The salt content of the water can be measured very precisely using the conductivity method. Salinity can also be measured with a hand held refractometer. A refractometer measures the change of direction or bending of the light as it passes from air to water. Light moves slower in water than air. The more salt in the water, the slower the light moves. You can see the effect of light bending (refracting) as it passes from the water into the air by placing a pencil in a glass of water. The pencil appears to bend where it enters the water.
Red blood cells and haemoglobin. Oxygen is one of the substances transported with the assistance of red blood cells. The red blood cells contain a pigment called haemoglobin, each molecule of which binds four oxygen molecules.Oxyhaemoglobin forms.he curve shows that: 1  at relatively low oxygen concentrations there is uncombined haemoglobin in the blood and little or no oxyhaemoglobin, e.g. in body tissue. 2  at relatively high oxygen concentrations there is little or no uncombined haemoglobin in the blood; it is in the form of oxyhaemoglobin, e.g. in the lungs.
Answer by TargetDriver. Confidence votes 19.7K. Among a lengthy list of molecules in red blood cells, the molecule that gives them the red color, transports oxygen and is peculiar to the red blood cell is hemoglobin.ed blood is red because the color of oxyhemoglobin is red because there is iron in oxyhemoglobin, causing that blood red color. Red blood cells are red because the iron in the heme group of the four hemoglobin proteins react with oxygen (think what color rust is) to produce a red color.