses, are able to move, and have physical appetites. The highest animals like the lion, the king of beasts, could move vigorously, and had powerful senses such as excellent eyesight and the ability to smell their prey, while lower animals might wriggle or crawl, and the lowest like oysters were sessile, attached to the sea-bed. All, however, had the senses of touch and taste. 
Plants lacked sense organs and the ability to move, but they could grow and reproduce. The highest plants had attractive attributes like leaves and flowers, while the lowest plants, like mushrooms and moss, did not, and stayed low on the ground, close to the mineral earth. All the same, many plants had useful properties serving for food or medicine. 
At the bottom of the chain, minerals were unable to move, sense, grow, or reproduce. Their attributes were being solid and strong, while the gemstones possessed magic. The king of gems was the diamond. 
From Aristotle to Linnaeus Edit
The basic idea of a ranking of the world's organisms goes back to Aristotle's biology. In his History of Animals, where he ranked animals over plants based on their ability to move and sense, and graded the animals by their reproductive mode, live birth being "higher" than laying cold eggs, and possession of blood, warm-blooded mammals and birds again being "higher" than "bloodless" invertebrates. 
Aristotle's non-religious concept of higher and lower organisms was taken up by natural philosophers during the Scholastic period to form the basis of the Scala Naturae. The scala allowed for an ordering of beings, thus forming a basis for classification where each kind of mineral, plant and animal could be slotted into place. In medieval times, the great chain was seen as a God-given and unchangeable ordering. In the Northern Renaissance, the scientific focus shifted to biology the threefold division of the chain below humans formed the basis for Carl Linnaeus's Systema Naturæ from 1737, where he divided the physical components of the world into the three familiar kingdoms of minerals, plants and animals. 
In alchemy Edit
Alchemy used the great chain as the basis for its cosmology. Since all beings were linked into a chain, so that there was a fundamental unity of all matter, transformation from one place in the chain to the next might, according to alchemical reasoning, be possible. In turn, the unit of matter enabled alchemy to make another key assumption, the philosopher's stone, which somehow gathered and concentrated the universal spirit found in all matter along the chain, and which ex hypothesi might enable the alchemical transformation of one substance to another, such as the base metal lead to the noble metal gold. 
Scala naturae in evolution Edit
The set nature of species, and thus the absoluteness of creatures' places in the great chain, came into question during the 18th century. The dual nature of the chain, divided yet united, had always allowed for seeing creation as essentially one continuous whole, with the potential for overlap between the links.  Radical thinkers like Jean-Baptiste Lamarck saw a progression of life forms from the simplest creatures striving towards complexity and perfection, a schema accepted by zoologists like Henri de Blainville.  The very idea of an ordering of organisms, even if supposedly fixed, laid the basis for the idea of transmutation of species, whether progressive goal-directed orthogenesis or Charles Darwin's undirected theory of evolution.  
The Chain of Being continued to be part of metaphysics in 19th century education, and the concept was well known. The geologist Charles Lyell used it as a metaphor in his 1851 Elements of Geology description of the geological column, where he used the term "missing links" in relation to missing parts of the continuum. The term "missing link" later came to signify transitional fossils, particularly those bridging the gulf between man and beasts. 
The idea of the great chain as well as the derived "missing link" was abandoned in early 20th century science,  as the notion of modern animals representing ancestors of other modern animals was abandoned in biology.  The idea of a certain sequence from "lower" to "higher" however lingers on, as does the idea of progress in biology. 
Allenby and Garreau propose that the Catholic Church's narrative of the Great Chain of Being kept the peace in Europe for centuries. [ citation needed ] The very concept of rebellion simply lay outside the reality within which most people lived for to defy the King was to defy God. King James I himself wrote, "The state of monarchy is the most supreme thing upon earth: for kings are not only God's Lieutenants upon earth, and sit upon God's throne, but even by God himself they are called Gods." 
The Enlightenment broke this supposed divine plan, and fought the last vestiges of feudal hierarchy, by creating secular governmental structures that vested power into the hands of ordinary citizens, rather than in those of divinely ordained monarchs. 
However, scholars such as Brian Tierney  and Michael Novak  have noted the medieval contribution to democracy and human rights.
