Upload
others
View
14
Download
0
Embed Size (px)
Citation preview
32 Excretion.notebook
R.Cummins 1
April 28, 2013
Chapter 32 ExcretionExcretion is the getting rid of waste products of metabolism.
The main excretory organs are:
• lungs (water and carbon dioxide)
• skin (water and salts)
• kidneys (water, salts, and urea)
32 Excretion.notebook
R.Cummins 2
April 28, 2013
EpidermisThe outer layer is dead, cornified, and full of waterproof keratin.The inner layer has living, granular cells.The Malpighian layer makes new cells and contains cells with melanin.
Skin
Temperature RegulationThe skin cools the body with open pores and sweat and keeps the body warm by erecting hairs to close the pores (goosebumps).
DermisThese cells contain a strong protein called collagen and has many blood vessels, sweat glands, hairs, sebaceous glands, and nerve receptors.
32 Excretion.notebook
R.Cummins 3
April 28, 2013
Functions of the Skin
32 Excretion.notebook
R.Cummins 4
April 28, 2013
The Urinary System
The urinary system consists of two kidneys, two ureters,
the bladder, and urethra.
32 Excretion.notebook
R.Cummins 5
April 28, 2013
The Kidneys
32 Excretion.notebook
R.Cummins 6
April 28, 2013
Nephrons Higher LevelThese carry out the functions of the kidneys and are
located in the cortex and medulla of the kidney.
32 Excretion.notebook
R.Cummins 7
April 28, 2013
Reabsorption
Water is reabsorbed by Osmosis.Salt is reabsorbed by diffusion
and active transport.
32 Excretion.notebook
R.Cummins 8
April 28, 2013
Urine Volume ControlADH (AntiDiuretic Hormone): is released from the pituitary gland and controls the volume of urine formed.
Lack of water in the blood plasma stimulates ADH.It causes water to be reaborbed and less urine is made.