Systems of the Body (2) (ORIENTATION TO THE BODY)

Respiratory System

• Consists of two main parts:
  • Upper respiratory tract:
  • Comprises structures from the nose to the larynx.
  • Lower respiratory tract:
  • Extends from the trachea to the air spaces of the lungs.
• Function:
  • The primary function of the respiratory system is gas exchange, facilitated by structures within the airway and alveoli.
  • Alveoli:
  • Tiny air sacs where gas exchange occurs between the alveoli and lung capillaries.

Digestive System

• Structure:
  • Composed of the alimentary canal and associated glands.
  • Glands include:
  • Liver
  • Pancreas
  • Biliary system (gallbladder and related ducts)
• Function:
  • Responsible for the breakdown, digestion, and assimilation of food.
  • Process of Excretion:
  • Excretes residual material from the digestive process.

Urinary System

• Function:
  • Maintains water conservation and a neutral acid-base balance in body fluids.
• Key Organs:
  • Kidneys:
  • Main organs responsible for filtering blood and producing urine.
  • Ureters:
  • Tubes that carry urine from the kidneys to the urinary bladder.
  • Urinary Bladder:
  • Holds urine until it is excreted.
  • Urethra:
  • Duct through which urine is discharged from the urinary bladder to the outside of the body.

Immune/Lymphoid System

• Function:
  • Comprises multiple organs that are essential for body defense against disease.
• Key Components:
  • A diffuse arrangement of immune-related cells throughout the body.
  • These immune cells resist invaders (like microorganisms) and help to remove damaged or abnormal cells.

Female Reproductive System

• Functions:
  • Hormone Production:
  • Secretes female sex hormones.
  • Germ Cell Production:
  • Produces and transports germ cells (ova).
  • Fertilization:
  • Receives male germ cells and facilitates their transport to the fertilization site.
  • Embryo Development:
  • Maintains the developing embryo/fetus and supports it until birth.

Male Reproductive System

• Functions:
  • Hormone Production:
  • Secretes male sex hormones.
  • Germ Cell Production:
  • Forms and maintains germ cells (sperm).
  • Cell Transport:
  • Transports male germ cells to the female genital tract for fertilization.