Respiratory System
Functions Moves oxygen from the outside environment into the body Removes carbon dioxide & water from the body
Organs Nose - primary upper respiratory organ in which air enters into and exits from the body Nose - primary upper respiratory organ in which air enters into and exits from the body –Cilia and mucus line the nasal cavity and traps bacteria and foreign particles that enter in through the nose. Pharynx - tubular structure, that allows air to pass from the mouth to the lungs Pharynx - tubular structure, that allows air to pass from the mouth to the lungs Larynx -part of the upper respiratory tract that has two main functions: a passageway for air to enter into the lungs, and a source of vocalization Larynx -part of the upper respiratory tract that has two main functions: a passageway for air to enter into the lungs, and a source of vocalization
Organs Bronchi -allow the passage of air to the lungs Bronchi -allow the passage of air to the lungs Lungs- spongy, air-filled organs located on both sides of the chest cavity Lungs- spongy, air-filled organs located on both sides of the chest cavity Alveoli- tiny grape-like sacs at the end of the respiratory tree Alveoli- tiny grape-like sacs at the end of the respiratory tree Diaphragm- muscular structure located between the thoracic and abdominal cavity. Contraction of the diaphragm causes the chest or thorax cavity to expand Diaphragm- muscular structure located between the thoracic and abdominal cavity. Contraction of the diaphragm causes the chest or thorax cavity to expand
Bronchi
Why the body needs oxygen chemical reactions inside the cell require oxygen Respiration – the process in which cells break down simple food molecules to release the energy they contain
The Air You Breathe 21% oxygen 21% oxygen 78% nitrogen 78% nitrogen 1% carbon dioxide, helium, & other gases
The Path of Air NOSE nostrils – 2 openings lining contains blood vessels that warms the air mucus – moistens the air keeps tissue from drying out, traps particles
Cilia – hair-like projections that move in a wavelike manner on the outside of cells that sweep mucus into the throat Sneeze – if the lining of the nose or throat is irritated sneeze to get the irritants out
2. pharynx throat shared with the digestive system
3. trachea “windpipe” tube with a series of ridges (rings of cartilage) cartilage strengthens the trachea & keeps it open lined with cilia & mucus that clean & moisten the air cough – irritants in the lining of the trachea
4. bronchi & lungs passages that direct air into lungs divides into smaller & smaller tubes inside the lungs – like tree branches
alveoli – tiny sacs of lung tissue specialized for the movement of gases between air & the blood (resemble bunches of grapes) alveoli are surrounded by capillaries lungs are the main organ of the respiratory system
Alveoli
How gas exchange occurs air enters alveolus blood flowing through capillaries surround the alveolus oxygen passes through the wall of the alveolus & wall of capillary oxygen binds to hemoglobin carbon dioxide is released
Function of a large surface area adult lungs contain ~300 million alveoli large surface area allows lungs to absorb a large amount of oxygen
How you breathe breathe ~20,000 times a day Diaphragm – large dome-shaped muscle
Diaphragm
inhale rib muscles contract chest wall moves up & out diaphragm contracts & moves downward chest cavity is larger & the lungs can expand (there’s more room for air) pressure inside the lungs decreases
air is pushed into the lungs by the imbalance of atmospheric pressure exhale rib muscles & diaphragm relax chest cavity becomes smaller air is pushed out of lungs
How You Speak Larynx – “voice box” underneath the epiglottis Vocal cords – folds of connective tissue that stretch across the opening of the larynx & that produce voice
Vocal cords Laryn x
Muscles make the vocal cords contract narrow the opening Air rushes through the opening movement of the vocal cords makes the air molecules vibrate sound Length of vocal cords determines the tone