*Chemical Elements and Water*

The most commonly occuring elements in all living things are hydrogen, oxygen, carbon, and nitrogen. On average, 96% of an organism is made of of these. They are called essential elements, because we absolutely need them, and a lot of them, to live.

About 4% of an organism is made up of phosphorus, sulfur, sodium, iron, and calcium (we spent a few days researching these in groups). There are also trace elements, which we do need but in very small amounts. If we don't have enough in our bodies, or if we have too much, it is harmful. Iodine and magnesium are two examples of these.

Sodium is in sodium nitrate, which gives us nitrogen (an essential element) in a form we can actually consume. Iron is part of hemoglobin, which attracts oxygen uin the body. Phosphorus is in nucleic acid, which is in DNA. Sulfur is in sulfuric acid, which is in matches. Calcium ions make skeletal muscles. Small amounts of iodine prevent goiters.
Small amounts of magnesium prevents magnesium deficiency, which can cause hyperexcitability, sleepiness, and muscle weakness.

Goiters like this happen when you don't have enough iodine.

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​A water molecule is a polar molecule, a molecule with opposite charges on opposite sides. It has a polar covalent bond as well as a hydrogen bond. A polar covalent bond is between atoms that differ in electronegativity, the shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive. A hydrogen bond is a type of a weak chemical bond formed when a slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to a slightly negative atom of a polar covalent bond in another molecule.
Amino acids have these too.

Electronegativity - The attraction of an atom for the electrons of a covalent bond.

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The thermal properties of water are that it has a boiling point of 100 degrees celsius and a freezing point of 0 degrees celsius. At 100 degrees celsius water converts from a liquid phase into a gaseous phase, water vapor, and at 0 degrees celsius water converts from a liquid phase into a solid phase, ice.
The cohesive property of water is caused by the hydrogen bonding of the molecule and its when water is attracted to other water molecules. The oxygen atom of a water molecule has a negative charge and the hydrogen atoms of a water molecule have positive charges, therefore causing the positively charged hydrogen atoms of one water molecule to be attracted to the negatively charged oxygen atom of another water molecule.
The oxygen atoms are negative because they have a higher electronegativity than hydrogen.
The solvent properties of water are caused by the polarity of water. Water can dissolve just about any substance and this is good because water is used to transfer nutrients to plants and animals. Also many chemical or biochemical reactions take place in aqueous solutions, which is also water.

The properties of water are used in living organisms as coolants, mediums for metabolic reactions, and transport mediums. Water is used as a coolant in living organisms especially when it comes to animals, such as humans. The human body is made up of over 70% of water and when the human body begins to overheat from a physical activity the body uses the water that it is composed of as sweat which is absorbed by the skin allowing one's body to cool.
Water is also used as a transport medium in living organisms, such as humans, because as a part of the body our blood cells have water inside of them and water is composed of oxygen and hydrogen, therefore oxygen is capable of being transported throughout the body from the water that is contained by our blood cells.
Water is used as a medium for metabolic reactions too. Water is used for metabolic reactions because when you eat food you need to digest your food in order to use the proteins, lipids, and carbohydrates in your body that the food provides. However, in order to complete the process of digestion you have to have water inside of your system to start, as well as complete, the process of breaking down your food.

Carbohydrates, Lipids, and Proteins


Organic and inorganic molecules are defined as such mainly as a result of their composition, and if they are living or not. Organic substances always contain carbon atoms, and the other atoms usually present are hydrogen,oxygen,nitrogen, sulfur, and phosphorus. Organic compounds have been defined by some a substances that contain carbon, but that definition is flawed. The substance also has to be living, or else things like coal, which is pure carbon, would be considered organic. Inorganic substances are not living substances, and they do not always contain the essential elements for life that were mentioned above. If they are non living, then they can be defined as inorganic, so things like metals would fall under that category Organic substances will always contain carbon, hydrogen, and oxygen.

Amino acids all have two features that are consistent with each other, the amino group on the left and the carboxylic acid group on the right, and the only difference is the center of the structure. This is the side chain, as indicated in the picture below, and is what signifies amino acids as different.


