Katwa Flashcards
Small Intestine: What is absorbed by each portion and identifier
- Duodenum
- absorb iron
- Brunner’s Glands (Submucosal Glands)
- Jejunum
- Absorb Folic acid
- Plicae circularis
- Ileum
- Absorb vitamin B12 and Bile salts
- Peyers patches
Small Intestine Cells
- Absorptive Cells
- microvilli
- absorb water
- Goblet cells
- increase towards rectum
- produce mucus
- M Cells
- APCs-Dendritic Cells
- Paneth’s Cells
- at base of cell
- Lysozyme=antibacterial
- Enteroendocrine
- Stem Cells
Compensation
- Does not correct the original problem
- second abnormality is created to compensate the orignal cause
Respiratory Compensation
- Respiratory compensation for metabolic acidosis more effective than for metablic alkalosis
Rest and Digest
- Increased Splanchic Blood flow maintains intestinal viabliity
- serves as source/sink for material transported across GI tract epithelium
Intermittent fasting
- no food for 2-4 days
- mainly reduces inflammation and oxidative stress: leads to increase
- mitocondrial number and quality
- cellular regenerative process
- Good for immunocompromise:
- boosts immunity and may reverse it
Four processes of the digestive system? Which are continuously regulated?
- Digestion
- Absorption
- Motility
- Secretion
Motility and secretion continuously regulated
What stimulates the four processes of digestive sytem?
- ENS (enteric) and CNS
Food Processing: Phases of Digestion
integrated response to meal
- Cephalic Phase
- oral, esophageal
- initiated by stimuli
- characterized by activated PNS
- prepares stomach for food and digestion
- Gastric phase:
- storage, mixing, digestion and protection
- from bacterial invasion and auto digestion
- Intestinal Phase: MOST IMPORTANT
- Digestion and Absorption
- bicarbonate
- mucus
- bile
- digestive enzymes (Enteropeptidase)
- Large intestine
- concentrates water for excrecretion (mass movement)
- Digestion and Absorption
Intermittent Fasting: 5 benefits
- Improves immune regulation
- Stimulates cellular autophagy
- slow down aging process
- Improves genetic repair mechanisms
- Improves Insulin Sensitivity
- Chronic Diseases:
- reduced CVD
Gut nickname
- The inner tube of Life:
- Powerhouse of Energy
- energy homeostasis
- 2nd Brain
- immune integrity
- Powerhouse of Energy
Most imoprtant function of digestive system
- Continuous supply of water, electrolytes and nutrients to the body
- AND
- Elimination of waste products through anus
Major challenges of Digestive system
- efficient extraction of essential nutrients
- Protection against Autodigesiton
- Protection against bacterial infection
- Maintaining mass body fluid balance
Deglutition
swallowing
Eructation
Burping
Emesis
Vomiting
Borborygmi
bowel sounds
Flatus
intestinal gas
Postprandial
after eating
Extrinsic innervcation of the GI tract
- Subdivisions of ANS
- A-PNS
- parasympathetic
- excitatory
- Medulla: VASOVAGAL REFLEX
- Vagus nerve innervates the:
- esophagus
- stomach
- Pancreas
- Intestine
- Upper colon
- Vagus nerve innervates the:
- Sacral Spinal Cord
- Pelvic nerve innervates the:
- lower descending colon
- rectum
- anus
- Pelvic nerve innervates the:
- B-SNS
- sympathetic
- inhibitory on GI fxn
- innervate:
- Superior Cervical ganglion
- Prevertebral ganglia
- celiac
- superior mesenteric
- inferior mesenteric
Vasovagal reflex
- Reflex in which bot afferent and efferent pathways are in vagus nerve
- coordination of gastric, small intestine, and pancreatic digestive functions
Spinal Cord injury: GI
C6=abnormal defecation
location of ENS
- Myenteric Plexus
- Auerbach’s plexus
- Submucosal Plexus
- Meissner’s Plexus
ENS
- aka “little or second brain”
- Highly innervated
- more neurons that spinal cord (100 million)
- Independent of CNS
Hirschsprung disease
- aka Congenital Aganglionic megacolon
- polygenic disorder
- Muations in a least 3 different classes of genes
- No Meyenteric (auerbach’s plexus) and Submucosal (Meissner’s) plexus
- Functional obstruction of Distal part of the colon and rectum
- caused by the absence of enteric ganglia
Celiac Disease
- Gluten Enteropathy
- damage to villi/microvilli due to autoimmune response of T cells
- Small intestine
Enamel:
- Highly mineralized acellular tissue
- Calcium phosphate crystals comprise 99% of dry weight
- Crystals resemble hydroxyapatite
- Crystals packd to form enamel rods
- space b/w crystals=water (11%) and organic (2%)
- Translucent
Saliva
- Protects Enamel:
- contains:
- calcium
- phosphate
- Fluoride
Crystal Dissolution
- Solubility product of hydroxyapatite KSPHA
- concentration of mineral of teeth in solution
- Ion Activity Product of Hydroxyapatite IAPHA
- Solubility of active ions in the solution
- @equilibrium; pH=7–>no disolution
- KSPHA=IAPHA
Hydroxyapatite @pH less than 7
- Apatite solubiliity increases
- Acid causes disolution of enamel
- loss of Calcium and Phosphate
- PO43- binds 2 Hydrogens
- IAP decreases
- solution is unsaturated and more hydroxyapatite dissolves until saturation is reestablished
Critical pH Value of Enamel
- Hydroxyapatite=5.5
- Fluorapatite (FA)=4.5
Define critcal pH value
- When IAPHA=KSPHA , the solution is saturated and no demineralization or remineralization will occur
- pH that corresponds to this saturation=critical pH
Critical pH for dentin
- 6.5
Process of demineralization
- Bacteria
- ferment carbohydrates
- produce acid which decreases the pH
- Loss of calcium, phosphate and carbonate from tooth
Large Intestine: Identifiers
- No Villi
- A lot of GOBLET Cells
- Teniae Coli
- Haustra
Zenker’s Diverticula
- Severe halitosis
- Weakening of muscle wall
- lack of coordination of swallowing
Stomach Cells
- Surface mucous cells
- thick alkaline mucus
- Undifferentiated (Stem) Cells
- Mucuous Neck cells
- Parietal (Oxyntic) cells
- Boobs
- Secrete HCL and IF
- pale and pink
- Chief (zymogenic) cells
- gastric lipase
- proenzymes (pepsinogen to pepsin)
- Enteroendocrine cells