The Respiratory System Science 10

HOW MANY TIMES DO YOU INHALE AND EXHALE ON AVERAGE IN ONE MINUTE? TRY IT! THE ANSWER IS … 15

The Respiratory System What would cause this number to increase? Physical activity Stress What does the respiratory system do? provide oxygen to the body remove carbon dioxide from the body

Structural Features Nose Mouth Pharynx (throat) The main parts of the respiratory system are: Nose Mouth Pharynx (throat) Trachea (rings of cartilage) Bronchi Lungs

Structural Features nasal cavity mouth ciliated epithelial cells pharynx trachea alveoli bronchus lung bronchioles

Structural Features Cilia in Action Cells that line the trachea and bronchi have cilia (hairlike projections) and cells that produce mucus Cilia and mucus help filter out foreign material that might enter the system Cilia in Action

Pathway of Gases in System Inhale oxygen Oxygen diffuses into blood in the lungs Blood carries oxygen throughout body Oxygen diffuses out of blood into cells Carbon dioxide diffuses out of cells into blood Carbon dioxide travels in blood to lungs Carbon dioxide diffuses out of blood into alveoli Blood picks up oxygen and cycle continues

Gas Exchange the main purpose of the respiratory system is gas exchange each bronchi ends in tiny air sacs called alveoli these sacs allow the diffusion of oxygen and carbon dioxide single alveoli alveoli red blood cells capillary capillary network

Breathing involves alternately bringing air into the lungs (inhalation) and pushing air out of the lungs (exhalation) involves muscles of the ribs and the diaphragm (a large sheet of muscle below the ribs) involuntary process that we can override, but only temporary (try it! how long can you hold your breath for?)

Inhalation and Exhalation

Breathing Inhalation Exhalation volume of the lungs increase muscles of ribs contract diaphragm flattens Exhalation lung volume decreases muscles of ribs relax diaphragm is dome-shaped

Control of Breathing Breathing is controlled by a part of the brain that detects carbon dioxide in the blood As carbon dioxide increases, brain sends signals to the diaphragm, muscles between the ribs, and the heart This increases breath rate and heart rate which decreases the amount of carbon dioxide and increases the amount of oxygen

Diseases of the Respiratory System Tuberculosis An infectious disease caused by bacteria entering body when you breathe Symptoms: fever, cough, weight loss, tiredness, chest pain Cancers Caused by tobacco smoke SARS Symptoms are flulike Respiration Video

Amazing Facts About the Respiration System The right lung is slightly larger than the left. Hairs in the nose help to clean the air we breathe as well as warming it. The highest recorded "sneeze speed" is 165 km/h The surface area of the lungs is roughly the same size as a tennis court. The capillaries in the lungs would extend 1,600 kilometres if placed end to end. We lose half a litre of water a day through breathing. This is the water vapour we see when we breathe onto glass. The breathing rate is faster in children and women than in men.

Textbook Questions Answer Pg. 95 #1 – 6

CYL 1 – 6 pg. 95 Name the main organs and structures of the respiratory system. nasal cavity pharynx mouth trachea bronchi lungs alveoli

CYL 1 – 6 pg. 95 What is the role of the epithelial tissue that lines the trachea and bronchi? secrete mucus and filter out foreign material How does an animal’s respiratory system depend on its circulatory system? circulatory system carries oxygen and carbon dioxide that are exchanged in respiratory system

CYL 1 – 6 pg. 95 Explain the difference between breathing and gas exchange. breathing is intake and output of air gas exchange involves diffusion of oxygen into the blood and carbon dioxide out of the blood

CYL 1 – 6 pg. 95 (a) Why is an x-ray insufficient to make a positive diagnosis of tuberculosis? an x-ray can show TB, but other conditions (such as pneumonia) can look like TB on an x-ray (b) What test is required to confirm a diagnosis of TB? stomach and lung secretions must be examined to confirm TB

CYL 1 – 6 pg. 95 Describe the similarities and differences between the respiratory systems of humans and fish. both exchange oxygen and carbon dioxide fish takes in oxygenated water, humans take in air humans breathe air in and out for gas exchange, in fish gas exchange occurs as water flows over their gills