The American philosopher Ken Wilber described a "Great Nest of Being" which he claims to belong to a culture-independent "perennial philosophy" traceable across 3000 years of mystical and esoteric writings. Wilber's system corresponds with other concepts of transpersonal psychology.  In his 1977 book A Guide for the Perplexed, the economist E. F. Schumacher described a hierarchy of beings, with humans at the top able mindfully to perceive the "eternal now". 
A Herbaceous Conifer From the Triassic
It is hard to make broad generalizations about groups of related organisms. There are always exceptions to any rule. Still, there are some “facts” we can throw around that seem to apply pretty well to specific branches on the tree of life. For instance, all of the gymnosperm lineages we share our planet with today are woody, relatively slow to reach sexual maturity, and are generally long-lived. This has not always been the case. Fossil discoveries from France suggest that in the past, gymnosperms were experimenting with a more herbaceous lifestyle.
The fossils in question were discovered in eastern France back in the 1800’s. The strata from which they were excavated dates back to the Middle Triassic, some 247 million years ago. Immortalized in these rocks were numerous spindly plants with strap-like leaves and a few branches, each ending in what look like tiny cones. Early interpretations suggested that these may represent an extinct lycopod, however, further investigation suggested something very surprising - a conifer with an herbaceous growth habit.
Indeed, thanks to even more scrutiny, it is now largely agreed upon that what was preserved in these rocks were essentially herbaceous conifers. The fossils were given the name Aethophyllum stipulare. They are wonderfully complete, depicting roots, shoots, leaves, and reproductive organs. Moreover, the way in which they were fossilized preserved lots of fine-scale anatomical details. Taken together, there are plenty of clues available that allow paleobotanists to say a lot about how this odd conifer made a living.
For starters, they were not very big plants. Not a single specimen has been found that exceeds 2 meters (6.5 ft) in height. The main stem of these conifers only seem to branch a couple of times. Cones were formed at the tips of the upper branches and not a single specimen has been found that depicts subsequent growth following cone formation. This suggests that Aethophyllum exhibited determinate growth, meaning that individuals grew to a certain size, reproduced, and did not continue to grow after that. Female cones were situated at the tips of the upper most branches and male cones were situated at the tips of lower shoots. The smallest reproductive individuals that have been unearthed are only 30 cm (11 in) in height, which suggests that Aethophyllum was capable of reproducing within a few months of germination.
Artists reconstruction of Aethophyllum stipulare
Amazingly, researchers were also able to extract fossilized pollen and seeds from some of the Aethophyllum cones. The pollen itself is saccate, much like what we see in many extant conifers. By comparing the morphology of the pollen extracted from the cones to other fossil pollen records, researchers now feel confident that Aethophyllum is the source of pollen grains discovered in sediments from western, central, and southern Europe, Russia, Northern Africa, and China, suggesting that Aethophyllum was pretty wide spread during the Middle Triassic. Aethophyllum seeds were small, ellipsoid, and were not winged, likely germinating a short distance from the parent.
The stems of Aethophyllum are interesting in the own right. Thanks to their preservation, cross sections have been made and they reveal that these plants only ever produced secondary tracheids and primary xylem. The only place on the plant where any signs of woody secondary xylem occur are at the base of the cones. This adds further confirmation that Aethophyllum was herbaceous at the onset of sexual maturity.
Another intriguing aspect of the stem is the presence of numerous large air spaces within the stem pith. Today, this anatomical feature is present in plants like bamboo, Equisetum, and the flowering stalks of Agave, all of which exhibit alarmingly fast growth rates for plants. This suggests that not only did Aethophyllum reproduce early in its life, it also likely grew extremely fast.
1. Smallest fertile plant in the Grauvogel and Gall collections, with two stems extending from the root, and terminal ovulate cone (OC) on one branch (scale bar=10 cm). 2. Cross-section of stem in the Grauvogel and Gall collections showing cauline bundles with scanty wood (at left, top and right) surrounding large pith with large, aerenchymatous lacunae and interspersed pith parenchyma cells. Vascular cambium, phloem, and more peripheral tissues are not preserved (scale bar=200 μm). 3.Seedling in the Grauvogel and Gall collections showing primary root (R), cotyledons (C) and stem (S) with apically borne leaves (scale bar=10 cm). Quoted from SOURCE
Mature Aethophyllum aren’t the only fossils available either. Many seedlings have been discovered in close proximity to the adults. Seedlings were also exquisitely preserved, depicting hypocotyl, a primary root system, two two-veined cotyledons, and a short stem with four-veined leaves arranged in a helix. The fact that seedlings and adults were found in such close proximity lends to the idea that Aethophyllum populations were made up of multi-aged stands, not unlike some of the early successional plants we find in disturbed habitats today.
