This occurs during gaseous exchange as the blood in the capillaries surrounding the alveoli has a lower oxygen concentration of Oxygen than the air in the alveoli which has just been inhaled. Both alveoli and capillaries have walls which are only one cell thick and allow gases to diffuse across them.48 List all the muscles used in respiration. Which ones are used in quiet breathing and which ones are used in forced breathing only? Which ones are for expiration and which ones for inspiration?Diaphragm- forced breathing both inspiration and expirationExternal intercostals- forced breathing inspirationPectoralis minor- forced breathing, inspirationRectus abdominus - quiet breathingInternal and external oblique- quiet breathingTransverse abdominus- quiet breathingInternal intercostals-quiet breathing
49 What is the role of compliance, resistance (properties of lungs and chest walls), water surface tension and surfactant in breathing?Compliance is the ability of lungs and pleural cavity to expand and contract based on changes in pressure.Airway resistance is the opposition to flow caused by the forces of frictionSurfactant is a lipoprotein molecule that reduces the force of surface tension from water molecules on the lung tissue.50 What is the role of hemoglobin in gas transport?Hemoglobin is made up of four symmetrical subunits and four heme groups. Iron associated with the heme binds oxygen. It is the iron in hemoglobin that gives blood its red color.51 How is carbon dioxide transported in the blood?carbon dioxideis transported as bicarbonate. As blood flows through the tissues, carbon dioxidediffuses into red bloodcells, where it is converted into bicarbonateDigestive system and metabolism52 Name the 4 layers of a typical digestive organ, from inside to outside. 1. Mucosa 2. Submucosa 3. Muscularis 4. Serosa 53 Which type of tissue is each one made of? Mucosa- epithelium Submucosa- connective tissues Muscularis- smooth muscle Serosa- epithelium 54 What is the structure of peritoneum? a membrane made up of two layers. One layer lines the cavity and the other layer lines the organs. 55 List the regions of GI tract in proper order from mouth to anus. Mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, and anus 56 Explain the functions of each part - specific digestive processes (chemical or mechanical digestion), what is digested and absorbed in each. Chemical digestion- involves breaking down the food into simpler nutrients that can be used by the cells Mechanical digestion- involves physically breaking the food into smaller pieces. 57 List the accessory structures of digestive system (not the GI tract - the tube!), and explain briefly the function of each.
Teeth- grind and chew food Tongue- vital for chewing and swallowing Salivary glands- secrete saliva to moisten food Liver- regulates the composition of blood Gallbladder- reservoir for bile Pancreas- secretes insulin to lower blood glucose levels 58 List the digestive enzymes secreted in each region of GI tract, indicate where they come from and what kind of molecule they digest.