TEST 1 MATERIAL PDF

The Endocrine System Wednesday, October 23, 2024 10:25 PM / o o o – ▪ – o o ▪...

The Endocrine System Wednesday, October 23, 2024 10:25 PM / o o o – ▪ – o o ▪ ▪ o o – o o ▪ – o TEST 1 MATERIAL Page 1  – o o – – – – / – – –  → → o ▪ … ▪ … – – – – TEST 1 MATERIAL Page 2  – / / o – – – … TEST 1 MATERIAL Page 3  – o TEST 1 MATERIAL Page 4  – – – … o – ▪ / ▪ o – ▪ o o o ▪ ▪ o ▪ o ▪ o o o TEST 1 MATERIAL Page 5  The Cardiovascular System: Blood Wednesday, October 23, 2024 10:26 PM – – ▪ – ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ TEST 1 MATERIAL Page 6  ▪ o o o o o ▪ o o o ▪ – ▪ – ▪ – … o o / ▪ – o o ▪ – o o ▪ ▪ – TEST 1 MATERIAL Page 7  o ▪ o o ▪ – o ▪ ▪ ▪ o ▪ o o o o o ▪ o o o o o o ▪ ▪ ▪ ▪ ▪ TEST 1 MATERIAL Page 8  ▪ o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ ▪ o ▪ o o o ▪ ▪ TEST 1 MATERIAL Page 9  o – o ▪ o … o o o o ▪ ▪ o ▪ ▪ o ▪ ▪ TEST 1 MATERIAL Page 10  ▪ o ▪ / – o o ▪ ▪ o ▪ o ▪ ▪ ▪ ▪ o – ▪ o ▪ ▪ TEST 1 MATERIAL Page 11  o o o o o o ▪ o o ▪ o ▪ / o ▪ o TEST 1 MATERIAL Page 12  ▪ o TEST 1 MATERIAL Page 13  The Cardiovascular System: The Heart Wednesday, October 23, 2024 10:26 PM o o o o o o – o ▪ ▪ o ▪ o ▪ o ▪ o ▪ o o ▪ ▪ o ▪ TEST 1 MATERIAL Page 14  ▪ ▪ o ▪ o ▪ ▪ o o ▪ o ▪ ▪ o o ▪ TEST 1 MATERIAL Page 15  o o ▪ o ▪ o o o ▪ … o ▪ ▪ ▪ o o o o TEST 1 MATERIAL Page 16  o o ▪ o – o – ▪ o – ▪ o o o o o o o o o ▪ o TEST 1 MATERIAL Page 17  o o ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ o o o o ▪ ▪ o o o o TEST 1 MATERIAL Page 18  o ▪ ▪ ▪ ▪ o ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o o ▪ TEST 1 MATERIAL Page 19  – o o … o ▪ ▪ TEST 1 MATERIAL Page 20  ▪ o ▪ ▪ ▪ o ▪ ▪ o o o o o o o TEST 1 MATERIAL Page 21  o o o o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ o ▪ ▪ o o o ▪ – ▪ – / TEST 1 MATERIAL Page 22  / o o o ▪ o – o o ▪ o o ▪ o ▪ o o o / o ▪ o ▪ TEST 1 MATERIAL Page 23  o ▪ o ▪ o ▪ – o o o o ▪ o ▪ o ▪ ▪ o ▪ ▪ o o o – TEST 1 MATERIAL Page 24  o o ▪ ▪ ▪ ▪ o … o o ▪ ▪ ▪ – o o o – o – o – o ▪ o o ▪ ▪ ▪ ▪ TEST 1 MATERIAL Page 25  The Cardiovascular System: Blood Vessels Wednesday, October 23, 2024 10:25 PM o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ o ▪ o o o o o o o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ ▪ o ▪ ▪ TEST 2 MATERIAL Page 26  ▪ ▪ o ▪ o ▪ / o o ▪ ▪ o o o o o o o ▪ o ▪ / o ▪ o ▪ TEST 2 MATERIAL Page 27  o ▪ ▪ o ▪ o o o o o ▪ o o o o ▪ o o ▪ ▪ o ▪ o o ▪ ▪ o ▪ ▪ ▪ o ▪ o TEST 2 MATERIAL Page 28  ▪ o ▪ o ▪ ▪ o o ▪ o ▪ o – ▪ ▪ ▪ o ▪ o ▪ o o ▪ o o ▪ – TEST 2 MATERIAL Page 29 ▪ – ▪ ▪ o ▪ ▪ o o ▪ ▪ ▪ o o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ o o o o ▪ TEST 2 MATERIAL Page 30  o ▪ ▪ ▪ ▪ ▪ o ▪ ▪ o o ▪ o ▪ o ▪ – / – ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ o o ▪ ▪ o o ▪ ▪ o o ▪ o ▪ o ▪ o TEST 2 MATERIAL Page 31  ▪ o ▪ o o ▪ o ▪ o o o o ▪ ▪ o ▪ o o ▪ ▪ o o ▪ ▪ o o ▪ ▪ o o TEST 2 MATERIAL Page 32  ▪ ▪ o ▪ … o ▪ ▪ o ▪ o ▪ ▪ o o o o o ▪ o ▪ o ▪ o o o ▪ ▪ ▪ o o ▪ ▪ o ▪ ▪ o ▪ TEST 2 MATERIAL Page 33  ▪ o o o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ ▪ o o o ▪ / ▪ ▪ ▪ o ▪ / ▪ o ▪ TEST 2 MATERIAL Page 34  The Lymphatic System/Immunity Wednesday, October 23, 2024 10:30 PM o o o ▪ ▪ ▪ o o o o o ▪ o o ▪ o ▪ ▪ o ▪ o o ▪ ▪ ▪ TEST 2 MATERIAL Page 35  ▪ o o ▪ ▪ o ▪ ▪ o ▪ o o o ▪ o o o ▪ o ▪ ▪ ▪ ▪ ▪ o ▪ o ▪ o ▪ ▪ o ▪ TEST 2 MATERIAL Page 36  ▪ o ▪ o ▪ o o ▪ o o ▪ o o ▪ ▪ o o o o o TEST 2 MATERIAL Page 37  ▪ ▪ ▪ o o o o ▪ o o ▪ o o ▪ ▪ o o o ▪ TEST 2 MATERIAL Page 38  o ▪ o ▪ o ▪ ▪ o ▪ o ▪ ▪ … o o ▪ … … – o ▪ ▪ o ▪ – ▪ – ▪ o o o o TEST 2 MATERIAL Page 39  ▪ o ▪ ▪ o ▪ ▪ ▪ o ▪ ▪ ▪ ▪ – ▪ o ▪ o o ▪ o o ▪ TEST 2 MATERIAL Page 40  ▪ ▪ ▪ ▪ – o – – – o – ▪ o ▪ o ▪ o ▪ o ▪ o ▪ ▪ ▪ o o ▪ ▪ ▪ o o TEST 2 MATERIAL Page 41  ▪ o ▪ o o o o o o o o ▪ ▪ o o o o o – o ▪ ▪ … ▪ ▪ ▪ o TEST 2 MATERIAL Page 42  ▪ ▪ – ▪ o ▪ o TEST 2 MATERIAL Page 43  The Respiratory System Wednesday, October 23, 2024 10:31 PM o ▪ o o o ▪ o ▪ … ▪ ▪ o o o o ▪ ▪ ▪ ▪ o ▪ ▪ ▪ ▪ o ▪ ▪ TEST 2 MATERIAL Page 44  o ▪ ▪ o ▪ ▪ ▪ – o … ▪ – – ▪ – … o ▪ o ▪ – ▪ – ▪ – o ▪ o ▪ – ▪ – … o o o TEST 2 MATERIAL Page 45  o o – ▪ ▪ – o o … o – o ▪ o o ▪ o o o ▪ o ▪ o o ▪ o TEST 2 MATERIAL Page 46  o o – ▪ o – ▪ o o o ▪ ▪ o o ▪ ▪ o / o o o o ▪ o o o o ▪ ▪ o o o TEST 2 MATERIAL Page 47  o o o o o o ▪ ▪ ▪ o ▪ o ▪ o ▪ o – o ▪ ▪ … o ▪ o ▪ ▪ o … o o TEST 2 MATERIAL Page 48  ▪ ▪ o o o o o o o o o o ▪ ▪ o o o o ▪ ▪ o ▪ ▪ o TEST 2 MATERIAL Page 49  o o ▪ ▪ ▪ o ▪ ▪ o o o o ▪ o o o o ▪ ▪ ▪ ▪ o ▪ ▪ o ▪ – ▪ – o – o ▪ o ▪ TEST 2 MATERIAL Page 50  o o ▪ o o ▪ o o / o ▪ o o o ▪ o – ▪ o o ▪ ▪ ▪ ▪ o o TEST 2 MATERIAL Page 51  ▪ ▪ ▪ o – ▪ ▪ … o ▪ ▪ o o o o o o o TEST 2 MATERIAL Page 52 The Digestive