Important Vocabulary  Excretion: The process which metabolic wastes are eliminated to maintain homeostasis.  Ureters: Transport urine from the kidneys to the urinary bladder  Urinary bladder: Store urine until it is released through the urethra  Urethra: Where urine is released

Excretory System’s Function  Excretes metabolic wastes from the body.

Structures of the Excretory System  Skin  Lungs  Liver  Kidney

Structures of the Excretory System  Kidney: The major organ of excretion. Excretes excess water, urea and metabolic wastes from the blood. Produce and excrete a waste product known as urine. Ureters transport urine from kidneys to the urinary bladder, where the urine is stored until it is released through the urethra.

 Wastes enters through renal artery Exits through renal vein  Nephrons: Individual processing units of kidneys.  Maintain blood pH  Regulate blood volume

The Kidneys and Homeostasis  Kidneys play important role in maintaining homeostasis  The kidneys responds directly to the composition of the blood. They are also influenced by the endocrine system. Disruption of proper kidney function can lead to serious health problems.  Kidney Disorders  Kidney Stones  Kidney Damage  Kidney Failure

Functions  Converts food into small molecules that can be used by the cell.  Food is processed by the digestive system in 4 phases.

4 Phases of the Digestive System  1) Ingestion- getting food into the system through your mouth  2) Digestion- food is broken down 2 ways a) Mechanical- physical breakdown of large pieces of food b) Chemical- enzymes break down food into the small molecules

 3) Absorption- absorbed by cells in the small intestine  4) Elimination- travel through large intestine and eliminated from the body

Process/What Occurs  Food travels through the mouth, esophagus, stomach, and small intestine.

Process/What Occurs  Mouth/Teeth- perform mechanical digestion  Saliva- moisten food, make it easier to chew, begins process of chemical digestion  Esophagus- a tube that leads food into the stomach  Stomach- muscular sac continues chemical and mechanical digestion  Small Intestine- chemical digestion and absorption of the food  Pancreas- gland that produces hormones that regulate blood sugar levels, breaks down carbs, proteins, lipids, nucleic acids, produces sodium bicarbonate  Liver- produces bile, releases bile into small intestine, breaks down fats

Absorption & Elimination  Small Intestine- absorbs nutrients into lining of small intestine (carbs & protein)  Large Intestine- removes water from the undigested material left over  Feces removed from the body through the anus