Chapter 13…Respiration & Excretion

 

Students should be able to:

 

·        Define  the role of the respiratory system

·        Explain why cells need oxygen and give  off carbon dioxide

·        Compare the respiratory system of different animals

·        Give the function of different parts of the respiratory system

·        Compare  the pathways of gases as they enter and leave the body

·        Sequence  the movement of the diaphragm and the rib cage during the breathing process  

·        Relate  the effects of carbon monoxide poisoning and how to avoid the gas .

·        Explain the cause of pneumonia .

·        Describe emphysema

·        Discuss the importance of the excretory system.

·        Sequence the steps for filtering of blood in the kidney .

·        Describe the skin as part of the excretory system.

 

 

Chapter Outline

 

1.     The main role of the respiratory system is to supply the body with Oxygen and get rid of carbon dioxide

 

2.     The main source of energy for the body is cellular respiration which cannot go on with out oxygen and it  produces carbon dioxide that must leave the body ,so the respiratory system is the gate to get oxygen into the body and to get rid of Carbon dioxide

 

3.     Animals may breath  (Exchange gases) through gills (fish) , lungs ( humans) , skin ( Earthworm) ,air tubes (Grasshopper) or both skin and lungs ( Amphibians)

 

4.     Human Respiratory System: inwards -> Nasal Chamber > Larynx ( Voice Box) > Trachea > Bronchi > Bronchioles > Alveoli ( Small air sacs through which gas exchange take place between lungs and blood)

 

5.     Breathing Process:

 

a.     Breathing in : Diaphragm and ribs muscles contract  > lungs volume increase > pressure inside lungs decrease > air moves in …Inhaling air

 

b.      Breathing out : Diaphragm and ribs muscles relax  > lungs volume decrease > pressure inside lungs increase > air moves out …Exhaling air

 

6.     Breathing Problem: Carbon monoxide: is a poisonous gas that  results from incomplete combustion and it competes with Oxygen preventing O2  transportation by blood

 

7.     Breathing Diseases:

 

a.     Emphysema : Is a lung disease that results in the breakdown of alveoli  ( not enough oxygen into the blood) , and it results from breathing in chemicals from smoking or air pollution that is why it is not communicable.

 

b.     Pneumonia : Is a lung disease caused by a bacteria , a virus or both that  results in extra mucus in alveoli which cause difficulty in breathing

 

8.     Excretion  is the removal of chemical wastes from the body , one of these chemical wastes is liquid wastes  which can be excreted  through skin ( jellyfish), tubes (Earthworm), or kidneys (humans)

 

9.     Excretion of liquids through the Urinary System : wastes filtered by the kidneys (which contains millions of tiny filtering units called Nephrons) > to the ureters >  collected in the urinary bladder > released via the urethra to the outside

 

10.            Liquid wastes are also known as Urine which is mainly water , Excess water, Excess salts , other chemicals, and Urea , Uric Acid, or Ammonia

 

11.            Skin has three main jobs:

 

a.     Protects the body : due to the outer layer that is made up of dead water proof layer of cells

b.     Sense Organ: due to the nerve endings

c.      Excretion of sweat ( water and salts) as wastes  which is also for thermal regulation (a way to cool the body)

 

12.            Problems of the Excretory system :

 

a.     Infection of the kidney caused by bacteria

b.     Kidney stones

 

 

 

Lab:  Dissection of the Kidneys         Study Guide Papers  73-78