Chemical Nature of Life

Living organisms vs. nonliving matter
Eight Major Characteristics of Living Organisms:
- Order and Organization: Complexity in structure and function.
- Reproduction, Growth, and Development: Processes that ensure the continuation of species.
- Cells:
  - Contain hereditary material (DNA).
  - Perform metabolism: All biochemical reactions inside a living organism.
- Acquiring and Using Energy: Essential for sustaining life processes.
- Adaptation and Evolution:
  - Adaptations: Traits that enhance survival and reproduction.
  - Evolution: Change over time in response to environmental conditions.
- Homeostasis: Maintaining internal stability despite external changes.
- Relationship between Form and Function: How structure relates to purpose.
- Unity within Diversity: Sharing common characteristics among diverse life forms.

Illustrates the variety seen in living organisms, with examples across a spectrum of complexity from bacteria to sunflowers and octopuses.
Mention of the diversity of life representing various kingdoms and domains.

Biosphere: Regions on Earth that support life (crust, waters, atmosphere).
Ecosystem: Community of organisms interacting with their physical environment.
Community: Interacting populations in a specific area.
Population: Organisms of the same species in a particular setting.
Organism: Individual entity with complex systems.
Organ System: Groups of organs working together.
Organ: Composed of tissues performing specific tasks.
Tissue: Groups of similar cells.
Cell: The basic unit of life.
Molecule: Combinations of two or more atoms.
Atom: Smallest unit of an element, consisting of electrons, protons, and neutrons.

Cell Theory: All organisms are formed of one or more cells; cells arise from other cells.
Evolutionary Theory:
- All organisms share common ancestors.
- Organisms adapt to their environments.
Genetics:
- Organisms contain hereditary information in DNA affecting form, function, and behavior.
Homeostasis: Constant internal environment crucial for life.
Ecosystem Interactions: Organisms interact with other populations and their environment.
Germ Theory: Infectious diseases arise from specific microorganisms.

Matter: Composed of chemical elements; 92 naturally occurring elements plus those synthesized by humans.
Common Elements in Life: Include Sulfur (S), Phosphorus (P), Oxygen (O), Nitrogen (N), Carbon (C), and Hydrogen (H).
Elements such as Sodium (Na), Potassium (K), Calcium (Ca), Magnesium (Mg), Chlorine (Cl), Iron (Fe), and Iodine (I) are also important.

Atoms consist of subatomic particles:
- Nucleus: Contains protons (positive) and neutrons (neutral).
- Electrons: Negatively charged particles orbiting the nucleus.
- Normal atoms have equal protons and electrons, while differences result in ions (charged particles).
- Atoms can be isotopes or radioisotopes depending on neutron count.

Subatomic Particles:
- Proton: +1 Charge, mass of 1 AMU, located in the nucleus.
- Neutron: 0 Charge, mass of 1 AMU, located in the nucleus.
- Electron: -1 Charge, negligible mass, located in electron shells.
Stable atoms have equal protons and electrons.

Key Elements: Carbon (C), Hydrogen (H), Nitrogen (N), Oxygen (O), Phosphorus (P), Sulfur (S).
Examples include isotope notations for Carbon and Nitrogen (e.g., 12C, 14N).

Atoms and molecules strive for stability, leading to various bonding types:
- Ionic Bonds: Formation between ions through electron transfer.
- Covalent Bonds: Bonds formed through sharing of electrons; can be single, double, or triple.
- Electronegativity: Determines bond polarity.

Polar vs. Nonpolar Molecules: Polar molecules can form hydrogen bonds and interact with the water.
Chemical reactions transform reactants into products with electron movements.
Exothermic Reactions: Release energy.

Life's Carbon Basis: All life is carbon-based with stability and reactivity in forming large macromolecules (polymers).
Functional Groups: Characteristic patterns influencing molecular function and bonding.

Summarizes various significant organic functional groups like Hydroxyl, Carbonyl, Carboxyl, Amino, and more, detailing their roles and properties.

Water is the most common substance, crucial for life.
Covalent Bonds: Formed between H and O in water molecules; results in their polarity.

Solvent vs. Solute: Water facilitates biological reactions.
Properties:
- Cohesion: Water molecules bond together.
- Adhesion: Bonds with other polar molecules.
- Specific heat: Water regulates temperature efficiently.
- Capillarity: Ability of water to move through narrow spaces.

Depicts processes like freezing and evaporation, essential in temperature regulation of organisms.

Illustrates pH levels for various substances, understanding acidity and basicity relevant to biological functions.