Life Processes: Excretion

Definition: The process of removing waste and excess substances from the body
Importance: Maintains homeostasis, prevents toxin buildup, and regulates electrolyte balance
Organs involved:
- Kidneys: filter waste and excess substances from blood
- Liver: detoxifies and converts toxins into waste
- Skin: removes waste through sweat
- Lungs: removes carbon dioxide
- Intestines: absorbs nutrients and eliminates waste
Excretory products:
- Urine
- Feces
- Carbon dioxide
- Sweat

Definition: The process of moving substances within the body
Importance: Supplies oxygen and nutrients to cells, removes waste products
Transportation systems:
- Circulatory system (blood vessels, heart): transports oxygen, nutrients, and hormones
- Lymphatic system: transports immune cells, fats, and proteins
- Nervous system: transmits signals and coordinates body functions
Modes of transportation:
- Blood circulation
- Lymphatic circulation
- Diffusion (cell membrane)
- Osmosis (water transport)

Definition: The process of obtaining and utilizing energy and nutrients
Importance: Provides energy, builds and repairs tissues, and maintains health
Nutrient types:
- Carbohydrates (energy source)
- Proteins (building blocks)
- Fats (energy storage)
- Vitamins and minerals (regulate metabolism)
Nutrient uptake:
- Ingestion (eating)
- Digestion (breaking down nutrients)
- Absorption (into bloodstream)
- Assimilation (utilization by cells)

Definition: The process of exchanging oxygen and carbon dioxide
Importance: Provides energy, maintains pH balance, and regulates oxygen levels
Respiratory system:
- Nose and mouth: air entry points
- Trachea: airway
- Bronchi and bronchioles: air tubes
- Alveoli: gas exchange site
Respiratory process:
- Inspiration (inhalation): oxygen entry
- Expiration (exhalation): carbon dioxide removal
- External respiration (breathing)
- Internal respiration (cellular respiration)

Moves substances within the body to supply oxygen and nutrients to cells and remove waste products
Circulatory system transports oxygen, nutrients, and hormones through blood vessels and the heart
Lymphatic system transports immune cells, fats, and proteins
Nervous system transmits signals and coordinates body functions
Modes of transportation include blood circulation, lymphatic circulation, diffusion, and osmosis

Obtains and utilizes energy and nutrients to provide energy, build and repair tissues, and maintain health
Carbohydrates are energy sources
Proteins are building blocks
Fats are energy storage
Vitamins and minerals regulate metabolism
Nutrient uptake involves ingestion, digestion, absorption, and assimilation

Exchanges oxygen and carbon dioxide to provide energy, maintain pH balance, and regulate oxygen levels
Respiratory system includes nose and mouth, trachea, bronchi and bronchioles, and alveoli
Inspiration (inhalation) brings oxygen into the body
Expiration (exhalation) removes carbon dioxide
External respiration involves breathing
Internal respiration involves cellular respiration

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