The sediments in which these plants were fossilized can also tell us something about the habitats in which Aethophyllum grew. The rock layers are made up of a mix of sediments typical of what one would find in a flood plain or delta. Also, Aethophyllum aren’t the only plant remains discovered. Many species known to grow in regularly disturbed, flood-prone habitats have also been found. Taken together these lines of evidence suggest that Aethophyllum was similar to what we would expect from herbaceous plants growing in similar habitats today. They grew fast, reproduced early, and had to jam as many generations in before the next flood ripped through and hit the reset button.
Aethophyllums small size, lack of wood, and rapid growth rate all point to a ruderal lifestyle. Today, this niche is largely filled by angiosperms. No conifers alive today can claim such territories. The discovery of Aethophyllum demonstrates that this was not always the case. The fact that pollen has been found far outside of France suggests that this ruderal lifestyle worked quite well for Aethophyllum.
The terrestrial habitats of the Middle Triassic were dominated by the distant relatives of modern day ferns, lycophytes, and gymnosperms. Needless to say, it was a very different world than anything that we are familiar with today. However, that does not mean that the pressures of natural selection were necessarily different. Aethophyllum is evidence that specific selection pressures, in this case regular flood disturbance, select for similar traits in plants through time. Why Aethophyllum went extinct is anyone’s guess. Despite how well they have been preserved, there is still a lot of mystery surrounding this plant.
Why are Lichens Important?
Lichens are important for several reasons. One of the most obvious is that they are beautiful to look at. How enchanting would the Pacific Northwest be without the long drapes of Alectoria sarmentosa (witch’s hair) hanging from the branches of the old Douglas firs and Sitka spruce? How colorful would the rocks and cliffs be in the Rocky Mountains without the reds, yellows, and greens of the crust lichens? Without these living creatures hanging off of trees or clinging to rocks, our natural areas would look pretty boring and a little more lifeless.
Alectoria sarmentosa. Photo by Karen Dillman.
Lichen-covered boulders. Photo by Doug Ladd.
Another important function of lichens is that they provide a mode of survival in harsh environments where algae cannot normally survive. Since the fungus can protect its algae, these normally water-requiring organisms can live in dry, sunny climates without dying, as long as there are occasional rain showers or flooding to let them recharge and store food for the next drought period. Because lichens enable algae to live all over the world in many different climates, they also provide a means to convert carbon dioxide in the atmosphere through photosynthesis into oxygen, which we all need to survive.
One of the ways lichens directly benefit humans is through their ability to absorb everything in their atmosphere, especially pollutants. Lichens can provide us with valuable information about the environment around us. Any heavy metals or carbon or sulfur or other pollutants in the atmosphere are absorbed into the lichen thallus. Scientists can extract these toxins and determine the levels that are present in our atmosphere. The United States Forest Service National Lichens & Air Quality Database and Clearinghouse provides more information about lichen biomonitoring and how it is helping federal land managers meet federal and agency responsibilities to detect, map, evaluate trends, and assess the ecological impacts of air pollutants.
Plants can see, hear and smell – and respond
Plants, according to Jack C Schultz, "are just very slow animals".
This is not a misunderstanding of basic biology. Schultz is a professor in the Division of Plant Sciences at the University of Missouri in Columbia, and has spent four decades investigating the interactions between plants and insects. He knows his stuff.
Instead, he is making a point about common perceptions of our leafy cousins, which he feels are too often dismissed as part of the furniture. Plants fight for territory, seek out food, evade predators and trap prey. They are as alive as any animal, and &ndash like animals &ndash they exhibit behaviour.
"To see this, you just need to make a fast movie of a growing plant &ndash then it will behave like an animal," enthuses Olivier Hamant, a plant scientist at the University of Lyon, France. Indeed, a time-lapse camera reveals the alien world of plant behaviour in all its glory, as anyone who has seen the famous woodland sequence from David Attenborough's Life series can attest.
These plants are moving with purpose, which means they must be aware of what is going on around them. "To respond correctly, plants also need sophisticated sensing devices tuned to varying conditions," says Schultz.
