Biology Journal 2/21/14 What is oxygenated blood? Where could we find it? What is deoxygenated blood? Where could we find it?

They increase the surface area of the lungs Have thin membranes They are moist They are full of capillaries What are alveoli? What could be some ways that they are adapted to do their job more efficiently? Biology Journal 2/24/14

What is inspiration? What parts of your body move to make it happen? What is expiration? What parts of your body move to make it happen? Biology Journal 2/25/14

Inspiration is breathing in. The diaphragm contracts, and the intercostal muscles move the ribs up and out. This creates a vacuum where air is sucked in. Expiration is breathing out. The diaphragm relaxes, and the intercostal muscles move the ribs down. This squishes the lungs, and air is expelled. Biology Journal 2/25/14 Air moves in and out of the lungs because of air pressure changes caused by creating an empty space in the lungs or squeezing that space.

6.4 Gas Exchange Assessment statement 6.4.1Distinguish between ventilation, gas exchange and cell respiration Explain the need for a ventilation system.  To maintain high concentration gradients in the alveoli Describe the features of alveoli that adapt them to gas exchange.  large total surface area  wall consisting of a single layer of flattened cells  film of moisture  dense network of capillaries Draw and label a diagram of the ventilation system, including:  Trachea  Lungs  Bronchi and bronchioles  Alveoli (draw the alveoli in an inset diagram at a higher magnification) 6.4.5Explain the mechanism of ventilation of the lungs in terms of volume and pressure changes caused by the internal and external intercostal muscles, the diaphragm and abdominal muscles.

Gas Exchange

The purpose of a ventilation system is to maintain high concentration gradients (of O 2 and CO 2 ) between the air and the blood.

Your lungs are filled with alveoli that are sacs that fill up with air. Capillaries surround the alveoli, so that gasses can diffuse to/from the blood

Oxygen isn’t the only thing that can diffuse through the lungs… What do you think smoking does to the alveoli?

Smoking is also terrible for your heart. Why is that?

Smoking constricts your blood vessels, raising your blood pressure. This makes your heart work harder, weakening it. Smaller arteries can also lead to blood clots: heart attacks and strokes.

All that, and cigarettes cause cancer, too.

How are alveoli adapted for gas exchange? They increase the surface area Have thin membranes They are moist They are full of capillaries

Passive transport through the membrane. The small, nonpolar gasses pass directly through the phospholipid membranes of the alveoli and the capillaries.

Awesome IB test question! How many membranes does O 2 have to pass through in order to go from the gas inside of a lung to the hemoglobin protein in a red blood cell? Five! Through 2 membranes of alveoli, 2 membranes of the capillary, and one membrane of the red blood cell.

Youtube videos: Title: ”Respiratory System”