System Wednesday, October 23, 2024 10:25 PM PRIMARY ORGANS/STRUCTURES OF THE GI TRACT Organization of the Digestive System Mouth (Oral cavity) Esophagus ○ Divided into 2 subgroups: ○ Mouth/oral cavity is formed by the: cheeks, hard & soft palate, lips, and tongue ○ Esophagus: long tube that connects the pharynx to the stomach Absorption… ▪ The GI tract (aka alimentary canal) ○ Vestibule of the mouth is the space between the cheek and lips (EXternal boundary) and gums ○ Layer linings: ○ Takes about 4 - 6 hrs □ This is the MAIN part of the digestive system and is, essentially, a long tube from and teeth (INternal boundary) … aka kinda where the tongue is lol ▪ Mucosa: made of stratified squamous non-keratinized epithelium ○ Most nutrients are absorbed via intestinal mucosa the mouth to the anus ○ Oral cavity proper is the space that extends from the innermost (gums and teeth) to outermost □ This epithelium's main function is PROTECTION ○ Most water in the GI tract (incl drinking water & water absorbed by accessory □ INCLUDES: mouth, pharynx, esophagus, stomach, small & large intestines, and boundary (the fauces) □ SSNKE. The mucosa has a SSN(A)KE, PROTECT YOURSELF! (girl pls glands) will be absorbed in the small intestine anus ▪ Fauces = opening that leads to the pharynx & larynx im trying to remember) ○ Peristalsis & segmentation are the 2 processes that propel food through the ▪ The accessory structures ○ Lip and cheeks: keep food in the mouth ▪ Submucosa: contains mucus-secreting glands that lubricate the esophageal small intestine □ Glands, organs, and other things that help the GI tract function in chemical & ○ Tongue: muscular organ that takes up most of the floor of the mouth. It's main function is to lining ▪ These movements are coordinated by the enteric nervous system + mechanical digestion of food move food around during mastication (CHEWING), mix it with saliva, and shape it into the ▪ Muscularis: made of longitudinal & circular smooth muscle layers that allow hormones that respond to the presence of chyme w/in the small intestine □ INCLUDES: teeth, tongue, salivary glands, pancreas, liver, and gallbladder bolus to be swallowed movement/propulsion of food Digestion as a process has SIX steps: ▪ Linguinal papillae (aka taste buds) detect food flavor □ Explained more in depth under FIRST SECTION ○ Ingestion (aka eating) □ HAS 4 PARTS: frenulum (tip), body (main part), root, and apex ▪ Adventitia: outermost connective tissue layer ○ Secretion (release by cells in the walls of the GI tract & accessory organs of water, acid, ○ The uppermost part of the esophagus is protected by the upper esophageal The Large Intestine (aka Colon) buffers, and enzymes into the lumen of the tract) sphincter and the lowermost part of the esophagus is protected by the lower ○ Shorter than the small intestine, but is larger in diameter ○ Mixing & propulsion (result of contraction & relaxion of smooth muscle in the GI tract esophageal sphincter ○ Colon is made of haustrae (pouches that increase the surface area of the walls) ▪ 6 MAJOR sphincters in the digestive system (NEED TO KNOW) colon to max water & electrolyte absorption) ○ Digestion (proper breakdown of large food molecules --> simple molecules) ○ First part of the colon is the cecum -- this is connected to the ileum (the final ▪ INCLUDES mechanical & chemical digestion segment) of the small intestine □ Mechanical digestion: movements of the GI tract that mix, soften, and liquefy ○ These segments are separated by the ileocecal sphincter the food. This begins in the MOUTH. ○ Vermiform appendix is attached to the cecum and may function in colic defense, but □ Chemical digestion: a series of enzymatic rxns that break down the the removal of this (appendectomy) does not have any serious impact on the kidney macromolecules in food to smaller molecules. This begins in the MOUTH for ○ Regions of the colon (L. intestine, pictured to the Right): carbohydrates, and the STOMACH for proteins. ○ Cecum ○ Absorption (passage of nutrients made from digestion from the GI tract lumen into ○ Ascending colon blood/lymph) ○ Transverse colon ○ Defecation (release of solid waste made by digestion from the rectum) ○ Palate: roof of the mouth, is subdivided into the hard & soft palate ○ Descending colon 4 basic layers of the GI tract (pictured below) from INNERMOST --> OUTERMOST are: ○ Uvula: extension of the soft palate. It contributes to modulation of sound and STOPS entry of ○ Sigmoid colon ○ Mucosa (epithelia) food into the nasal cavity when swallowing (so you don’t shoot food out of your nose) ○ Rectum ▪ Lines the GI tract lumen (innermost layer!) Saliva and Salivary Glands ○ Anal canal ▪ Has stratified cells (protection), simple columnar cells (secretion & absorption), ○ Three major pairs of salivary glands ○ Anus mucus secreting cells (protection & lubrication), and enteroendocrine cells ▪ Parotid ○ Know Colon Histology (release hormones involved in digestion) □ Located below the ear & masseters ○ Functions: ▪ Lamina propria here anchors the mucosa and provides a framework for blood & □ During buccal fat (cheek) removal, there is a risk of damaging the parotid duct □ Upper esophageal sphincter ○ Absorption of remaining water in chyme lymph vessels, and nerves because it is located in the cheek. If this gland was damaged, we would have Pharynx --> Esophagus ○ Production & storage of feces ▪ MALT (mucosa-associated lymph tissue) provides immune defense difficulty producing saliva, which would lead to dry mouth, bad breath, and other ○ Submucosa (connective tissue) □ Lower esophageal sphincter ○ This is the longest part of digestion (12 hrs) health complications. Esophagus --> Stomach ▪ Holds a large number of GLANDS, BLOOD VESSELS, NERVES, AND LYMPH ▪ Submandibular (aka submaxillary) ▪ Peristaltic waves from the ileum prompt the ileocecal valve to relax TISSUE □ Pyloric sphincter ▪ Chyme enters the large intestine (the colon) at the cecum □ Located under the lower edge of the mandible (jaw) ○ Muscularis (muscle tissue) Stomach --> Small intestine ▪ The ileocecal valve closes ▪ Sublinguinal ▪ Made of AT LEAST TWO layers □ Ileocecal valve/sphincter ▪ Colic muscle moves to push the chyme alone; colic muscle has 3 types □ Located under the tongue in the floor of the mouth □ Innermost = circular layer --> Small intestine (ileum) --> Large intestine (cecum) of movement: □ Outermost = longitudinal layer --> □ Internal anal sphincter □ Minor peristaltic waves: slow & sluggish □ NOTE: The stomach has THREE layers! □ External anal sphincter (under voluntary control!) □ Haustral churning: segmented contractions that mix the chyme to ○ Be able to recognize the esophageal layers on histogram! further enhance absorption ▪ Both layers work together to contract rhythmically during peristalsis to mix, crush, and move food through the GI tract [ attach picture here ] □ Mass peristalsis: large movements that occur in intervals and is Deglutition (aka swallowing) typically associated w/ meals. Is triggered by the presence of food ▪ Is a HIGHLY vascularized tract (as most muscle tissue is!) and holds the myenteric ○ This is the passing of food from the mouth to the pharynx, then the esophagus (the bolus at that point) in the stomach. plexus (this is a network of nerves that the sympathetic & parasympathetic nervous ○ Has THREE phases (in photo below): ○ Feces formation & Defecation Reflex system use… so it's also highly innervated) ▪ Animation showing movement through the GI tract ▪ Buccal (voluntary) ○ Chyme goes from liquid --> firm feces ○ Serosa (connective tissue) □ This takes place in the mouth!!! This is when the tongue is pushing the ○ Vitamins, like vitamin K & some B vitamins, are produced w/ the help of ▪ AKA the adventitia bolus towards the back of the mouth, into the oropharynx (middle layer of bacterial and absorbed w/ water and electrolytes ▪ MADE OF 2 LAYERS (as most serous membranes are lol…) the pharynx) ○ Feces will then be stored in the rectum ▪ These glands are ALL EXOCRINE and produce saliva that is delivered to the oral cavity □ Inner CONNECTIVE tissue layer made of AREOLAR connective tissue ▪ Pharyngeal (involuntary) ○ Wait… so how does defecation happen? via ducts Covers the other layers & leads blood vessels and nerves into them ○ Saliva is a watery secretion from the before mentioned salivary glands □ Starts when the presence of food in the oropharynx triggers the swallowing ▪ Pressure will be exerted on the rectum as feces builds up. At this point, reflex the internal anal sphincter, which is 1 of 2 sphincters that separates the □ Outer EPITHELIAL layer that attaches the GI tract to the peritoneum ▪ Functions include: Larynx is lifted, which causes the epiglottis to close rectum from the outside, will relax and let feces out. □ Moistening and lubricating materials in the mouth Uvula stops food from entering the nasal cavity via the nasopharynx □ The internal anal sphincter is made of smooth muscle, thus its □ Dissolving chemicals that stimulate taste buds & provide sensory info Pharyngeal muscles will continue to push the bolus down to the control is INVOLUNTARY. □ Initiate digestion of carbohydrates by salivary amylase