Respiration Unit 1. What parts of the body are involved in respiration? 2. How do we regulate our breathing to maintain homeostasis? 3. How do we breathe, and how much air can our lungs hold? 4. What can go wrong with our respiratory system?

Start with what we know! 1.How does sugar get from a piece of pie to our muscle cells? 2.What gas is used to break down sugar in cellular respiration? 3.What gas is produced in cellular respiration? 4.What cells undergo cellular respiration? 5.How does gas get from this room to our muscle cells in our stomach? (4 stages of respiration – page 244)

Start with what we know! Open textbook to page 243 and let’s read the first paragraph together. With your neighbour – determine how this model works to fill the lungs (balloons). Then see this!Then see this Would it work if the system was not airtight? Can you match the parts of the balloon model to structures in our body? Which ones?

Respiratory Anatomy 1.Nasal Cavity Air conditioner: warms/cools, humidifies, and filters incoming air Location of olfactory sense organs

Increased surface area to exchange heat and sense odor chemicals. Tear glands supply moisture to incoming air

2. Pharynx (Throat) Muscular passageway lined with mucous membrane (for extra cleaning) Extends from nasal cavity to the larynx and esophagus

3. Larynx (“Adam’s Apple”) Cartilage, muscle, and ligament structure Contains the voice box Found between pharynx and trachea

For Your Information Only: Voice The vocal cords are two ligaments found in the larynx that vibrate as air is forced from the lungs to the pharynx. The length and tension of the cords change the pitch of the sound (men have larger larynx or “bigger drum” = lower pitch) Little inflammation causes lower-pitch Lots of inflammation will cause loss of voice

4. Trachea (“windpipe”) 2-3cm diameter and 10-12cm long Lined with ciliated mucous membrane to catch particles Reinforced with cartilage rings. These keep the trachea open all of the time so that air can come in easily

For your information - Tracheostomy Incision in trachea for temporary or permanent breathing passage Reasons involve injury, infections, birth defects, cancers, burns, obstructions Check this out

5. Bronchi Cartilage rings prevent them from collapsing One primary bronchus branches off of trachea to go to each lung Secondary bronchi transmit large volumes of air rapidly within the lungs Only function is to conduct air flow

6. Bronchioles NO cartilage, made up of smooth muscle Slow down the rate of air flow Approximately the thickness of a human hair During spasms, the bronchioles can constrict (blockage)

7. Alveoli Cluster of “grapes” covered by a capillary net and kept clean by cilia Kept moist to allow gases to dissolve, which is a necessary prerequisite for diffusion of oxygen and carbon dioxide in the lungs million alveoli in lungs, which increases surface area of the lungs 300x (25x greater than that of your skin) Take a look!

For Your Information – Respiratory Distress Syndrome Premature babies can die because the alveoli in their lungs will not inflate (called RDS). The alveoli are lacking surfactant ( a type of lipoprotein), a substance required to prevent the sides of the alveoli from sticking to each other when a person exhales.

8. Lungs Right is larger ( 3 lobes), left is smaller (2 lobes) Spongy (not muscular) tissue that is unable to inflate and stand up on their own Covered by visceral pleura. The fluid-filled pleural cavity lies between the visceral pleura and the parietal pleura, which lines the thoracic cavity.

8. Lungs (continued) This fluid attachment allows breathing to take place: the lungs stick to the inside of the chest, and as the chest moves up and out (and the diaphragm contracts), the lungs fill with air. The lungs ARE NOT ARE NOT ARE NOT empty bags like balloons. They are spongy. The ONLY STRUCTURE they may somewhat resemble a balloon is the alveoli. Know see if you can ID parts on this lung!this lung