Glucose, an essential sugar needed in your body, is structured in a hexagonal pattern, indicated by the picture below. This is the most common monosaccharide, and contains tbeta-D-glucose.gifhe indicators of a sugar, a carbonyl group and many hydroxyl groups. Glucose, as you can see by the picture, contains three elements essential to the functioning of your body, carbon, hydrogen, and oxygen.

Ribose, which is the sugar component of RNA, is in a structure similar to glucose. This similarity is a result of them both being sugars, as ribose does contain the hydroxyl groups that signify a sugar. They also contain mostly the same elements, but ribose is lacking carbon in it's structure.
Fatty acids, bonded to glycerol on the right, are one of the molecules that construct a fat when bonded. The fatty acids are the structure that looks like a long chain of carbon molecules and hydrogen molecules. When fatty acids bond with glycerol, they will form a fat. Glycerol is an alcohol with three carbon atoms, and each one has a hydroxyl group branching off, indicated by the picture on the left. Triglyceride-saturated is just another term for saturated fat.For more information on structures see topic packet page 11.

Monosaccharides are basically simple sugars, as the term monosaccharide means single sugar, and the most common monosaccharide is glucose (diagrammed under 3.2.2). Other examples of monosaccharides are sugars like ribose (also diagrammed above), and another important sugar, fructose which is diagrammed below. Since all three of these are monosaccharides, they only have one structure, and are not visibly bonded to another.
Disaccharides are structures that consist of two monosaccharides when they bond together. This bonding is referred to as a glycosidic linkage, which is defined as a covalent bond that holds two monosaccharides together after they undergo a dehydration reaction. The bonds can occur between two of the same sugars, of two different ones. The most common of these disaccharides is sucrose, which is formed after fructose and glucose bond together, shown below.glucose,_fructose,_sucrose.gif

Another disaccharide, formed by the bonding of two glucose molecules, is maltose, diagrammed below. Maltose is also known as malt sugar, and is an ingredient used to brew beer. Lactose is also another disaccharide, and this is the sugar present in milk that is formed by the bonding of glucose and galactose, show on the right.lactose.jpg


Polysaccharides are macromolecules that have anywhere from hundreds to thousands of glycosidic linkages. Polysaccharides serve a variety of functions and these are determined by the sugar monomers and the positions of the glycosidic linkages. One of these functions is storage, which is seen with starch, the storage polysaccharide of plants. As you can see, it contains many molecules, indicating that it is a polysaccharide.

Cellulose is another polysaccharide, and is important in the creation of tough plant cell walls, diagrammed below.


Glycogen, a very important carbohydrate, is also a polysaccharide structured below.


Functions of Glucose, Lactose, and Glycogen in Animals.

-Is the main source of Energy in animals. Glucose is a monosaccharide meaning it’s a simple sugar. The brains and bodies of animals use glucose for energy everyday.


-Lactose is a carbohydrate found in milk. When it is digested, it is broken to glucose and galactose. Then the galactose is broken down to glucose, contributing to the amount of energy an animal has.

-Glycogen stores large amounts of glucose.

Functions of Fructose, Sucrose, and Cellulose in Plants.

-Is a quick source of energy for plants( like Glucose)

-Used as storage or as a reservoir of glucose

-The structural component in the Cell Wall (Makes up most of the cell wall)


6 Functions of lipids

1. Lipids (fats) are used as a shock absorber. Ex. Your tush

2. Lipids (fats and oils) are used as insulation.

3. Phospholipids function as the cell membrane of cells.

4. Lipids are biological foods. They actually provide twice as much energy as carbs.

5. Proteins and carbs can be converted into fats (aka lipids) which are stored in the adipose tissue.

6. Provides fuel for aerobic resperation (energy through oxygen) through a process called fatty acid oxidation which takes place in the mitochondria.

external image moz-screenshot.pngexternal image moz-screenshot-1.pngexternal image moz-screenshot-2.pngbilayer.gif Phospholipid
Glycerol Phosphorus Glycerol

The use of Lipids and Carbohydrates in Energy Storage


1. Are insoluble in water, therefore not holding up osmosis.

2. Contain 2X more energy than carbohydrates


1. Can be broken down quicker and easier, therefore releasing energy quicker.

2. Soluble in water, therefore easier to transport.