esophagus ▪ The feces will then build pressure on the external anal sphincter, which CHEMICAL DIGESTION OF CARBOHYDRATES STARTS IN THE MOUTH ▪ Esophageal (involuntary) causes the feeling of needing the defecate □ Starts when the pharynx is lifted, causing the upper esophageal sphincter □ The external anal sphincter is made of skeletal muscle, thus its to relax (will allow food the bolus to pass through) control is VOLUNTARY. Pharynx □ Bolus enters the esophagus and the layers here will contract to propel it to ▪ To finally defecate, you will decide to relax the external anal sphincter, ○ Pharynx is a funnel-shaped tube that links the nasal & oral cavities and the larynx the stomach (aka peristalsis!) which will trigger the rectal muscles to contract and eject the feces. ○ Is subdivided into the: nasopharynx, oropharynx, and laryngopharynx. Only the nasopharynx is Peristalsis goes on until the bolus reaches the lower esophageal NOT involved in digestion, it is a passage way for air ONLY. sphincter, which causes it to relax, which allows the bolus to enter the stomach The Small Intestine Stomach □ Phase ends when the upper esophageal constricts, closing the ○ Plays a key role in chemical + mechanical digestion & absorption of nutrients ○ Major functions of the Stomach esophagus again, and the larynx & epiglottis return to their original ○ 90% of absorption occurs here! positions ○ Has 3 parts: ▪ Storage of ingested food ▪ Mechanical breakdown of ingested food ○ Duodenum ▪ Disruption of chemical bonds in food by acid & enzymes ▪ Is the segment closest to the stomach ▪ Production of intrinsic factor ▪ Acts as the "mixing bowl" that takes chyme from the stomach, as well as □ Intrinsic factor is a glycoprotein required for absorption of vitamin B12 in the small secretions from the pancreas (pancreatic juice) & liver (bile) intestine ▪ Main functions: receive chyme, neutralize acids before they can damage the NOTE: Vitamin B12 is required (with vitamin B6) for production of small intestine HEMOGLOBIN!! ○ Jejunum ○ Shaped like an expanded "J" ▪ Middle segment of the small intestine (right after the duodenum) ▪ Smaller curve is the medial surface ▪ Main functions: chemical digestion & nutrient absorption The structure of the Peritoneum ▪ Larger curve is the lateral surface □ Digestion & absorption in the entire small intestine occur MOSTLY here ○ Peritoneum is the LARGEST serous membrane in the body ○ Regions (in the picture below) ○ Ileum ▪ Parietal peritoneum = outermost layer and lines the walls of the abdominal cavity ▪ Cardia ▪ Final, and longest, segment of the small intestine ▪ Visceral peritoneum = innermost layer and covers some organs & makes up their ▪ Fundus ▪ Ends at the ileocecal valve (small intestine --> large intestine) ▪ Body ○ Layers respective serous tissue ▪ The space between these layers is the peritoneal cavity, and is filled with serous fluid ▪ Pylorus ○ Has only two layers of muscle, unlike the stomach that has 3 □ Just like in the lungs and the heart!!! Stomach Small intestine ○ KNOW: the regions of the peritoneum (below) Gastric pits Intestine crypts ○ Rugae (folds in the Circular folds organ, making it look rough) ○ Is also lined with villi (further increasing absorption ○ Intestinal mucosal layer ▪ Note that during the pharyngeal and esophageal phase, we are unable to ○ Circular folds/plicae circularis are folds of the mucosa & submucosa meant to breathe because the closing of the epiglottis during the swallowing reflex increase the absorption surface prevents not only food from going down our larynx, but air as well! ○ Villi are finger-like projections of the mucosa, which are lined w/ mucous secreting ○ Problems w/ swallowing goblet cells (secrete mucus for protection) & simple columnar absorptive cells ▪ Swallowing too fast means the epiglottis may not have enough time to close, so called enterocytes food may enter the air passage and impair breathing. Coughing is the first reflex ▪ Villi also increase surface area for absorption to remove the obstruction, but more serious methods may be required to ○ Mucosal layer in each villi holds blood capillaries & a lymphatic capillary (lacteal) achieve this such as backslaps, the Hemliech ○ Intestinal juice is secreted by epithelial cells of the crypts of Lieberkhun (a ○ Stomach, in general, is a very muscular layer. Its muscularis layer has 3 layers (which is unlike duodenal gland!!!) at the base of each villus. This juice holds important enzymes ▪ Swallowing a large or partially masticated (chewed) amount of food can make other GI tract organs!!) known as brush