It has two videos which are not playing . If you want to add videos you can download it from the link given below. For plants: http://www.youtube.com/watch?v=s44RQi_P7kQ For animals: http://www.youtube.com/watch?v=EhnRhfFLyOg

1. BY- ZAID ALAM
CLASS- IX – F
ROLL NO.- 36

2. • INTRODUCTION.
• EXCRETION IN PLANTS.
• EXCRETION IN ANIMALS.
• NEPHRON.
• HEMODYLASIS.
• SITES PREFERRED.

3. INTRODUCTION
 The biological process involved in removing the harmful nitrogenous waste
from the body is called excretion. Excretion takes place in plants and
animals. Different organisms use different strategies to eliminate this
waste, i.e. to perform excretion The waste that is eliminated is toxic and
can be harmful if stays within the body. Thus to eliminate this waste
excretion is essential. As in the other processes complex multi cellular
organisms use different organs to do the same process.

4. EXCRECTION IN PLANTS
 Plants have less complex structure than animals, and have their own
means of excretion. Plants eliminate some waste through diffusion. During
the day, excess oxygen gas produced by photosynthesis is released
through the stomata. Carbon dioxide produced by respiration is normally
used up during photosynthesis. At night, however, as photosynthesis
slows, carbon dioxide is not used up as fast as it is produced, and it is
released as a waste product. Plants also produce oxygen as a by-product
of photosynthesis. The oxygen that is not used for respiration is also
excreted through the stomata. Plants also eliminate waste by the
accumulation of waste in the vacuoles of the aging leave cells. These
leaves will eventually die and fall off, removing waste in the process. Trees
also excrete in the form of sticky, milky or oily substances from the bark of
trees. These are excretory products and may be resins, gums, latex and or
other excretory products. These products maybe poisonous, however
many have found use in everyday life of humans, such as latex which is
used to produce gloves and clothing. Plant also excrete the waste products
into the soil around them.

5. VIDEO

6. EXCRETION IN ANIMALS
 Unicellular organisms like amoeba throw out their wastes by diffusion from
their body surface. Protozoan’s have no organs for excretion. As they live in an
aquatic habitat, their wastes are eliminated by diffusion through the plasma
membrane. Simple multicellular organisms like Hydra throw out solid waste
matter through their mouth. Higher multicellular organisms have well-defined
specialized excretory organs. These organs could be simple tubular structures
as in flatworms and leech. The excretory organs of insects (e.g., grasshopper,
cockroach and housefly) are also tubular. They remove nitrogenous wastes
from the body fluid and help in maintaining the water balance in the body. In
vertebrates, the main organs of excretion and maintenance of water balance
are the kidneys.
 EXCRETION IN HUMAN BEINGS :
The Excretory System of humans is made up of 4 structures: two kidneys,
two ureters, a bladder, and the urethra. The kidneys act as a filter to filter
the waste products from the blood, the ureters are tubes that transport the
main waste products (urine) from the kidneys to the bladder, where it is
stored until it is excreted out of the body through the urethra.

7. The kidneys are located one on each side of the vertebral column just
below the diaphragm. Each kidney is bean shaped with a concavity on the
inner margin. Blood vessels, nerves and ureters arise from the kidney at
this point. Kidneys are the urine-forming organs of human beings. Urine
formed in the kidneys passes down thin muscular tubes called ureters.
Ureters from both the kidneys open into a muscular sac called urinary
bladder. Bladder is a storage sac that releases the urine to the outside
through a short tube called urethra. Each kidney is composed of numerous
tiny filters called nephron. Nephrons are the functional units of kidneys.
Each nephron is a ling-coiled tubular structure the filters out nitrogenous
waste material from the blood and forms urine. Urea is the main
nitrogenous waste present in urine. Kidneys must function properly in
order to keep a person in perfect health.

8. USE OF NEPHRON
 Nephron, is the basic structural and functional unit
of the kidney. Its chief function is to regulate the
concentration of water and soluble substances like
sodium salts by filtering the blood, reabsorbing
what is needed and excreting the rest as urine.
A nephron eliminates wastes from the body,
regulates blood and regulates blood pH.
The nephron carries out nearly all of the kidney's
functions. Most of these functions concern the
reabsorption and secretion of various solutes such
as ions (e.g., sodium), carbohydrates (e.g., glucose),
and amino acids (e.g., glutamate). Properties of the
cells that line the nephron change dramatically along
its length; consequently, each segment of the
nephron has highly specialized functions.

9. VIDEO

10. HEMODIALYSIS
 Hemodialysis is a process that uses a man-made membrane (dialyzer)
to remove wastes, such as urea, from the blood and to store the proper
balance of electrolytes in the body. It also eliminate extra fluid from
the body.

11. • http://www.youtube.com/watch?v=EhnRhfFLyOg
• http://www.youtube.com/watch?v=-9fePvlAHd8
• http://www.authorstream.com/Presentation-excretion
• http://en.wikipedia.org/wiki/Excretion
• http://en.wikipedia.org/wiki/Excretory_system
• http://www.britannica.com/topic/409282/nephron