So what is plant sense? Well, if you believe Daniel Chamovitz of Tel Aviv University in Israel, it is not quite so different from our own as you might expect.
When Chamovitz set out to write his 2012 book What a Plant Knows &ndash in which he explores how plants experience the world by way of the most rigorous and up-to-date scientific research &ndash he did so with some trepidation.
"I was incredibly wary about what the response would be," he says.
A Beethoven symphony is of little consequence to a plant, but the approach of a hungry caterpillar is another story
His worry was not unfounded. The descriptions in his book of plants seeing, smelling, feeling and, indeed, knowing have echoes of The Secret Life of Plants, a popular book published in 1973 that appealed to a generation raised on flower power, but contained little in the way of facts.
The earlier book's most enduring claim, perhaps, is the thoroughly discredited idea that plants respond positively to the sound of classical music.
But the study of plant perception has come a long way since the 1970s, and in recent years there has been an uptick of research into plant senses. The motivation for this work has not been simply to demonstrate that "plants have feelings too", but instead to question why, and indeed how, a plant senses its surroundings.
Enter Heidi Appel and Rex Cocroft, colleagues of Schultz at Missouri who are searching for the truth about plant hearing.
"The main contribution of our work has been to provide a reason for why plants are affected by sound," says Appel. A Beethoven symphony is of little consequence to a plant, but the approach of a hungry caterpillar is another story.
In their experiments, Appel and Cocroft found that recordings of the munching noises produced by caterpillars caused plants to flood their leaves with chemical defences designed to ward off attackers. "We showed that plants responded to an ecologically-relevant 'sound' with an ecologically-relevant response," says Cocroft.
We have noses and ears, but what does a plant have?
Ecological relevance is key. Consuelo De Moraes of the Swiss Federal Institute of Technology in Zurich, along with collaborators, has shown that as well as being able to hear approaching insects, some plants can either smell them, or else smell volatile signals released by neighbouring plants in response to them.
More ominously, back in 2006 she demonstrated how a parasitic plant known as the dodder vine sniffs out a potential host. The dodder vine then wriggles through the air, before coiling itself around the luckless host and extracting its nutrients.
Conceptually, there is nothing much distinguishing these plants from us. They smell or hear something and then act accordingly, just as we do.
But, of course, there is an important difference. "We don't really know how similar the mechanisms of odour perception in plants and animals are, because we don't know much about those mechanisms in plants," says De Moraes.
We have noses and ears, but what does a plant have?
The lack of obvious centres of sensory input makes it harder to understand plant senses. It is not always the case &ndash the photoreceptors that plants use to "see", for example, are fairly well-studied &ndash but it is certainly an area that merits further investigation.
For their part, Appel and Cocroft are hoping to track down the part or parts of a plant that respond to sound.
Researchers have begun to find repeating patterns that hint at deep parallels with animals
Likely candidates are mechanoreceptor proteins found in all plant cells. These convert micro-deformations of the kind that sound waves can generate as they wash over an object into electrical or chemical signals.
They are testing to see whether plants with defective mechanoreceptors can still respond to insect noise. For a plant, it seems, there may be no need for something as cumbersome as an ear.
Another ability we share with plants is proprioception: the "sixth sense" that enables (some of) us to touch type, juggle, and generally know where various bits of our body are in space.
Because this is a sense that is not intrinsically tied with one organ in animals, but rather relies on a feedback loop between mechanoreceptors in muscles and the brain, the comparison with plants is neater. While the molecular details are a little different, plants also have mechanoreceptors that detect changes in their surroundings and respond accordingly.
"The overarching idea is the same," says Hamant, who co-authored a 2016 review of proprioception research. "So far, what we know is that in plants it is more to do with microtubules [structural components of the cell], responding to stretch and mechanical deformation."
In fact, a study published in 2015 appears to show similarities that go even deeper, suggesting a role for actin &ndash a key component in muscle tissue &ndash in plant proprioception. "This is less supported," says Hamant, "but there has been some evidence that actin fibres in tissue are involved almost like muscle."
These findings are not unique. As research into plant senses has progressed, researchers have begun to find repeating patterns that hint at deep parallels with animals.
