Human Anatomy and Physiology

Brain

• Control center of the body, protected by the skull.
• Cerebrum: Largest part, divided into two hemispheres by the corpus callosum.
  • Frontal Lobe: Thinking, self-control, decision making, attention, judgment, problem-solving, planning, emotions, motor skills, speech production.
  • Parietal Lobe: Organizes and interprets sensory information.
  • Occipital Lobe: Visual processing (shapes, colors, patterns, motion), reading.
  • Temporal Lobe: Auditory processing, visual/verbal memory, language comprehension, emotional recognition.
  • Cerebellum: Fine motor skills, balance, coordination, posture.
  • Brain Stem: Connects to the spinal cord; controls basic functions like eye movement, breathing, swallowing.
    • Midbrain: Processes visual and auditory information.
    • Pons: Connects different parts of the brain, facial movement.
    • Medulla Oblongata: Controls heart and lungs functions.

Lungs

• Part of the respiratory system, providing oxygen to the bloodstream and removing carbon dioxide.
• Protected by the rib cage, comprising the trachea, bronchi, bronchioles, and alveoli.
• Alveoli: Gas exchange occurs with blood capillaries; oxygen diffuses into blood, carbon dioxide out.

Heart

• Vital organ of the circulatory system; double circulation system.
  • Right atrium & ventricle: Pumps deoxygenated blood to the lungs.
  • Left atrium & ventricle: Pumps oxygenated blood to the body.
  • Valves: Ensure one-way blood flow (tricuspid, pulmonary, mitral, aortic).
  • Veins: Carry blood to the heart (superior/inferior vena cava, pulmonary vein).
  • Arteries: Carry blood away from the heart (aorta, pulmonary artery).
  • Coronary arteries: Supply the heart muscle with oxygenated blood.
  • Two phases: Diastole (heart relaxes and fills with blood) & Systole (heart contracts and pumps blood).

Spleen

• Small organ beneath the stomach; stores and filters blood, removes old/damaged cells, and produces white blood cells for infection control.

Stomach

• Role in digestion; divided into five parts (cardia, fundus, body, pyloric antrum, pyloric canal).
  • Muscles and gastric juices help break down food.
  • Food passes through sphincter muscles to prevent backflow, mixes with gastric juices, then exits to the small intestine.

Pancreas

• Located behind the stomach; has exocrine (digestive enzymes) and endocrine (regulates blood sugar) functions.
  • Produces insulin and glucagon to regulate blood sugar levels.

Liver

• Crucial for metabolic processes; located under the rib cage near the gallbladder.
  • Purifies blood, processes nutrients, detoxifies toxic substances, produces plasma proteins, cholesterol, bile.
  • Bile: Aids digestion, stored in the gallbladder.

Gallbladder

• Small green pouch under the liver, stores bile which aids in digesting fats.

Kidneys

• Two bean-shaped organs; maintain chemical balance by filtering blood and excreting waste as urine.
  • Nephrons: Units for filtration; balance water levels; secrete hormones; activate Vitamin D.

Small and Large Intestines

• Tubes that digest food, filter waste, and absorb water.
  • Small intestine: Main site for digestion and nutrient absorption.
  • Large intestine: Absorbs water and salts, forming solid waste for excretion.

Bladder

• Part of the urinary system; stores urine produced by kidneys, made of muscle which stretches to accommodate urine and contracts to release it via the urethra.

• Urine Color: Indicator of hydration; lighter when hydrated, darker when dehydrated.