Systems of the Body (1) (ORIENTATION TO THE BODY)

Tissues and Organ Systems

  • Tissue Composition

    • Collections of similar cells constitute tissues.
    • Four basic tissue types are integrated into body walls and visceral structures/organs.

  • Definition of a System

    • A system is a collection of organs and structures sharing a common function.
    • Organs and structures of a single system occupy diverse regions in the body and are not necessarily grouped together.

Skeletal System

  • Components
    • Consists of:
    • Bones
    • Ligaments
    • Function: Provides structure and support to the body, protects internal organs, and allows movement when combined with muscles.

Articular System

  • Definition and Components
    • Comprises both fixed and movable joints.
    • Functions to allow movement and flexibility at the points where bones meet.

Muscular System

  • Components
    • Includes skeletal muscles that move the skeleton and other structures.
    • Contains:
    • Cardiac muscle: pumps blood through the heart.
    • Smooth muscle: moves contents of viscera, vessels, and glands; also involved in securing bones at joints and moving hair on skin.
    • Function: Provides movement, stability, and heat production in the body.

Cardiovascular System

  • Components
    • Composed of:
    • Four-chambered heart
    • Arteries: conduct blood to the tissues
    • Capillaries: facilitate nutrient, gas, and molecular exchange to and from tissues
    • Veins: return blood from the tissues to the heart.
    • Function: Circulates blood throughout the body, delivering nutrients and removing waste.

Lymphatic System

  • Function and Components
    • A system of vessels assisting the veins in recovering the body's tissue fluids and returning them to the heart.
    • Lymph nodes: filter lymph throughout the body, important for immune function.

Nervous System

  • Organization
    • Consists of two main divisions:
    • Central Nervous System (CNS): includes the brain and spinal cord.
    • Peripheral Nervous System (PNS): composed of nerves.
      • The PNS includes:
      • Visceral (autonomic) nervous system: involved in involuntary "fight or flight" responses and vegetative functions.
    • Function: Responsible for generating and conducting impulses; coordinates body activities.

Endocrine System

  • Components
    • Composed of various glands that secrete chemical agents (hormones) into tissue fluids and blood.
    • Functions affected by hormones include metabolic processes and regulation of many areas in the body, including the brain.
    • Hormones help maintain balance in metabolic functions across various body systems.

Integumentary System

  • Components
    • Consists of the skin and associated structures, including:
    • Glands
    • Sensory receptors
    • Blood vessels
    • Immune cells
    • Antibodies
    • Layers of cells and keratin to resist harmful environmental factors.

Orientation to the Body

  • Color Coding for Body Systems
  • Use light colors for illustrations to retain detail.
  • Representations of body systems by color:
    1. Muscular System: Brown
    2. Lymphatic System: Green
    3. Nervous System: Yellow
    4. Endocrine System: Orange
    5. Integumentary System: Color of one’s own skin.
    6. Cardiovascular System:
    • Name remains uncolored.
    • Arteries: Red
    • Veins: Blue
      • Smaller vessels may use varied shades of red and blue.