the respiratory system chapter 17 section 1. key concepts what are the functions of the respiratory...
TRANSCRIPT
The Respiratory System
Chapter 17
Section 1
Key Concepts
What are the functions of the respiratory system?
What structures does air pass through as it travels to the lungs?
What happens during gas exchange and breathing?
Key Terms
Respiration Cilia
Pharynx Trachea
Bronchi Lungs
Alveoli Diaphragm
Larynx Vocal cords
Respiratory system functions
How long can without breathing?Body cells need oxygen and they get it
from the air you breathe.The respiratory system moves oxygen
from the outside environment into the body while removing carbon dioxide and water from the body
Taking in Oxygen
Oxygen is needed for the energy releasing chemical reactions that take place in your body Ex. A fire cannot burn without oxygen, cells
cannot burn enough fuel to keep you alive without oxygen
Respiration vs. breathing
Respiration is the process in which oxygen and glucose undergo a complex series of chemical reactions
Breathing is the movement of air into and out of the lungs
As a result of respiration cells release the energy that fuels growth and other cell processes
Removing Carbon Dioxide and Water
Respiratory system eliminates carbon dioxide and some of the water through your lungs
Respiratory, digestive, circulatory systems
Respiration could not take place without the digestive and circulatory system Respiratory system brings oxygen into your
lungs Digestive system absorbs glucose from the
food you eat Circulatory system carries both the oxygen and
the glucose to your cells
Path of air
Outside environment lungs passes through the following structures-nose, pharynx, trachea and bronchi
The Nose
Air enters the bodyMoves into spaces called nasal cavitiesSome of the cells lining the nasal cavities
produce mucusSticky material moistens the air and keeps
the lining from drying outMucus traps particles such as dust
(2)
Cilia are tiny hair like extensions that can move together in a sweeping motion
Cilia sweep the mucus into the throat where you swallow it
Stomach acid destroys the mucus along with everything trapped in it
Some particles can irritate the lining of your nose or throat, you sneeze and the particles shoot out of your nose into the air
The pharynx
Air enters the pharynx-throatPharynx is shared with the digestive
system-the nose and mouth connect to the pharynx
The trachea
From the pharynx air moves into the trachea or windpipe Run your fingers down the center of your neck-the
trachea feels like a tube with a series of ridges, the firm ridges are rings of cartilage that strengthen the trachea and keep it open
Like the nose the trachea is lined with cilia and mucus Cilia in the trachea sweep upward moving mucus
toward the pharynx where it is swallowed Tracheas cilia and mucus continue the cleaning and
moistening of the air that began in the nose
(2)
Normally only air not food enters the trachea
If food does enter, and block the opening and prevents air from getting to the lungs a person chokes
The epiglottis a small flap of tissue that folds over the trachea sealing off the trachea while you swallow
Bronchi and lungs
Air moves from the trachea to the bronchiLungs are the main organs of the
respiratory systemLeft bronchus leads into the left lung same
for the right side. Right bronchus leads to the right lung
Inside the lungs each bronchus divides into smaller and smaller tubes resembling the branches of a tree
(2)
The smallest tubes at the end of the structures look like bunches of grapes-alveoli-tiny sacs of lung tissue for the movement of gases between air and blood
Gas exchange
The walls of the aveoli and the capillaries are very thin allowing certain materials to easily pass through them
After air enters an alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood
Carbon dioxide and water pass from the blood into the alveoli
You lungs can absorb a large amount of oxygen because of the large surface area of the alveoli
The huge surface area of the alveoli enables the lungs to absorb a large amount of oxygen
How you breathe
How many times do you breath in an average day? 20,000-the rate at which you breath depends on
your body’s need for oxygen
Muscles for breathing
Breathing is controlled by muscles Picture
The lungs in the picture are surrounded by ribs, attached to them are the muscles, at the base is the diaphragm
The diaphragm is a large dome shaped muscle
Process of breathing
When you breathe your rib muscles and diaphragm expand or contract your chest-air flows in and out
Inhaling-the diaphragm contracts and moves downward
Exhaling-the rib muscles and diaphragm relax, reducing the size of the chest cavity-decrease in size squeezes air out of the lungs
Breathing and speaking
The air that moves out of your lungs as you breathe also helps you speak
The larynx is located in the top part of the trachea underneath the epiglottis