Download Excretory organs

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Index
Nervous system
Brain
Spinal cord
Nerves
Respiratory organs
Trachea or windpipe
Bronchial tubes
Lungs
Excretory organs
Kidneys
Urinary bladder
Digestive organs
Oesophagus
Stomach
Intestine ( small and large )
Locomotory system
Bones in general
Others
Skull
Ribcage
Spinal column
Muscles
Circulatory system
Heart
Arteries and Veins
Blood
Liver
Gall bladder
Skin
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Bibliography
Biology book ( Bau und Funktionen unseres
Körpers )
Sheets distributed from the secondary
school
Sheets distributed from the grammar school
Pictures
Google pictures
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Nervous system
Brain
The brain is the most important and developed central of the nervous system.
The brain demands a lot of oxygen and has to be supplied with blood.
It is the controlling headquarter of the body. The brain coordinates body
functions and tells muscles when they have to contract. It also allows humans to
think.
Spinal cord
The spinal cord is embedded in the spinal column. It is also a part of the
controlling headquarter of the body. The spinal cord coordinates the body
functions and tells muscles when they have to contract.
Nerves
They convey signals. Sensitive nerves bring the information from the body
surface and from the sensory organs to the brain and to the spinal cord. These
two centres process the received messages and release commands. The motor
nerves conduct the order signals to the muscles and to the glands.
They bring the information from the sensory organs to the
brain (afferent nerves ) and commands from the brain to the
muscles ( efferent nervers ).
Respiratory organs
Trachea or windpipe
The trachea or wind pipe is twelve centimeter long. Inside it is undressed with a
mucous layer. The mucosa cells have cilias. The cilias beat constantly against the
pharynx. The cilias convey outwards little impurities.
This pipe brings inhalated air from the outside to the lungs and exhalated air
CO2 out of the lungs.
Bronchial tubes
At the hight of the fourt throracis vertebra the windpipe is separated in two
branches ( stem bronchi ). Each stem of bronchi lead into one of the lungs. The
bronchi ramify and separates into branches.
The bronchial tubes are the two branches which together form the trachea and
connect it with the right and the left lung.
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Lungs
The oxygen hikes from the breathing air into the blood and the carbon dioxide
hikes from the blood into the alveoles. The lungs perform the gas exchange
between the blood and the inhalaited air: Oxygen is taken up into the blood and
carbon dioxide is delivered from the blood into the air.
Excretory organs
Kidneys
They are surrounded by a fatty layer. The kidney excretes waste material. Before
the excretion the waste material has to be filtered and transfered into urine.
Urinary bladder
The urinary bladder collects urine, which is produced by the reins, in the urinary
bladder. Urine is excreted from the body. This means a human needs to urinate.
Digestive organs
Oesophagus
The oesophagus is a muscular tube with longitudal creases on the inside. It lies
behind the windpipe, breaks through the diaphragm and leads to the stomach.
The oesophagus brings the food into the stomach.
Stomach
It lays on the left side of the body below the diaphragm. The stomach has an
entrance ( stomach mouth ) and an exit ( pylorus ). The stomach holds two liters
stomach pulp. The smooth musculature of the stomach wall contracts like waves
and kneads the stomach pulp. The gastric acid kills with the food
penetrated bacteria. The stomach is the first station of food digestion.
Intestine
( small and large )
In this organ, food is dissassembled to its building blocks
( = digestion ) and then taken up into the blood
( resorption ).
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Locomotory system
Bones in general
The bones prop the body and enable its posture. They give the body its shape and
are starting points for the muscles. The bones protect important organs.
Others
Skull
The skull protects the most important central of the nervous system. It protects
the brain.
Ribcage
The ribcage protects important organs like heart, lungs, liver and spleen.
Spinal column
The spinal column protects the spinal cord.
Muscles
The muscles allows active movements.
Circulatory system
Heart
The heart lies protected under the costals and the sternal. Two thirds lie on the
left side and one third lies on the right side of the body. The heart is embedded in
a bag with lubricating fluid.
The heart is a muscle with four hollows. The left and the right heart chambers
are thick-walled and perfom most of the work. The two atria present a thin wall.
Sail flaps prevent the back flow of the blood. The sail flaps are between the atria
and the heart chambers. The pocket flaps prevent that the blood beats back from
the arteries.
The muscle relaxes ( diastole ) and the cavity fills with blood. The muscle
contracts ( systole ) and presses out the blood.
The heart pumps the blood through the blood vessels.
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Arteries
The thicked-walled arteries carry away the blood from the heart to the organs. It
flows intermittently. The thick walls are reinforced by elastic fibres and smooth
muscles. The fibres and the muscles help moving forward the blood.
Veins
The thined-walled veins transport the blood from the organs back to the heart.
The blood flows evenly. Valves prevent that the blood beats back. If arteries and
muscles press on the vein wall, they help moving forward the blood.
Blood
Blood is the most important transportation of our body. It brings nutrients and
oxygen to all cells of our body. The blood brings waste material from the cells to
the excretory organs. Heat is also transported by the blood. The blood is the
transportation of hormones.
Liver
The liver stores excess blood sugar in form of glycogen. The cyglogen is available
for the body at a high demand of the nutrients. The liver detoxicates the body
from alcohol, aspirine or caffeine. Nicotine, alcohol and other toxins are rended
harmless. The liver is a blood reservoir. It breaks down red blood cells.
Gall bladder
Collects the bile ( yellowish fluid ) which is produced by the liver and helps
digestion.
Skin
The skin protects the body against dehydration, injuries, sunbeams, coldness
and heat. The skin is a sensory organ and is the body’s protective cover.
The skin consists of three layers:
Epidermis
Dermis
Hypodermis
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