teeth tongue salivary glands pharynx epiglottis uvula
TRANSCRIPT
Nutritional Requirements of Animals
• Three nutrition needs – Chemical energy– Raw materials– Essential nutrients
• substances that animals cannot make for themselves from any raw materials and has to take it in its pre-made form
Intracellular vs. Extracellular Digestion
• Intracellular (inside cell)– Food vacuoles– Digestion with
lysosomes• Extracellular (outside)
– Hydrolysis– For bigger prey
Mouth
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Teeth
Tongue
Salivary Glands
Pharynx
Epiglottis
Uvula
• Teeth, tongue, and saliva
• Mastication: Chewing – Increases surface area exposed to
digestive juices
• Peristalsis: Contractions – Allows food particles to mix with
enzymes and gastric juices
Mechanical Disgestion
• Made of tissues varying in density and hardness
• 3 different types of teeth needed for digestion
Incisors
Canines
Molars
Teeth
http://wikapedia.com
• Extremely muscular and mobile
• Epithelial cells
• Located on the floor of the mouth
• Tasting, chewing and swallowing
Tongue
http://webcrawler.com
• Produce saliva in mouth – Mucin – Buffers preventing tooth decay– Antibacterial agents– Salivary amylase
• Acini
• Three pairs of salivary glands
Salivary Glands
http://3.bp.blogspot.com
• Short and broad muscular tube beginning at the back of the mouth
• From mouth and nose to esophagus and larynx
• Permits passage of swallowed solids and liquids into esophagus
• Divided into three parts Nasopharynx OropharynxLaryngopharynx
Pharynx
http://www.web-books.com
• Flap of tissue preventing food from entering the trachea
• Upward during breathing
• Horizontal when swallowing
• Food goes down the esophagus
Epiglottis
http://people.eku.edu
• Cone-shaped mass of tissue hanging from the soft palate
• Works to make sure food goes down the right tube while swallowing Blocks off airway to the nose
Uvula
http://www.goldbamboo.com
Esophagus • A muscular tube that passes food from pharynx to
the stomach • 25 cm long • Behind trachea and heart • Transport of liquids depends on how body is
positioned when swallowing
http://assets.aarp.org
• Begins in the mouth with salivary amylase
• Gastric fluid
• Pepsinogen pepsin peptides
• Hydrochloric acid- low pH, dissolves minerals, and kills bacteria
• Mucus protects stomach from the acid and pepsin
http://www.oralchelation.com/faq/images/stomach_diagram.jpg
Chemical Digestion
• 3-4 hours of stomach digestion• Chyme• Peristalsis forces chyme out of the
stomach• Pyloric sphincter regulates the flow of
chyme• Then it mixes with secretions form the
liver and pancreas in the small intestine
http://www.gesa.org.au/digestive-system/stomach.cfm
Formation of Chyme
• 21 ft long
• Duodenum, jejunum, and the ileum
• Continuation of chemical digestion of chyme
• Glands release enzymes that complete digestion
http://www.besthealth.com/besthealth/bodyguide/reftext/html/dige_sys_fin.html
http://www.gesa.org.au/digestive-system/small_intestine.cfm
Small Intestine
• Folds of intestine covered with villi• Absorption• The end products of digestion are transferred into the
circulatory system • Lacteals
http://www.belmarpharmacy.com/images/clip_image002.jpg
Small Intestine
• “Colon”• Peristalsis• Four major parts of the colon• Sigmoid colon leads into the rectum and anal canal• Feces• Recovering water• Harmless bacteria
http://www.google.com/imgres?imgurl=http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19220.jpg&imgrefurl=http://www.nlm.nih.gov/medlineplus/ency/imagepages/19220.htm&h=320&w=400&sz=22&tbnid=GtQVeA06-ND7RM:&tbnh=99&tbnw=124&prev=/images%3Fq%3Dlarge%2Bintestine&hl=en&usg=__KRfR924GR6x6tIMuCUvqiBZ78to=&ei=8HUkSu69LJ3Ktgebq5zdBg&sa=X&oi=image_result&resnum=1&ct=image
Large Intestine
• Right of the stomach and is the second largest organ in the body
• Products of digestion are transferred to the liver for further processing
• Produces bile
• Cells contain a number of enzymes that break down toxins or chemicals
• Stores glucose as glycogen, makes proteins and breaks down toxic substances
Liver
