human body system

• The Digestive System


  1. Converts food into simpler molecules that can be used by cells

  2. Absorbs food

  3. Eliminates waste

  
• The entire digestive process takes between 24 and 33 hours
• The Excretory System


  Eliminates waste products from the body
• The Respiratory System


  1. Provides oxygen needed for cellular respiration

  2. Removes carbon dioxide from the body

  
• The Circulatory System


  1. Brings oxygen, nutrients and hormones to cells

  2. Fights infections

  3. Removes cell wastes

  4. Regulates body temperature

  
• The Skeletal System


  • Supports the body
  • Protects internal organs
  • Allows movement
  • Stores mineral reserves
  • Provides blood cell formation

  
• The Muscular System


  1. Produces voluntary movement

  2. Circulates blood

  3. Moves food through digestive system
• The Nervous System


  Recognizes and coordinates the body's response to changes in its internal and external environments

  
• The Integumentary System


  • Barrier against infections and injury
  • Regulates body temperature
  • Protects against ultraviolet radiation
• The Immune System


  1. Helps protect the body from disease

  2. Collects fluid lost from blood vessels and return it to the circulatory system

  
• The Endocrine System


  1. Controls growth, development, and metabolism

  2. Maintains homeostasis
• Hypothalamus


  Part of the brain that the main link between the endocrine and nervous systems

  
• Pituitary


  The main gland of the endocrine system. It is stimulated by the hypothalamus when changes in homeostasis are detected and produces chemicals and stimulates other glands.

  
• Thyroid


  • Produces thyroxin, the main growth and metabolic hormone
  • Also regulates calcium levels in the blood
• Parathyroid


  • Regulates minerals by producing PTH (parathyroid hormone)
• Adrenal Glands


  • Prepare the body for stress by releasing hormones epinephrine (adrenaline) norephinephrine which increases blood pressure and heart rate
  • Produce corticosteroids that influence or regulate salt and water balance in the body
• Pancreas


  • Produces two important hormones insulin and glucagon: they work together to maintain a steady level of glucose, or sugar, in the blood and to keep the body supplied with fuel to produce and maintain stores of energy
• Ovaries


  • Secrete female sex hormones
• Testes


  • Secrete male sex hormones
• The Reproductive System


  1. Produces reproductive cells

  2. In females nurtures and protects developing embryo
• On-Level Biology Book: Pg 893 – 898
• Pre-AP Biology Book: Pages 933 - 941