The splitting of water is a chemical reaction where water is separated into oxygen and hydrogen. In photosynthesis, the water splitting gives electrons to power the electron transport chain in photosystem.
Leaves and Leaf Structure
Plants are the only organisms that have leaves. A leaf may be viewed as a solar collector crammed full of photosynthetic cells.
The raw materials of photosynthesis are water and carbon dioxide, they enter the cells of the leaf.
The products of photosynthesis are sugar and oxygen.
Water enters the root and transports up to the leaves through specialized plant cells known as xylem. Land plants must be careful not to dry out (desiccation) and have evolve structures, such as stomata, to allow gas to enter and leave the leaf. Carbon dioxide can't pass through the waxy layer covering the leaf (cuticle), but it can enter the leaf through an opening, called the stoma. Oxygen produced during photosynthesis can pass out of the leaf through the opened stomata. While these gases are moving between the inside and outside of the leaf, most of the water is lost. Carbon dioxide enters single-celled and aquatic autotrophs through no specialized structures.
Water is transparent, allows light to filter into the oceans and allows for aquatic plants to absorb light and perform photosynthesis.
Water binds to itself, due to the polarity of the water molecule.
The positive, hydrogen side of the molecule binds to the negative, called a hydrogen bond. Water binds to other things around it. This property allows for transport of water against gravity in plants. The water clings to the xylem of the plan on the sides while clinging to itself allowing it to climb up the stem of the plant.
Water is a very versatile solvent. All the reactions in cells must take place in aqueous solution.
Water's polarity also inhibits movement of its molecules. Since all the molecules are connected, they can't move freely about as other, non-polar molecules do.
Heat, the kinetic energy of molecules, is thus restricted and so water has a high specific heat (it must absorb large amounts of energy in order to change states). This means that water can serve as a temperature insulator, and does so in organisms of all kinds.