border enzymes that complete digestion peristalsis painful and slow ▪ Longitudinal (outermost) ○ Brush Border Enzymes ▪ When the lower esophageal sphincter fails to close, stomach acids may enter ▪ Circular (middle) the esophagus which causes heartburn ○ Aminopeptidase, dipeptidase - split dipeptides (polypeptide) into amino acids ▪ REGIONS ARE: ▪ Oblique (innermost) (monopeptide) □ Mesentery: located the back of the abdominal wall where the small intestine ▪ These 3 layers work together to allow the stomach to contract w/ enough force to mix the ○ Sucrase, lactase, maltase - breaks disaccharides into monosaccharides attaches food w/ gastric juice… which allows further mechanical breakdown of the bolus AND Double sheets of the peritoneal membrane that suspends parts of the ▪ Sucrase targets Sucrose liquefies it! These layers also make it easier to eject the liquefied bolus (now chyme) into ▪ Lactase targets Lactose digestive tract in the peritoneal cavity by using sheets of the serous the small intestine membrane that connect the 2 peritoneum layers together ▪ Maltase targets Maltose ○ Gastric Mucosa (stomach lining) ○ Enterokinase - activates trypsinogen to make trypsin. Trypsin then activates □ Mesocolon ▪ Is made of simple columnar epithelial cells zymogens to carry out digestion □ Falciform ligament □ Main function of these cells is: absorption, excretion, and secretion ○ Nucleosidase, phosphatase - remove phosphate group & separates pentose sugar □ Lesser & Greater omentum Stomach Cells Stay Simple for Secretion & Absorption from the nitrogenous base (literally breaking apart nucleic acids) Greater omentum is full of fat and the usual target of liposuction ◊ Simple = simple columnar cells, Secretion & absorption = their primary ○ Absorption of Nutrients in the Small Intestine ◊ This layer also extends inferiorly (behind) between the body wall & function ○ Monosaccharides, amino acids, di- and tripeptides, and short chain fatty acids front surface of the small intestine ▪ Ridges of the gastric mucosa are called rugae and give the stomach its rough appearance move through mucosa cells to blood Lesser omentum stabilizes part of the stomach □ Functions to increase the mechanical properties of the stomach and allow it to ▪ These substances being moved are the nutrients the body wants to keep ▪ NOTE: these regions are ALL part of the VISCERAL peritoneum, as mentioned contract & return to its original shape ○ Long fatty acids, cholesterol, and monoglycerides (form of fat) are moved through before!!! ▪ Infoldings of the mucosa are gastric pits (shallow depressions on the gastric surface) mucosa cells to the lymph, where they will be discarded Functions of the Peritoneum ○ Gastric Glands ○ Vitamins & minerals are absorbed w/ other nutrients. ○ Organs on the posterior abdominal wall are RETROperitoneal. These organs include: ▪ We have 4 types: ▪ Lipid soluble vitamins are taken with lipids ▪ Aorta, inferior vena cava, kidneys, adrenal gland, pancreas, DUODENUM, and the □ Chief cells -- Exocrine ▪ Water soluble vitamins are taken via diffusion ascending & descending colons Secrete inactive ver of enzymes pepsinogen & gastric lipase (type of zymogen) ○ Mechanisms of absorption depend largely on what is being absorped ○ Organs within the folds of the peritoneum are INTRAperitoneal. These organs include: ◊ Pepsinogen is an enzyme that breaks down PROTEIN, so DIGESTION OF ▪ Mechanisms include: simple diffusion, facilitated diffusion, secondary/primary ▪ Stomach, small intestine (ONLY THE JEJUNUM & ILEUM), transverse colon, liver, & PROTEIN STARTS IN THE STOMACH active transport, exocytosis, endocytosis gallbladder □ Parietal cells -- Exocrine Secrete HCl (which is what makes gastric juice so acidic) and intrinsic factor (already covered) □ Mucous neck cells -- Exocrine Secretes mucus that protects the mucosa from the super acidic gastric juice □ G cells -- Endocrine Secretes gastrin ○ Pepsin + HCl + Mucus = gastric juice ▪ Pepsin comes from CHIEF CELLS ▪ HCl comes from PARIETAL CELLS ▪ Mucus comes from MUCOUS NECK CELLS ○ 2 types of digestion take place in the stomach ▪ Mechanical digestion: peristalsis in the stomach causes the bolus & gastric juice to mix, which turns the bolus into chyme ▪ Chemical digestion: of proteins by pepsin, as well as breakdown of SOME fats by lipases here ▪ Intrinsic factor, which is produced by parietal cells, will be absorbed later in the small intestine ▪ NOTE: The products made here are NOT absorbed by the stomach lining, but some drugs (ex: aspirin & alcohol) may pass through the stomach lining □ This