Today there are plant researchers investigating such traditionally non-plant areas as memory, learning and problem-solving
In 2014, a team at the University of Lausanne in Switzerland showed that when a caterpillar attacks an Arabidopsis plant, it triggers a wave of electrical activity. The presence of electrical signalling in plants is not a new idea &ndash physiologist John Burdon-Sanderson proposed it as a mechanism for the action of the Venus flytrap as early as 1874 &ndash but what is surprising is the role played by molecules called glutamate receptors.
Glutamate is the most important neurotransmitter in our central nervous system, and it plays exactly the same role in plants, except with one crucial difference: plants do not have nervous systems.
"Molecular biology and genomics tell us that plants and animals are composed of a surprisingly limited set of molecular 'building blocks' that are very much alike," says Fatima Cvrčková, a researcher at Charles University in Prague, Czech Republic. Electrical communication has evolved in two distinct ways, each time employing a set of building blocks that presumably pre-dates the split between animals and plants around 1.5 billion years ago.
"Evolution has led to a certain number of potential mechanisms for communication, and while you can get to that in different ways, the end point is still the same," says Chamovitz.
The realisation that such similarities exist, and that plants have a far greater ability to sense their world than appearances might suggest, has led to some remarkable claims about "plant intelligence", and even spawned a new discipline. Electrical signalling in plants was one of the key factors in the birth of "plant neurobiology" (a term used despite the lack of neurons in plants), and today there are plant researchers investigating such traditionally non-plant areas as memory, learning and problem-solving.
Despite lacking eyes, plants such as Arabidopsis possess at least 11 types of photoreceptor, compared to our measly four
This way of thinking has even led to law makers in Switzerland setting guidelines designed to protect "the dignity of plants" &ndash whatever that means.
And while many consider terms like "plant intelligence" and "plant neurobiology" to be metaphorical, they have still been met with a lot of criticism, not least from Chamovitz. "Do I think plants are smart? I think plants are complex," he says. Complexity, he says, should not be confused with intelligence.
So while it is useful to describe plants in anthropomorphic terms to communicate ideas, there are limits. The danger is that we end up viewing plants as inferior versions of animals, which completely misses the point.
"We plant scientists are happy to talk about similarities and differences between the plant and animal lifestyles when presenting results of plant research to the general public," says Cvrčková. However, she thinks reliance on animal-based metaphors to describe plants comes with issues.
"You want to avoid [such metaphors], unless you are interested in a (usually futile) debate about a carrot's ability to feel pain when you bite into it."
Plants are supremely adapted for doing exactly what they need to do. They may lack a nervous system, a brain and other features we associate with complexity, but they excel in other areas.
We are more plant-like than we would like to think
For example, despite lacking eyes, plants such as Arabidopsis possess at least 11 types of photoreceptor, compared to our measly four. This means that, in a way, their vision is more complex than ours. Plants have different priorities, and their sensory systems reflect this. As Chamovitz points out in his book: "light for a plant is much more than a signal light is food."
So while plants face many of the same challenges as animals, their sensory requirements are equally shaped by the things that distinguish them. "The rootedness of plants &ndash the fact that they are unmoving &ndash means they actually have to be much more aware of their environment than you or I do," says Chamovitz.
To full appreciate how plants perceive the world, it is important that scientists and the wider public appreciate them for what they are.
"The danger for the plant people is that if we keep comparing [plants] with animals we might miss the value of plants," says Hamant.
"I would like to see plants acknowledged more as the amazing, interesting, exotic living beings they are," agrees Cvrčková, "and less as a mere source of human nutrition and biofuels." Such an attitude will benefit everyone. Genetics, electrophysiology and the discovery of transposons are just a few examples of fields that began with research in plants, and they have all proved revolutionary for biology as a whole.
Conversely, the realisation that we have some things in common with plants might be an opportunity to accept that we are more plant-like than we would like to think, just as plants are more animal-like than we usually assume.
"Maybe we are more mechanistic than we think we are," concludes Chamovitz. For him, the similarities should alert us to plants' surprising complexity, and to the common factors that connect all life on Earth.
"Then we can start to appreciate the unity in biology."
