Fundamentals of Biology: Energy, Atoms, Molecules, and Systems

Energy and Its Forms

Energy is the ability to cause changes. There are two kinds:

  • Potential Energy: Unactualized energy.
  • Kinetic Energy: Active energy. Examples include heat, electricity, light, and movement. Potential energy includes gravity and chemical energy.

Atoms and Molecules

Atoms are the smallest unit of an element (e.g., Oxygen, Hydrogen, Nitrogen, Carbon, Iron).

Subatomic Particles and Molecules

Subatomic Particles (protons, neutrons, and electrons) together make up atoms, which form molecules.

Molecules are of two kinds:

  • Organic Molecules: Carbon compounds like sugar, fiber, and aspirin.
  • Inorganic Molecules: Water, carbon dioxide, sulfur dioxide, and salt.

Biomolecules (4 Major): Proteins, sugars, lipids, and nucleic acids.

Cells and Tissues

Molecules and macromolecules together form cells.

  • Cell Membrane: The outer covering of a cell.
  • Cytoplasm: The inside of a cell.
  • Nucleus: The center of a cell.

Organelles

  • Ribosomes: Produce protein.
  • Mitochondria: Produce energy.
  • Lysosomes: Handle waste disposal.

Tissues

Nerve, connective, epithelial, and muscle tissues.

Organs and Organ Systems

Tissues together form organs. Organ systems include:

  • Nervous System
  • Digestive System
  • Respiratory System
  • Cardiovascular System
  • Urinary System

Organ systems make up organisms.

Populations, Communities, and Ecosystems

  • Populations: A group of organisms of the same species.
  • Communities: A group of populations.
  • Ecosystems: A group of plants, animals, and other living systems interacting with each other and their environment.
  • Biomes: A number of closely related ecosystems.
  • Biosphere: Atmosphere, thermosphere, hydrosphere, lithosphere, mesosphere, etc.

Cardiovascular/Circulatory System

  • Heart: Made up of left and right ventricles and left and right atria (pump).
  • Blood Vessels: Arteries, arterioles, capillaries, ventricles, and veins.
  • Blood: Made up of plasma, red cells, white cells, and platelets.

Lymphatic/Immune System

Consists of lymph organs (spleen, thymus, lymph nodes) and lymph (fluid consists of white blood cells).

Function: Immunity; collects and returns some tissues and fluids to the bloodstream. Defends the body against infection and tissue damage.

Digestive System

Consists of the oral cavity, esophagus, stomach, small intestine, rectum, and anus. It ingests food and water mechanically, breaks down food and absorbs small molecules into the internal environment, and eliminates food residues.

Respiratory System

Consists of the nasal cavity, trachea, and lungs. Rapidly delivers oxygen to the tissue fluid that bathes all living cells. Removes carbon dioxide wastes from all cells and helps regulate pH.

Urinary System

Consists of kidneys, ureters, urinary bladder, urethra, and urine. Maintains the volume and composition of the internal environment and excretes excess fluid and blood-borne wastes.

Nervous System

Central Nervous System: Brain and spinal cord. Includes chemical senses, sense of vision, hearing, and balance.

Skeletal System

Bones provide movement, support, and protect body parts.

Muscular System

Muscles move the body and internal parts, maintain posture, and generate heat by increases in metabolic activity.

Endocrine System

Consists of glands and hormones. Controls body function with the nervous system and integrates short-term and long-term activities.

Matter and Mixtures

Matter: Anything that has mass and volume.

  • Pure Substance: Only one kind of matter.
  • Mixture: More than one kind of matter.

Mixtures

Made up of more than one kind of matter.

  • Homogeneous: The same throughout and consists of one phase.
    • Solution: Air, coke, coffee, alloy.
    • Colloid: Mist, Jell-o, Mayo.
    • Suspension: Mud, Blood.
  • Heterogeneous: Has more than one phase. Pizza, vinegar, oil, sand, and salt.

Pure Substances

Made up of one kind of matter.

  • Element: Made up of one kind of atom (Iron, Sodium, Oxygen, Hydrogen, Carbon).
  • Compound: Made up of more than one kind of atom (Inorganic – Water, Carbon Dioxide; Organic – Methane, Sugar).