may lead to the formation of an ulcer, as the acidic gastric juice (sometimes, not always) burns through the stomach lining □ But the stomach, in general, does NOT absorb food… that is the intestine's job (S. & L. Intestines, we fucking love you…) ○ Gastric Secretion has 3 Phases (explained further HERE) ▪ Cephalic phase -- primarily neural □ Gastric juice secretion is triggered by the taste, smell, thought, and/or presence of food in the mouth ▪ Gastric phase □ Presence of food in the stomach stretches the stomach lining (gastric mucosa) and cause gastric juice to continue to be secreted ▪ Intestinal phase □ The stomach empties gastric juice + chyme into the duodenum of the small intestine. At this point, the presence of very acidic chyme (pH lacteals □ Lacteals: special lymphoid capillaries in villi ▪ Very low-density lipoproteins (VLDLs) □ Carries triglycerides made in the liver --> adipose tissue □ Are converted to LDLs □ Are 10% protein ▪ Low-density lipoproteins (LDLs) □ Transport cholesterol --> body cells by circulating it through blood □ Considered "bad cholesterol", BUT IS NOT ACTUALLY CHOLESTEROL. IT IS A CHOLESTEROL CARRIER. This is because they can deposit cholesterol around blood vessels when in high amounts □ Are 25% protein ▪ High-density lipoproteins (HDLs) □ Remove excess cholesterol from cells and sends it to the liver for elimination □ Considered "good cholesterol" □ Are 40% protein NOTE: Fat carries a LOT of energy. ○ When broken down via lipolysis, 1 triglyceride provides 1 glycerol head and 3 fatty acids (the tails). These fatty acids can then be metabolized and can produce up to 30 ATP via beta-oxidation for each fatty acid. ▪ This process is more complex, though, so the body prefers to use glucose for quick, short-term energy needs while fat is preferred as a long-term energy storage. Lipogenesis ○ Lipid synthesis that uses almost any organic structure ▪ Lipids, amino acids, and carbohydrates can all be converted to acetyl -CoA to enter the citric acid cycle ○ Essential fatty acids cannot be produced by the body and must be consumed ▪ Include: □ Linoleic acid □ Linolenic acid Lipolysis & Other Lipids Functions Adipose triglycerides are broken down and released as free fatty acids ○ Are then taken up by cells and broken down via beta-oxidation into acetyl-coA ▪ Acetyl-CoA can then enter the citric acid cycle or are converted to ketone bodies Other lipids are used as structural molecules or to make essential molecules, such as: ○ Phospholipids (in plasma membrane), lipoproteins (cholesterol transport), thromboplastin (in blood clots), cholesterol (used to make bile salts & steroid hormones) Protein Metabolism During digestion, proteins are broken down into amino acids that are absorbed by villa capillaries ○ Amino acids are sent to the liver via the hepatic portal system ▪ Here, they enter general circulation to reach body cells via active transport □ Amino acids are used to create proteins or as an energy source □ They are NOT stored in the body Amino Acids Catabolism Amino acids MUST be converted to other substances in order to enter Krebs cycle for oxidation ○ They can be: ▪ Deaminated □ Removal of an amino group, which creates nitrogenous wastes like urea ▪ Decarboxylated ▪ Dehydrogenated Essential Amino Acids Molecules that we can NOT make ourselves OR are made in low amounts Humans can NOT make: ○ Leucine ○ Isoleucine ○ Lysine ○ Methionine ○ Phenylalanine ○ Threonine ○ Tryptophane ○ Valine Humans make these in small amounts ○ Arginine ○ Histidine Metabolic Adaptations Absorptive state ○ Period immediately after eating when nutrients are absorbed via the intestinal wall into circulatory & lymphatic systems ○ Occurs ~4 hours after each meal Hormone Effect on General Peripheral Tissues Selective Effects on Target Tissues Insulin Increased glucose uptake & use Liver: Glycogenesis Adipose tissue: lipogenesis Skeletal muscle: glycogenesis ○ Insulin & Growth Increased amino acid uptake & protein Skeletal muscle: fatty acid catabolism Hormone synthesis Androgens, Estrogens Increased amino acid use for protein Skeletal muscle: muscle hypertrophy (esp w/ synthesis androgens) TEST 4 MATERIAL Page 61  Adipose tissue: lipogenesis Skeletal muscle: glycogenesis ○ Insulin & Growth Increased amino acid uptake & protein Skeletal muscle: fatty acid catabolism Hormone synthesis Androgens, Estrogens Increased amino acid use for protein Skeletal muscle: muscle hypertrophy (esp w/ synthesis androgens) Postabsorptive state ○ Occurs in the late morning, afternoon, or night after the absorptive state ends ○ Blood glucose