Anatomy ll Final
BSCI202_StudyGuide_LEx4
Lecture Exam 4 (Final) is cumulative.
Approximately 30% of the exam will be on the Digestive System.
Approximately 70% of the exam will be on all the other organ systems studied this semester (blood and immune system, cardiovascular, respiratory, urinary, and reproductive).
You should review the study guides for LEx1, LEx2, and LEx3, to prepare for this cumulative portion of the exam.
Digestive System:
Name, identify, and label the main organs and the accessory glands of the digestive system
Alimentary canal:
Mouth: uvula and soft palate prevent food from entering the nasopharynx + mechanical processing and chewing
Pharynx: uses peristalsis with longitudinal and circular muscles to the esophagus - this process is voluntary…think swallowing
Esophagus: the upper esophageal sphincter opens and closes concerning the bolus - involuntary control - conduct via peristalsis (circular and longitudinal muscles) - conducts only via stratified squamous epithelium cells
Stomach: accepts the food via cardio esophageal sphincter or lower esophageal sphincter (done through peristalsis) + has circular, longitudinal, and oblique muscles + intrinsic factor: protein produced in the stomach that helps absorb vitamin B12 + chyme is further mixed with secretion and sent through the pyloric sphincter → duodenum
Small intestine
Large intense
anus
Accessory organs:
Tongue: mechanical processing and forming the bolus + taste buds to sense food + lubricates structures
Teeth: masticate/mechanical breakdown of foods (incisors, premolars, molars and canines)
Gallbladder
Liver
Pancreas
Salivary glands: sublingual, submandibular, and parotid - make Saliva
mucus (protein and gel-like) - help form the bolus and dissolve chemicals promoting gustation
serous fluid as amylase which breaks down starch (carbohydrates) into complex sugars
Name the main 4 functions of the digestive system and what they mean. Provide concrete examples of these functions, and what structures allow the system to fulfill these functions.
Ingestion: mechanical and chemical breakdown
Propulsion: moving the bolus through the GI tract
Digestion
Mechanical breakdown
Chemical breakdown
Absorption
Defecation
Explain the mechanisms involved in deglutition; “swallowed substances have the right of way over airflow” – discuss how this is accomplished
Food is chewed and masticated by the teeth and the bolus made by the tongue is broken down by the saliva released from the salivary glands such as amylase, food is then propelled towards the back of the throat behind the oropharynx
The nasopharynx is closed by the soft palate and the uvula allowing food to pass through to the laryngopharynx
Describe the 4 layers of the digestive system, and what they are formed by at the different layers of the system.
Mucosa: protects, barrier, immune system, and mucus
Stratified squamous epithelium (until stomach, small intestines and large intestines: simple columnar)
Lamina propria
Muscularis mucosa
Submucosa: provide with blood vessels, nerve endings and immune response (areolar connective tissue)
Muscularis externa: circular muscles and longitudinal muscles (oblique if stomach)
Serosa: covering for the alimentary tract
Areolar connective tissue
epithelium
The mechanism of swallowing and the different structures involved.
Buccal phase → pharyngeal → esophageal
Food is chewed (mechanical breakdown) and moistened with saliva from salivary glands and pushed to the back of the pharynx
Inside the back of the throat is the pharynx where the tongue rolls back and the soft palate and uvula block the nasopharynx for the bolus to involuntarily move through into the esophagus - the epiglottis covers the trachea
The upper esophageal sphincter poems allowing the bolus to enter and the swallow reflex to send the bolus down the esophageal tract - which has the upper esophageal sphincter relaxing - is involuntary
Stomach: structure of the gastric mucosa including gastric pits and glands, their cells, roles, and secretions (HCl, zymogens, intrinsic factor, hormones)
Inside the stomach lies gastric pits which lead to gastric glands, which produce digestive juices and enzymes
Chief cells: synthesize and release pepsinogen which then becomes pepsin by HCl
Parietal cells: epithelial cells that secrete hydrochloric acid (opens up the proteins which allows the pepsin to chop it up nice and easily) and intrinsic factor (absorbs vitamin B12)
Mucous neck cells: secrete mucus to line the interior of the stomach
G cells (enteroendocrine): G cells stimulate GASTRIC activity which means they synthesize and secrete gastrin which stimulates parietal cells to stimulate HCl + stimulate ECL cells to stimulate histamine which also stimulates HCl secretion + stimulates D cells…
D cells (enteroendocrine): secrete somatostatin which inhibits acid secretion in the stomach
S cells: releases secretin from the small intestines to act upon the pancreas to release bicarbonate to buffer the pH and raise it back to levels thare not too acidic in the chyme – alkaline conditions
CCK: CCK is released by I cells towards the pancreas to trigger the release of pancreatic juices and bile to help the duodenum in digestion – triggered by fats in the duodenum
Mechanism and role of peristalsis and segmentation, compare and contrast.
Segmentation: movies in many different directions due to circular muscles that lead to a mixture of the bolus – a homogeneous type of mixture
Important in the stomach and the small intestines
Peristalsis: moves food up and down
Important in the esophagus
In the small intestines such as in the duodenum, cholecystokinin is released causing it to trigger the gallbladder and pancreas to contract releasing bile and pancreatic fluids
Specifically fats or teh associates triglycerides and fatty acids trigger CCK to trigger pancreas and liver
4 layers of the stomach
Muscularis externa (longitudinal, circular and oblique muscles)
Mucosa: simple columnar epithelium + secretory cells (mucous cells + gastric dips that have glands with gastric juices)
Parietal cells produce HCL (intrinsic factor + low pH + turns pepsinogen into pepsin)
HCL secretion is stimulated by H+/K+ ATPase pump, PSNS, gastrin (g-cells), histamine
Chief cells produce pepsinogen (ready for protein breakdown) + lipases (fat) + rennin (milk)
Mucous neck cells produce mucus and help protect the lining of the stomach
enteroendocrine cells: produce hormones
G cells: gastrin - promotes movement/separation of food - allows enzymes to be in contact + mucus + pepsinogen (chief cells) + HCL (parietal cells)
D cells: somatostatin - a hormone that inhibits the production of acid in the stomach
ECL cells: histamine stimulated by G cells and signal for HCl release from the parietal cells
Submucosa
Serosa
Regulation of gastric secretion: 3 phases, hormonal and neural regulations.