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Pest Control Agents from Natural Products
The extremely poisonous alkaloid strychnine ( Figure 3.14 ) was isolated in pure form by Pelletier and Caventou in 1818 from St. Ignatius beans, Strychnos ignatii ( Loganiaceae ), a woody vine native to the Philippines. It is now obtained from the ripe and dried seeds of S. nux vomica, a related plant growing in India, Sri Lanka, and Southeast Asia. The seeds contain 1.0–1.5% strychnine and about the same amount of its 2,3-dimethoxy derivative, brucine. Philippe et al. (2004) have recently reviewed the ethnobotany, pharmacotoxicology, and chemistry of various Strychnos alkaloids.
Figure 3.14 . Structures of rodenticides.
LS1-5 to LS1-7 – Photosynthesis
Rate of Photosynthesis – this lab asks students to place elodea in a test tube and count bubbles under different conditions this lab is simpler than the AP Lab and requires a lab report.
Do Plants Consume or Release CO2 – using phenol red as an indicator, students observe changes in color in plants that are stored in the light and those stored in the dark
Photosynthesis Simulation – a virtual lab that measures plant growth and rate of photosynthesis under different colors and intensity of light
Waterweed simulator – another virtual lab that counts bubbles (oxygen) produced during photosynthesis.
Chemiosmosis Coloring – color the membrane of a chloroplast to to learn how water and electrons are shuffled to create ATP
Photosystems Labeling – practice labeling the photosystems
Photosynthesis and Respiration Model – students examine a model, focus on key details and answer an essential question about how the two processes are related
LS1-6 Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large carbon-based molecules.
- Students construct an explanation that includes: a) The relationship between the carbon, hydrogen, and oxygen atoms from sugar molecules formed in or ingested by an organism and those same atoms found in amino acids and other large carbon-based molecules
- Students identify and describe the evidence to construct the explanation, including:
a) All organisms take in matter and rearrange the atoms in chemical reactions.
b) Cellular respiration involves chemical reactions in which energy is released
c) Sugar molecules are composed of carbon, oxygen, and hydrogen atoms.
d) Amino acids and other carbon-based molecules are composed of carbon, oxygen, and hydrogen
e) Chemical reactions can create products that are more complex than the reactants.
f) Chemical reactions involve changes in the energies of the molecules involved in the reaction.
Concept Map – Organic Compounds – organizes the four main groups of organic compounds: nucleic acids, lipids, carbohydrates, and proteins details how these compounds are used by living systems
Elements found in living things – coloring shows the proportion of elements, C, H, N, P, K, O, S, and Ca
(Article) Wood Alcohol Poisonings – an article that helps students understand how a slight change in the chemical structure, ethyl to methyl can turn a substance into a poison.
LS1-7 Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy
- From a given model, students identify and describe the components of the model relevant for their illustration of cellular respiration, including: i. Matter in the form of food molecules, oxygen, and the products of their reaction (e.g., water and CO2) ii. The breaking and formation of chemical bonds and iii. Energy from the chemical reactions.
- From the given model, students describe the relationships between components, including: a)Carbon dioxide and water are produced from sugar and oxygen b) The process of cellular respiration releases energy
(Lab) Respiration – using germinating and non-germinating seeds, measure the rate of oxygen consumption using respirometers
(Case Study) Mystery of the Seven Deaths – examine a case of poisoning, shows how cyanice interferes with the functioning of the mitochondria and cellular respiration
Cellular Respiration Concept Map – map of the steps involved in cellular respiration
Cellular Respiration Virtual Lab – AP Lab that can be performed online
The Carbon Cycle – simple diagram of the carbon cycle identify how respiration and photosynthesis are related
Mile-a-minute weed Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Mile-a-minute weed (Persicaria perfoliata) is a vigorous, barbed vine that smothers other herbaceous plants, shrubs and even trees by growing over them. Growing up to six inches per day, mile-a-minute weed forms dense mats that cover other plants and then stresses and weakens them through smothering and physically damaging them. Sunlight is blocked, thus decreasing the covered plant’s ability to photosynthesize and the weight and pressure of the mile-a-minute weed can cause poor growth of branches and foliage. The smothering can eventually kill overtopped plants.
Mile-a-minute weed (Persicaria perfoliata (L.) H. Gross, formerly Polygonum perfoliatum) is a member of the polygonum or buckwheat family. It is native to India and Eastern Asia and was accidentally introduced via contaminated holly seed into York County, Pennsylvania in 1930. Mile-a-minute weed has been found in all the Mid-Atlantic states, southern New England, North Carolina, Ohio, and Oregon (2011). In New York, mile-a-minute weed has been recorded mostly in counties south of the northern Connecticut border. Mile-a-minute weed has a large potential to expand in cooler areas, as the seed requires an eight-week cold period in order to flower. It is estimated that mile-a-minute weed is in only 20% of its potential U.S. range.
