Chemical Basis of Life
Chemical Basis of Life
Chemistry
Atoms – smallest particle of an element
Subatomic particles: * Protons * Neutrons * Electrons
Molecules – a unit formed by 2 or more atoms joined together
Elements
Compounds
Mass
Weight
Inorganic Compounds – molecules that do not necessarily contain a carbon
Organic Compounds – always contain large amounts of carbon * theses are the molecules composing living things – organisms
Biologically important Inorganic Molecules
a. Water
Characteristics:
Water and H bond * polar zones of negative and positive charges * known as a weak bond because linking a hydrogen form between the negative corners of one water molecule and positive corners of another
Surface Tension * result of cohesion or clinging together of water molecules * wetting capacity of water is its ability to coat a surface – depends on its capacity to adhere
Capillary Action – causes movements:
Rising (in glass tubes)
Creeping up in a piece of blotting paper
Moving slowly along the micropores of the soil
Imbibition
- movement of water molecules into substances which swell or increase in volume as a result of the interaction between them and the water molecules.
Specific Heat (Specific heat capacity) * the measure of the heat required to increase the temperature of a unit quantity of a substance by a certain temperature interval.
Importance of Water * the universal solvent * component of the most living systems * occupies approximately 75% of the earth’s surface * requirement for photosynthesis
b. Carbon dioxide
- the principal structural element of living matter
Primary requirements of photosynthesis
Waste product of cellular respiration
It forms the backbone for the major molecules of life
c. Nitrogen gas
- comprises 78% of the atmosphere
Primary component of amino acids
d. Oxygen gas
- primary requirement of the cellular respiration
- Product of the
Chemistry
Atoms – smallest particle of an element
Subatomic particles: * Protons * Neutrons * Electrons
Molecules – a unit formed by 2 or more atoms joined together
Elements
Compounds
Mass
Weight
Inorganic Compounds – molecules that do not necessarily contain a carbon
Organic Compounds – always contain large amounts of carbon * theses are the molecules composing living things – organisms
Biologically important Inorganic Molecules
a. Water
Characteristics:
Water and H bond * polar zones of negative and positive charges * known as a weak bond because linking a hydrogen form between the negative corners of one water molecule and positive corners of another
Surface Tension * result of cohesion or clinging together of water molecules * wetting capacity of water is its ability to coat a surface – depends on its capacity to adhere
Capillary Action – causes movements:
Rising (in glass tubes)
Creeping up in a piece of blotting paper
Moving slowly along the micropores of the soil
Imbibition
- movement of water molecules into substances which swell or increase in volume as a result of the interaction between them and the water molecules.
Specific Heat (Specific heat capacity) * the measure of the heat required to increase the temperature of a unit quantity of a substance by a certain temperature interval.
Importance of Water * the universal solvent * component of the most living systems * occupies approximately 75% of the earth’s surface * requirement for photosynthesis
b. Carbon dioxide
- the principal structural element of living matter
Primary requirements of photosynthesis
Waste product of cellular respiration
It forms the backbone for the major molecules of life
c. Nitrogen gas
- comprises 78% of the atmosphere
Primary component of amino acids
d. Oxygen gas
- primary requirement of the cellular respiration
- Product of the