levels are maintained by conversion of other molecules --> glucose Hormone Effect on General Peripheral Tissues Selective Effects on Target Tissues Glucagon -- Liver: glycogenolysis Epinephrine -- Liver: glycogenolysis Adipose tissue: lipolysis Liver: glycogenolysis ○ Adipose tissue: lipolysis, Glucocorticoids Decreased use of glucose and increased resilience gluconeogenesis on ketone bodies & fatty acids Skeletal muscle: glycogenolysis, protein breakdown, amino acid release Growth hormone Complements glucorticoids effects Acts w/ glucorticoids Fasting & Starvation Fasting: going w/o food for multiple hours or a few days Starvation: weeks or months of food deprivation, or inadequate food intake Catabolism of stored triglycerides & structural proteins can give energy for several weeks Level of adipose tissue determines possible lifespan of going w/o food Nervous tissue & RBCs continue to break down glucose for ATP during fasting & starvation Metabolic Rate Total amount of energy produced & used by the body per unit time ○ Estimated by O2 level used per minute Components: ○ Basal metabolic rate (BMR) ▪ Energy used at rest ▪ 60% of metabolic rate ○ Thermic effect of food ▪ Energy used to digest & absorb food ▪ 10% of metabolic rate ○ Muscular activity ▪ Energy used for muscle contraction ▪ 30% of metabolic rate Body Temperature Regulation Balance between heat gain & loss ○ Heat is produced via metabolism ○ Heat is exchanged via radiation, conduction, convection, evaporation Greater temp difference between body & environment = Greater rate of heat exchange Regulated by a certain "set point" set by the hypothalamus Hypothalamic Thermostat Several negative feedback loops are in place to raise body temp when too low/high Mechanisms of heat conservation include: ○ Vasoconstriction ○ Sympathetic stimulation ○ Skeletal muscle contraction, aka shivering ○ Production of thyroid hormone Nutrition Nutrition is the absorption of nutrients from food Body's nutrient for each nutrient varies Balanced diet: diet that contains all nutrients required for homeostasis Malnutrition: unhealthy diet Kilocalories: measure of energy supplied by good & released via metabolism Vitamins table. TEST 4 MATERIAL Page 62 Reproductive System Part 1: Male Reproductive System Saturday, December 7, 2024 1:58 AM Intro Male and female reproductive systems include: ○ Gonads ▪ Produce gametes and hormones □ M: sperm, androgens □ F: ovum/eggs, estrogen ○ Ducts ▪ Transport gametes and/or the developing embryo ○ Accessory structures ▪ Secrete fluid ▪ Support embryo/newborn Male Reproductive System Include: ○ Gonads ▪ Testes □ Produce sperms & hormones ▪ Ducts ▪ Epididymis ▪ Vas deferens ▪ Ejaculatory duct + urethra ▪ Semen transport ducts □ Semen = sperm cells + seminal fluid ○ Accessory structures ▪ Seminal vesicle ▪ Prostate ▪ Bulbourethral glands □ Produce seminal fluid that support sperm cells Scrotum ○ Pouch formed by the abdominal wall divided into 2 sacs by a septum ○ Skin w/ dartos muscle leads to contraction during sexual arousal and causes tightening & wrinkling of the skin ○ Closer to birth the testes descend into the scrotum through the inguinal canal ▪ Inguinal then closes and the testes are suspended in the scrotal sac by a spermatic cord & cremaster muscles ○ Cryptorchidism: testes fail to descend into the scrotum and remain in the abdomen ▪ Here, the temperature is the same as overall body temp and no sperm are made □ Increases risk of testicular cancer Testes ○ Tunica vaginalis: parietal & visceral layer ○ Tunica albuginea: dense connective tissue capsule that surrounds the testes ○ Seminiferous tubules ▪ Long, coiled tubes packed inside the testes where sperm formation (spermatogenesis) takes place □ Sperm begin their development near the periphery (edge) of the tubules and are released as spermatozoa in the tubule's lumen ▪ Also has Sertoli/sustentacular cells/nurse cells that: □ Support, nourish, and protect developing spem □ Phagocytize germ cell (sperm) debris □ Secrete inhibin to regulate FSH release RECALL: FSH is released by the pituitary gland! □ Secrete androgen binding protein (ABP) that concentrates testosterone ▪ Between these tubules are Leydig/interstitial cells □ These are endocrine cells that secrete hormones and help regulate spermatogenesis ○ Temp Regulation of Testes ▪ Sperm formation requires a temp that is 2 - 3 degrees lower than body temp ▪ Testicular temp rises, causing the cremasteric muscles to relax □ Testes will then be pulled away from the abdomen and the testes temp drops Epididymis ○ A coiled tube on the back side of the testes