Infestations of mile-a-minute weed decrease native vegetation and habitat in natural areas impacting plants and the wildlife that depend on those plants as well. Mile-a-minute weed can also be a major pest in Christmas tree plantations, reforestation areas and young forest stands, and landscape nurseries. Areas that are regularly disturbed, such as powerline and utility right-of-ways where openings are created through regular herbicide use are prime locations for mile-a-minute weed establishment. Small populations of rare plants could be completely destroyed. Thickets of these barbed plants can also be a deterrent to recreation.
Mile-a-minute weed is an herbaceous annual vine. Its leaves are alternate, light green, 4 to 7 cm long and 5 to 9 cm wide, and shaped like an equilateral triangle. Its green vines are narrow and delicate, becoming woody and reddish with time. The vines and the undersides of leaves are covered with recurved barbs that aid in its ability to climb. Mile-a-minute has ocreae that surround the stems at nodes. This distinctive 1 to 2 cm feature is cup-shaped and leafy. Flower buds, and thus flowers and fruit, grow from these ocreae. When the small, white, inconspicuous flowers are pollinated they form spikes of blue, berry-like fruits, each containing a single glossy, black seed called an achene. Vines can grow up to six inches per day.
Mile-a-minute fruiting spike, ocreae, and barbs. Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Mile-a-minute weed is primarily a self-fertile plant and does not need any pollinators to produce viable seeds. Its ability to flower and produce seeds over a long period of time (June through October) make mile-a-minute weed a prolific seeder. Seeds can be viable in the soil for up to six years and can germinate at staggered intervals. Vines are killed by frost and the seeds overwinter in the soil. Mile-a-minute seeds require an eight-week vernalization period at temperatures below 10 degrees Celsius in order to flower, and therefore be a threat. Germination is generally early April through early July.
Seeds are carried long distances by birds, which are presumed to be the main cause of long distance spread. Deer, chipmunks, squirrels and even one particular species of ant is known to eat mile-a-minute weed fruit. Viable seeds have been found in deer scat an indication that other animals may also be vectors.
Mile-a-minute weed seeds can float for seven to nine days, which allows for long distance movement in water. This movement can be amplified during storms when vines hanging over waterways drop their fruit into fast moving waters, which then spread the seeds throughout a watershed.
Mile-a-minute weed is generally found colonizing natural and man-made disturbed and open areas and along the edges of woods, streams, wetlands, uncultivated fields, and roads. It can also be found in areas with extremely wet environments with poor soil structure, and while it will grow in drier soils, mile-a-minute prefers high moisture soils. It will tolerate some shade for part of the day, but prefers full sun. Using its specially-adapted recurved barbs, mile-a-minute weed can reach sunlight by climbing over plants, helping it outcompete other vegetation.
Mile-a-minute weed infested area. USDA APHIS PPQ Archive, USDA APHIS PPQ, Bugwood.org
Mile-a-minute has a number of management options that can be employed. Different sites will dictate different levels of management depending on conditions and the level of infestation. Once all the plants have been removed, on-going monitoring and management must occur for up to six years in order to exhaust any seeds remaining in the soil.
The mile-a-minute weevil, Rhinocominus latipes Korotyaev, is a 2 mm long, black weevil which is often covered by an exuded orange film produced from the mile-a-minute plants it feeds on. This small weevil is host-specific to mile-a-minute weed and has been successfully released and recovered in multiple locations in the U.S.
Mile-a-minute Weevil, Rhinocominus latipes, adult on mile-a-minute. Note the recurved barbs. Ellen Lake, University of Delaware, Bugwood.org
The adult weevils feed on the leaves of mile-a-minute weed and females lay eggs on the leaves and stems. When the eggs hatch, the larvae bore into the stem to complete their development, feeding on the stems between the nodes. The larvae then emerge and drop to the soil to pupate. There are three to four overlapping generations per year, with about a month needed per generation. Egg laying ceases in late summer or early fall, and the mile-a-minute weevil overwinters as an adult in the soil or leaf litter.