http://health.allrefer.com/health/biliary-atresia-bile-produced-in-the-liver.html
Picture:
Liver
• Digestive juice secreted by the liver and stored in the gallbladder aiding in digestion of fats
• Modified by addition of a watery bicarbonate as it flows through the bile duct
http://health.allrefer.com/health/sclerosing-cholangitis-bile-pathway.html http://health.allrefer.com/health/biliary-atresia-bile-produced-in-the-liver.html
Bile
• Bile is transferred to the gallbladder
• It is a sac-like organ that stores and concentrates bile
• Bile is released into the small intestine through the common bile duct when chyme is present
http://www.acm.uiuc.edu/sigbio/project/digestive/middle/gallbladder.html
Picture:
Gallbladder
• Lies behind the stomach and has two important functions
It produces sodium bicarbonate which neutralizes stomach acid
It also produces enzymes that break down macromolecules
• Pancreatic fluid enters the small intestine through the pancreatic duct
http://www.dwp.gov.uk/medical/med_conditions/pd/Picture:
Pancreas
Diseases of the Digestive System:
• Short Bowel Syndrome
• Stomach Cancer (Gastric Cancer)
Common Sicknesses/Diseases:
• Acid Reflex
• Indigestion
• Diarrhea
• Irritable Bowel Syndrome (IBS),
http://en.wikipedia.org/wiki/File:Adenocarcinoma_of_the_stomach.jpg
Respiration – Gas exchange
• Main idea– O2 (from the
respiratory medium) in and CO2 out
• Respiratory surface – the more area, the more diffusion of gases, the better the respiration
Advantages and Disadvantages of Water as a Respiratory Medium
• D– Low concentration
of oxygen– Lower diffusion rate
• A– Simplest kind of
diffusion
Gas exchange in the lungs
• http://www.youtube.com/watch?v=d69oc8XAIyQ
Positive and Negative Pressure Breathing
• Positive pressure- air pushed in• Negative pressure- air drawn in• Humans practice negative using manipulation
of diaphragm
Respiratory System of Mammals vs Birds
• Mammals use lungs & diaphragm manipulation
• Birds have system of air sacs that expand and contract to fill lungs
• Air moves in 1 direction, and is more efficiently exchanged
Lung Capacity Terms
• Tidal volume- Total volume of air inhaled and exhaled with each breath
• Vital Capacity- Maximum tidal volume during forced breathing
• Residual volume- air left in lungs when rest is forcefully exhaled
Breathing Control
• Two main regions- Pons, Medulla Oblongata• Negative feedback/ stretching of lungs• Detection of carbonic acid leads to deeper
breathing
Partial Pressure’s Role in Gas Exchange
• Partial Pressure- Amount of pressure exerted by a specific part of an atmosphere
• Same concept as solute diffusion; movement from high to low partial pressure
• Also applies to capillaries (diffusion into interstitial fluid)
Advantages of Respiratory Pigments
• O2 in solution with blood too inefficient; respiratory pigments compensate
• Hemocyanin- Blue, found in mollusks and arthropods• Hemoglobin- Red. 4 subunits with an iron atom in middle of
each. Can carry 4 O2 molecules
The Affinity of Hemoglobin for Oxygen
• Saturation increases as partial pressure increases
• Greater affinity when less oxygen is available, like in a muscle doing work
• Bohr shift- changein affinity for O2 dueto change in pH
Carbon Dioxide Transport
• 3 modes- Solution with plasma, transport by hemoglobin or *conversion to bicarbonate ions*
• CO2 becomes carbonic acid, then dissociates into bicarbonate ions and H+ ions
• Bicarbonate ions piggyback onto red blood cells/ convert back to CO2 in lungs
Diving Animal Adaptations
• More O2 stored in blood• Blood rerouted to vital areas• Myoglobin- stores 25% O2 in muscles• Fermentation operates muscles when O2 depleted
Works Cited
• Campbell, Neil, and Jane Reece. Biology. 6th. San Francisco: Pearson, 2002.
• Sharpe, Shirlie. "Omnivore, Hebivore, Carnivore, What's the Difference?." About.com: Freshwater Aquariums. n. page. Web. 2 May. 2012.
• "Mechanical and Chemical Digestion." hellolife. Digestive Health Support Group, 06 April 2010. 0. Web. 2 May 2012. <http://www.hellolife.net/digestive-health/b/mechanical-and-chemical-digestion/>.