Includes cellular respiration AND Gas Exchange Human Respiration Includes cellular respiration AND Gas Exchange

Human Respiratory System Nasal Cavity Pharynx Epiglottis Larynx Trachea Bronchi Bronchioles Alveoli Diaphragm

1. Nasal Cavity Air enters through the nostrils. The nasal cavity is lined with a ciliated mucus membrane This cleans, warms, moisturizes the air

2. Pharynx Place where the oral and nasal cavities meet

3. Epiglottis A flap of tissue which covers the opening of the trachea during swallowing

4. Larynx In the top of the trachea Also called the voice box It contains vocal chords which allows for speech Bigger in males; a deeper voice requires longer chords, and a bigger housing to keep them in

5. Trachea Called the windpipe Tube in which air travels from the pharynx to the lungs Lined with a ciliated mucus membrane Ringed with cartilage; keeps tube open during breathing

6. Bronchi Singular: Bronchus A branching of the trachea Lined with a mucus membrane and ringed with cartilage There are two of these in the body

7. Bronchioles A branching of the bronchi Lined with a mucus membrane Ends in alveoli

8. Alveoli Singular: Alveolus Lungs contain millions of these Grape-shaped structures The walls of these are thin and moist Surrounded by capillaries 1 cell layer thick Oxygen diffuses from alveoli into capillaries Carbon dioxide and water diffuse from capillaries and are exhaled

6-8. LUNG Each bronchus with it’s bronchioles and alveoli make up a lung

9. Diaphragm A muscle at the bottom of the chest cavity It changes the pressure in the chest, causes breathing

Figure 42.23ab The mammalian respiratory system

Figure 42.23cx1 Alveolar structure of mouse lung

Figure 42.23c Alveoli

Figure 42.23cx2 Alveolar structure of mouse lung

Gas Exchange Oxygen diffuses from alveolicapillaries It loosely bonds to hemoglobin, forming oxyhemoglobin The oxygen separates from the blood in the body tissues Carbon Dioxide and water diffuse from cells into capillaries Carbon dioxide is carried in the form of bicarbonate ions (HCO3-) In lungs, these wastes diffuse from the capillaries into alveoli

Breathing Air moves into and out of lungs Lungs contain no muscles, but are elastic, so how do you breathe? By pressure changes in the chest caused by: Changes in the diaphragm and intercostal muscles: muscles between ribs which causes the rib cage to get bigger and smaller

Inhalation Ribs push up and out The diaphragm moves down Makes the chest cavity bigger, which reduces pressure around the lungs Air rushes in from the outside to fill the lungs

Exhalation Ribs move in and down Diaphragm moves up These make the chest cavity smaller, increasing the pressure, air leaves the lungs

Breathing

Breathing Rate Controlled by medulla in brain Breathing center in brain senses CO2 levels in blood When CO2 is high, impulses are sent to diaphragm which increases breathing rate As CO2 levels drop, breathing slows This is called a negative feedback mechanism

Disorders of the Respiratory System Asthma: Allergic reaction where bronchial tubes narrow and make breathing difficult Bronchitis: Inflammation of bronchial tube linings. Swelling causes air passages to become narrowed and mucus filled. Coughing and difficulty breathing is a result Emphysema: Walls of the alveoli break down. This decreases surface area. Shortness of breath, difficulty in breathing, decreased lung capacity is a result

The manufacture of ATP from glucose RESPIRATION The manufacture of ATP from glucose

Adenosine Triphosphate(ATP) The only useable form of energy for living cells

Cellular Respiration A series of enzyme-controlled reactions in which the chemical bond energy released by the breakdown of glucose is transferred to the bonds of ATP. This happens in the mitochondria for aerobic cellular respiration It happens in the cytoplasm for anaerobic cellular respiration

ATPADP + P Conversions When ATP is hydrolyzed, Adenosine Diphosphate (ADP) and a phosphate (P) is produced, and ENERGY is released. This energy is used for the reactions of cell metabolism

Here’s the Reaction

Anaerobic Respiration Anaerobic: Without Air Also called fermentation Lactic Acid Fermentation: In bacteria and animal muscle cells: Glucose2 lactic acid + 2ATP Alcoholic Fermentation:In yeast: Glucose2 Alcohol + 2CO2 + 2ATP

Products of Fermentation Lactic Acid: Cheese Buttermilk Yogurt Dill pickles Alcoholic: Baking Wine/ Beer/ Liquor

Aerobic Respiration Happens WITH oxygen Here’s the Reaction: C6H12O6+6O26H2O+6CO2+36ATP How much more efficient is this than anaerobic respiration as far as ATP production is concerned? Why is this?

The Big Picture…… In the Mitochondria