Mile-a-minute weevil feeding damage can stunt plants by causing the loss of apical dominance and can delay seed production. In the presence of competing vegetation, mile-a-minute weed can be killed by the weevil. The mile-a-minute weevil is more effective in the sun than in the shade. Over time, mile-a-minute weevils have been shown to reduce spring seedling counts. Biological control of mile-a-minute weed is currently the most promising and cost effective method.
Feeding damage of adult mile-a-minute weevils. Ellen Lake, University of Delaware, Bugwood.org
For more information on the mile-a-minute weevil, check the University of Delaware Biological Control on Invasive Plants Research website:
Cultural methods can be used to help prevent mile-a-minute weed introduction to a new area. Maintain a stable plant community avoid creating disturbances, openings or gaps in existing vegetation and maintain wide, shade-producing, vegetative buffers along streams and wooded areas to prevent establishment.
Manual and Mechanical Control
Hand-pulling of vines can be effective ideally before the barbs harden, afterwards thicker gloves are needed. Pull and bale vines and roots as early in the season as possible. Let the piles of vines dry out completely before disposing. Later in the season, vines must be pulled with caution as the fruit could be knocked off or spread more easily. Collected plants can be incinerated or burned, left to dry and piled on site, or bagged and landfilled (least preferred). Dry piles left on site should be monitored and managed a few times each year, especially during the spring and early summer germination period to ensure any germinating seedlings are destroyed.
Low growing populations of mile-a-minute weed can have their resources exhausted through repeated mowing or cutting. This will reduce flower production and therefore reduce fruit production.
Mile-a-minute weed can be controlled with commonly used herbicides in moderate doses. The challenge with herbicides is mile-a-minute’s ability to grow over the top of desirable vegetation, and spraying the foliage of only the mile-a-minute weed can be challenging. Pre-emergent herbicides (herbicides that prevent seed germination) can be used with extensive infestations, often in combination with spot treatments of post-emergent herbicides (herbicides applied to the growing plant) for seedlings that escape control. Small populations are better controlled with post-emergent herbicides. General chemical control guidelines can be found at http://www.docs.dcnr.pa.gov/cs/groups/public/documents/document/dcnr_20033415.pdf. Areas treated with herbicides need to be monitored and retreated as necessary when new seedlings emerge from the seed bank, see above. Please contact your local Cornell Cooperative Extension office http://www.cce.cornell.edu for pesticide use guidelines. For treating wetland areas or infestations near water, contact a certified pesticide applicator. Always apply pesticides according to the label directions it’s the law.
New York Distribution Map
This map shows confirmed observations (green points) submitted to the NYS Invasive Species Database. Absence of data does not necessarily mean absence of the species at that site, but that it has not been reported there. For more information, please visit iMapInvasives.
X and Y Chromosomes
In organisms where two sexes are distinct, certain chromosomes (usually one or two) in a diploid cell differ from the rest in staining reaction and behaviour during cell division. These chromosomes determine the sex of an individual and are thus called sex chromosomes . The rest of the chromosomes are said to be autosomes. In a diploid individual, there are 2n-2 autosomes and two sex chromosomes.
What is X and Y chromosomes?
In certain insects like grasshoppers and roundworms females have two sex or X-chromosomes while males have only one, and thus females are designated XX and males XO. In humans and other mammals, most insects (e.g., Drosophila) and many plants (e.g., Coccinia, Melandrium), females have two X-chromosomes (XX), whereas males have one X and a morphologically distinct Y-chromosome (XY). Y-chromosome, though different in size and shape, pairs with X during meiosis. Thus females are XX and males are XY. Since, males produce two types of gametes, X or O in XO type and X or Y in XY type, they are said to be heterogametic Females are homogametic, producing only one type of gamete with an X-chromosome.
However, in birds and some reptiles, females are heterogametic while males are homogametic. To avoid confusion with the male heterogametic X and Y chromosomes system, this is referred to WZ system with males WW and females WZ .
X and Y chromosomes and Sex determination
Sex determination is concerned with the study of factors which are responsible for making an individual male, female or a hermaphrodite. Since long, both biologists and non- biologists are puzzled by the riddle that what determines the sex of an offspring. Numerous mistaken hypothesis and wild guesses were put forward but a valid solution became possible only with the discovery of sex chromosomes in the early years of the 20th century. Latter it has been suggested that the Sex determination is dependent on X and Y chromosomes.