Friday, February 17, 2012

Even More Poisonous Plants...

Common Snowberry





Symphoricarpos albus and related spp.

Snowberries are sometimes grown as ornamental shrubs in North America and Europe. One child, after eating three berries, experienced mild sedation, vomiting, and slight dizziness. Others have died from eating them. In several indigenous languages, they are known as ghost berries or corpse berries.

Calla Lilies



Zantedeschia aethiopica and related spp.

When ingested, this attractive flower causes intense burning of the mouth and throat. however, it is seldom fatal. They are grown as houseplants in many places, although they are native to South America.

Jack in the Pulpit



Grows in much of Eastern North America. The plant causes salivation, nausea, and vomiting. Very rarely, it causes irregular heart beat, fits, coma, and death. Fortunately, the plant burns when it is swallowed, so a fatal dose is rare.

Buttercups



Ranunculus spp. and related genera

Attractive yellow flowers. They are found throughout North America. The fresh plants can cause painful blistering of the skin and irritate the mouth. However, they taste horrible, so it is rare that they are eaten in quantity. However, a fatal dose is not impossible.

Thursday, February 16, 2012

More Poisonous Plants...

Black Hellebore

Helleborus niger and related spp.

An herbaceous perennial, with the flowers blooming in winter or spring. Poisoning is rare, but can be fatal. Symptoms of poisoning involve cramps, nausea, visual disturbances, and vomiting.

Larkspur and Delphinium



Consolida ajacis, Delphinium spp.

These plants grow in many gardens. Their poison is similar to that of aconite, a highly poisonous plant. The amount of poison in these plants depends on the age of the plant and the species, but a fatal dose is not impossible.

Hemlock



Conium maculatum

Carrot like plants. The root can be mistaken for carrots and the leaves for parsley. The plant has an unpleasant taste and smell, which is fortunate, since it is deadly poison. It was used to kill Socrates and is said to be a very humane way to die. Initially, those who eat it will feel stimulated, then fall into severe depression of the nervous system, became paralyzed, and die if not helped.

Thursday, February 9, 2012



Energy plays an important role in chemical reactions. A chemical reaction that stores energy is called an endothermic reaction. In photosynthesis, solar energy is stored in the sugar molecules. Most endothermic reactions store energy in the form of heat. Another endothermic reaction is putting a chemical ice pack on an injury. The chemicals inside are stored separately, but when mixed feel cool against the skin.




Exothermic reactions are the opposite of endothermic. These release energy. Burning something is an exothermic reaction. So is the reaction that digests your food. As food molecules are broken down, energy is released that the body uses to function.

Wednesday, February 8, 2012

Catalysts



A catalyst is something added to a chemical reaction in order to speed it up. The reactants have to reach a certain energy level before they can react, and a catalyst can speed up the process. It reduces the amount of energy needed for the reaction. For example, chlorophyll is a catalyst that speeds up photosynthesis. Enzymes are also catalysts, found in living cells. They are used in reactions that are involved in digestion, cell construction and reproduction. If we did not have enzymes, we would be unable to produce glucose at the speed our body needs it, so these are essential to life.


What do you add if you want to slow a reaction down? You use a negative catalyst. If a chemical reaction, such as food spoiling, is occurring, it can be slowed down, by things like fruit freshener. Negative catalysts, or inhibitors, help keep the reactants apart, or bond with other reactants so the reaction will not take place.

Monday, February 6, 2012

Reacting

Chemical reactions occur when two or more elements combine and form a new substance or when a substance is broken down into its seperate elements. Chemical reactions are everywhere. Bread rising is a chemical reaction. Fireworks going off is a chemical reaction. Fire burning is (well, I suppose you've already guessed this) a chemical reaction.

Reactions often change heat. An exothermic reaction, for example, is one where the product is hotter than what went into it. If the product is cooler than its reactants, then its called an enothermic reaction. There are many different sorts of chemical reactions. If an element combines with oxygen, the reaction is an oxidation reaction. If oxygen is removed from a substance, it is called a reduction reaction. If elements other than oxygen combine, then the substance formed is called a composition reaction. If a substance is broken down, it's called a decomposition reaction. Some reactions, like rust, occur very slowly. Others happen quickly, like fireworks.

In order for a reaction to take place, the reactants must all be in contact with each other. The size also matters. A cube of iron will rust more slowly than a sheet with the same amount of material, because the thin sheet has more surface area and the oxygen in the air can react with more iron particles. The concentration of the reactants also speeds up the reaction. The more molecules of each reactant, the more likely they are to come in contact and react. Heat can also increase the speed of the reaction, because it causes the heat causes the molecules to move more quickly. Adding a catalyst can also help. A catalyst speeds up the reaction, but is not used up.