that acts as the site of sperm maturation & capacitation ▪ During this process, sperm learns how to move and how to recognize & fertilize an egg □ Sperm that fail to do this are killed ○ Sperm are made in the seminiferous tubule then travel through the rete testis, through efferent ductules in the testes, then reach the epididymis ○ 3 FUNCTIONS ▪ Monitors and adjusts fluid produced by seminiferous tubules ▪ Recycles damaged sperm ▪ Stores & protects sperm, also facilitates functional maturation □ Sperm remains here for 10 - 14 days, then mature Maturation is when the sperm will gain motility and ability to fertilize via a process called capacitation ◊ If not ejaculated: sperm is broken down and reabsorbed by the body ◊ If ejaculated: sperm moves to the vans deferens w/ the help of peristalsis Accessory Glands ○ Produces semen ○ Essential glands include: seminal glands, prostate gland, bulbourethral gland, & testes (which creates sperm) ○ Seminal Vesicles ▪ Paired glands that produce a fluid which makes up 2/3 of semen (~60%) ▪ Contains fructose to nourish the spermatozoons & prostaglandins that are responsible for reverse peristalsis in the uterus □ Also contains protective enzymes □ These materials enhance sperm □ NOTE: Sperm do NOT use GLUCOSE for energy. They use FRUCTOSE. □ Reverse peristalsis of sperm is, essentially, the sperm moving in the opposite direction of normal peristalsis; this is them moving up the uterus rather than down & out ○ Prostate Gland ▪ Produces and secretes proteins into seminal fluid that helps activate sperm ▪ Produces enzymes and secretes citrate, calcium, & phosphate that buffer acidity of seminal fluid & the vagina □ Gives semen its alkaline property ▪ PSA levels are measured to monitor prostate head □ High PSA = prostatic cancer or BPH ○ Bulbourethral Glands (Cowper's Glands) ▪ Tiny pea-sized glands with secretions that neutralize any residual acidic urine ▪ Also lubricate penis head prior to intercourse SUMMARY: Male Reproductive Functions ○ 4 major functions ▪ Activation of spermatozoa capacitation ▪ Providing of nutrients that spermatozoa need for motility ▪ Propelling spermatozoa and fluids along the reproductive tract □ Mainly done by peristaltic contractions ▪ Production of buffers □ Counteracts acidic environments of the urethra and vagina Spermatogenesis: sperm formation ○ Diploid spermatogonia in the periphery of the seminiferous tubules divide via mitosis to create diploid primary spermatocytes, which will then divide via meiosis to create 4 haploid spermatids Spermiogenesis: transformation of spermatids to spermatozoa (aka sperm) Spermiation: release of sperm into the lumen of seminiferous tubules Sperm ○ Consist of: ▪ Head □ Contains the haploid nucleus w/ 22X or 22Y chromosomes □ Has a membrane sac w/ hydrolytic enzymes that aid fertilization ▪ Midpiece □ Contains mitochondria that give ATP for sperm motility ▪ Tail □ Flagellum that provides movement to sperm ○ About 300m are produced daily ○ Are made in the seminiferous tubules in the testes ▪ W/ their release, they're mixed w/ seminal fluid and secretions from 3 exocrine glands: □ Seminal vesicle: 60% □ Prostate gland: 5% □ Bulbourethral/Cowper's gland: ~1% ○ Semen = sperm + seminal fluid ▪ Is slightly alkaline (pH 7.2 - 7.7) ▪ Month 3 ▪ Child is referred to as AN EMBRYO □ THIS IS NOT A LIVING HUMAN BEING YET ▪ Period of embryological & fetal development ▪ Rudimentary versions of major organ systems appear ▪ Natural child death (miscarriage) typically occurs here □ These deaths are usually caused by chromosomal abnormalities ▪ Includes 4 MAJOR STAGES □ Cleavage Division of zygote into a clump of cells □ Implantation Attachment of the embryo to the uterus Trophoblast cells secrete enzymes to digest the uterus wall ◊ Allows the entire embryo to slowly become embedded in the uterus' endometrium ◊ Secretes hCG to maintain the uterine lining  NOTE: hCG is measured in urine pregnancy tests !!!! □ Placentation Formed during Month 3 At this point, maternal & fetal blood vessels do NOT join and the blood does NOT mix ◊ Also does NOT allow for passage of most microbes (w/ few exceptions) Allows for diffusion of O2, nutrients, and waste, but is NOT a barrier against drugs, like alcohol Secretes several hormones to support pregnancy and detaches from the uterus at birth (during the afterbirth phase) □ Embryogenesis Embryo body begins to separate from the embryonic disc Beginning stages of formation of the embryo's body and internal organs Folding & differential growth of embryonic disc creates a build that projects into the amniotic cavity