Cephalic Phase
Thought of food activates centers in the brain to prepare the stomach that something is coming and stimulates secretory activity (chief cells, parietal cells etc) just the thought triggers g cells and distention
Gastric Phase
Mechanoreceptors, chemoreceptors, and baroreceptors signal that food has arrived (enteric and sympathetic nervous system fire secretion)
Sensory afferent fibers from the vagus nerve lead on a message through the sympathetic nervous system stimulating the stomach that leads to stimulation of activity to send to small intestines
Intestinal Phase
Activity at the duodenum in the small intestine → when the chemoreceptors at this point are triggered with chyme then some gastric secretion occurs causing distention and sending negative feedback to secretion and glands for more absorption
Pyloric sphincter can be contracted to prevent chyme to going through small intestines
G cells and D cells are still here and impact small intestines
Movement in the stomach:
3 extrinsic reflexes in the stomach**
Explain the relationship between the stomach and pernicious anemia
Parietal cells produce intrinsic factor which is a protein produced in the stomach to help absorb vitamin B12
The pernicious anemia is an autoimmune response which results in a deficiency of intrinsic factor, which in turn prevents the proper absorption of vitamin B12 from the diet and attacks these parietal cells (not chief → they make pepsinogen, while parietal cells make hydrochloric acid and intrinsic factor)
Small intestine: gross anatomy and structures that form the small intestines, their functions, and secretions. The histology of the small intestine and explain how it promotes the functions of the small intestine.
Duodenum (attached to the pyloric sphincter in the stomach)
Jejunum
Ilium (goes to ileocecal valve → cecum of the large intestine)
Most absorption in the body occurs here (by intestinal cells and pancreatic enzymes and bile released by the liver and stored in the gallbladder)
They help absorb by folding themselves over - villi
Made up of lots of microvilli cells → help with surface area for absorption
Circular folds
It is also made up of simple columnar epithelium
The pancreas and liver work together to break food into simple components
Water, electrolytes, lipids, fructose (Na/ glucose/ amino acids reabsorbed through primary transport)
Nutrients travel into the bloodstream toward the liver where metabolism and catabolism occur
Large intestine: gross anatomy, histology and functions of the large intestine. Identify the 8 regions of the large intestine, Importance of the microbiota, defecation reflex
Enters through the celiac sphincter and in the large intestines we need more power for the solids
Absorbs: water, vitamins, bile salts, organic wastes, toxins → leaves with feces (undigested food, bacteria and water)
Does not have villi → is simple columnar epithelium with goblet cells
It still has the four layers (mucosa, submucosa, muscularis externa and serosa)
has haustra (small pouches that give its appearance)
Fiber worlds in the way of osmosis
Gatorade and candy help us retain water through osmosis of glucose and electrolytes having us express ADH to retain water
Accessory organs: describe the main functions and secretions
Salivary glands: produces saliva
Liver: produces bile → fat emulsifier (digest lipids in the small intestines)
Gallbladder: concentrates bile salts made by the liver
Pancreas: producing digestive enzymes, called pancreatic juices, which break down carbohydrates, fats, and proteins into smaller molecules that the small intestine can absorb
Describe the absorption of sugars, proteins, and lipids: location, cells,s and mechanisms involved. And lactose intolerance featuring lactase
Metabolism:
Define metabolism, anabolism, catabolism
Metabolism: sum of all biochemical reactions in the body
Anabolism: reactions that build larger more complex molecules
Catabolism reactions that break complex structures into simpler structures
:
Discuss glucose catabolism in the presence or absence of O2, input, output and location
Broken down by amylases and brought into the cell → glycogenesis creates longer chains of glucose which happens in the liver and skeletal muscles for whenever it is needed
Gluconeogenesis is the new creation of glucose which mainly happens in the liver and occurs in glycemia
Glycolysis is the breakdown of glucose into ATP or pyruvate
Glycogenesis is the process of breaking down glycogen into glucose to produce energy
Associate absorptive and postabsorptive phases with glucose and glycogen catabolism and anabolism.
Describe briefly the role of hormones on appetite.
Format for the Lecture Exam 4:
Lecture Exam 4 (190 total points) -
Anatomy and Physiology 2 (BSCI202) - in person
Dr. Goytia (office BPS 2230)
Classroom setup: Have a spare seat between you and your neighbor or you may be required to move during the exam which will be disruptive for you.
There are 3 different versions of the exam.
You will have 100 minutes to complete this exam.
No fill in the diagram questions
No Open-ended questions for the Final Exam.
No extra-credit assignment is associated with the Final Exam.
Exam Viewing will be held in person on Thu 12/19, 10:30am - 1pm, in BPS 1230.
During the exam:
Keep a distance from peers. Keep your eyes to yourself.
You will not be allowed to leave the room until you submit your exam.
You must write your answers in the bubble sheet AND on the exam file. You must return both the exam booklet AND the bubble sheet, as they will be used to confirm any doubts regarding answers on the bubble sheet. If either the bubble sheet or the exam booklet are not returned, the exam will be graded 0.