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State that the first cells originated in water.
List reasons why water is a substance on which life depends </aside>
Water on earth originated around 4.5 billion years ago, and life emerged FROM water 3.8 billion years ago
The first cells evolved in a watery environment
This is believed to have been in the deep oceans, close to hydrothermal vents in the Earth's crust
Some water and solutes got trapped within a membrane
Chemical reactions began occurring within the membrane-bound structure
This led to the evolution of cells
Water in its liquid state allows dissolved molecules to move around, so they are easily able to collide and react with each other
Most life processes occur in water
The link between water and life is so strong that scientists looking for life on other planets and moons look for evidence of water to suggest that life could have occurred there
Water became the liquid solvent with which the ingredients of life (both organic and inorganic compounds) came together to form life
Water is also a SOLVENT, meaning it has the ability to dissolve a variety of molecules
The fact that water is a solvent allows for multicellular organisms to transport other molecules around the body, and it being a solvent also allows it to be a MEDIUM in which chemical reactions of life occur (fun fact!!!: ur cytoplasm of the cell where most reactions take place is 80% water)
Water is also a METABOLITE, meaning it is a chemical involved in chemical reactions that take place in cells - This is either as a reactant (meaning a chemical is reacting with water) or is a product of a reaction (a byproduct of another reaction)
Water is also a TEMPERATURE BUFFER, meaning that it has a high specific heat capacity that allows it to act as a buffer to certain reactions that involve enzymes - Enzymes are sensitive to temperature (denature easily) and therefore the high specific heat capacity of water allows for it to buffer these reactions
A HIGH SPECIFIC HEAT CAPACITY can be defined as the ability of a substance to both absorb, or release a large amount of heat energy with only small changes in temperature as a result
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Describe the structure of an atom.
Outline the formation of ionic and covalent bonds between atoms.
Explain the sharing of electrons between atoms in a polar covalent bond.
State the location of the polar covalent bond within a water molecule.
Explain the partial charges of the oxygen and hydrogen atoms within a water molecule.
Draw a water molecule, including notation to depict the partial charges of the atoms.
Outline the cause of the formation of hydrogen bonds between water molecules.
Outline the consequences of the collective strength of hydrogen bonds between water molecules. </aside>
An atom is the smallest unit of matter that is unique to a particular element. An atom has Protons (positively charged), Neutrons (No net charge), and Electrons (negatively charged)