Chapter 2 is about Molecular level of life/ the chemical component of life. What does chemistry have to do with our life?
Chemical aspect of life.
Matter: anything in the universe that has weight and occupies space. The weight is called mass. The mass will remain constant regardless of gravity.
Can exist in our body in three different forms
Three states of matter in our body. * Solid: in our body are organs, Bones, they will have different shapes. * Liquid: In our body is water, plasma in blood, saliva, tears, embryonic fluid. These liquids are called an inorganic makeup of our body. Liquid takes form of its container. * Gases: no definite shape, carbon dioxide, oxygen, hydrogen gas, and nitrogen gas.
Elements: unique substances in our body that cannot be broken down into simpler substances by ordinary means. Four elements that compose our body. * Carbon: * Hydrogen: * Oxygen: * Nitrogen:
Make up 96% of our bodies weight.
Atoms
Defined as the smallest non destructible parts of any element that will retain the characteristic of that element.
Atoms have structures which means that structure means how a item is put together
Contain nucleus, which contains protons and neutrons
Protons: have an electrical charge and will weigh one atomic mass unit.
Neutrons: are chargless. Hence neutral. Will weigh one atomic mass unit.
Electrons: will be found moving around the nucleus. Will have a negative charge. Do not have any weight meaning they are weightless and have no atomic mass.
Read about
Isotopes, radioisotopes
Molecules/compound
Molecules are formed when there is a combination of two or more atoms.
If two or more atoms of the same element combine it is called a molecule of that element.
Example: one hydrogen plus another hydrogen is a molecule of hydrogen. or if two or more atoms of different elements combine then the result will be called the molecule of a compound. An example would be