Explain the functional significance of the differences in epithelial types among

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Explain the functional significance of the differences in epithelial types among Powered By Docstoc
Explain the functional significance of the differences in epithelial types among
the three pharyngeal sections.

  • Pseudostratified C. C. Epi. in nasopharynx for aiding in respiratory function

  • Stratified Squamous in oropharynx and laryngopharynx for protection from
    mechanical abrasions from swallowed food.
Name 2 similarities and 2 differences of chief cells and parietal cells

   Similarities: both found in gastric glands, both stimulated by gastrin and
   enteric reflexes, both inhibited by duodenal hormones, both needed for
   proper digestive function

   Differences: chief cells secrete pepsinogen, parietal cells secrete HCl and
   intrinsic factor. Chief cell secretion relies on parietal cell secretion for
            What are the three basic categories of liver function?

• Metabolic Regulation: carbohydrate, protein, and fat processing, etc.

• Hematological Regulation: antibody recycling, hormone recycling, detox,

• Bile production
   What is the difference between peristalsis and segmentation?

• Segmentation is mainly used for mixing of contents, not so much propulsion

• Peristalsis is specifically for propulsion of food and chyme through the tract.
Achlorhydria is a condition in which the stomach stops producing hydrochloric acid
and other secretions. What effect would achlorhydria have on the digestive process?
On red blood cell count?

  Very little if any digestion would occur in the stomach, leading to a high amount
  of mostly undigested proteins entering the duodenum. This can lead to mal-
  nutrition and intestinal pain due to bacterial activity. Since intrinsic factor is
  secreted in the stomach, there would be a low number of mature red blood cells,
  pernicious anemia.
 What are two distinct functions performed by the pancreas?

• Endocrine: insulin and glucagon for blood glucose regulation

• Exocrine: digestive enzymes and alkaline buffer
A 19 year old male walks into a hospital emergency room and reports the following
symptoms: 103 fever, pain in the neck, headache, and swelling in front of and below
the ear. What is your diagnosis?

  • Symptoms point to an infection of the parotid salivary glands, most likely
        Many visceral smooth muscle networks show rhythmic cycles of activity in
        the absence of neural stimulation due to the presence of:
        a. direct contact with motor neurons carrying impulses to the CNS
        b. an action potential generated and conducted over the sarcolemma
        c. the single motor units that contract independently of each other
        d. pacesetter cells that spontaneously depolarize and trigger contraction
           entire muscular sheets

d) pacesetter cells that spontaneously depolarize and trigger contraction
   entire muscular sheets
What are the nervous and chemical mechanisms that regulate the digestive system?

  Nervous mechanisms include communication from the CNS through sympathetic
  and parasympathetic neurons. There are also long and short reflexes utilizing the
  submucosal and myenteric nerve plexuses.

  Chemical mechanisms are primarily hormones from stomach and duodenum.
The enteroendocrine cells of the intestinal crypts are responsible for
producing the intestinal hormones:
a. gastrin and pepsinogen (pepsin)
b. biliverdin and bilirubin
c. enterokinase and aminopeptidase
d. cholecystokinin and secretin
e. gastrin and glucagon

            d) cholecystokinin and secretin
An increase in the rates of glandular secretion and peristaltic activity
in all segments of the small intestine are a result of the:
a. presence of intestinal juice
b. gastroenteric reflex
c. gastroileal reflex
d. action of hormonal and CNS controls

                  b) gastroenteric reflex
The contractions that force fecal material into the rectum and produce the
urge to defecate are called:
a. primary movements
b. secondary movements
c. mass movements
d. bowel movements

         c) mass movements
   The two positive feedback loops involved in the defecation reflex are:
   a. internal and external spincter muscles
   b. the anorectal canal and rectal columns
   c. stretch receptors in rectal walls and sacral parasympathetic system
   d. mass movements and peristaltic contractions

c) Stretch receptors in rectal walls and sacral parasympathetic system
Triglycerides coated with proteins create a complex known as:
a. micelle
b. co-transport
c. glycerol
d. chylomicron

                  d) chylomicron
Salivary enzymes in the oral cavity begin the digestive process by acting
on _____________________.

            Starch, complex carbohydrates
The two intestinal hormones that inhibit gastric secretion to some degree are
_____________________ and _______________________.

                         GIP, CCK, Secretin
A vitamin that is produced in the colon through bacterial action and is
absorbed with other lipids is __________________.

                            Vitamin K
Nutrients that can be absorbed without preliminary processing but may
involve special transport mechanisms are
a. nucleic acids, minerals, enzymes
b. sugar, amino acids, fatty acids
c. water, electrolytes, vitamins
d. lactose, fructose, galactose

         c) water, electrolytes, vitamins
Describe the enteric plexus. In what layers of the digestive tract are the
submucosal and myenteric plexuses found?

Collection of sensory and motor neurons embedded in the wall of the alimentary
canal. It plays a huge role in regulating digestive function using stretch and
chemo receptors to sense changes, and motor neurons to deliver messages for
motility and secretions.

submucosal plexus is found at the boundary between the submucosa and the
circular layer of the muscularis externa

myenteric plexus is found sandwiched between the circular and longitudinal layers
of the muscularis externa
The blind pockets lined by simple cuboidal epithelium that produce
pancreatic juice are called__________________.

                Pancreatic acini
Name the sudden rush of bicarbonate ions into the interstitial fluid during the gastric
phase, and explain its origin.

 Alkaline Tide. As the parietal cells produce hydrochloric acid by the carbonic
 acid-bicarbonate buffer equation, high amounts of bicarbonate ion is released
 into the blood stream. This causes a brief increase in blood pH, metabolic alkalosis.
        What are the three phases involved in the regulation of gastric
        function and what regulatory mechanism(s) dominate each?

• Cephalic Phase: CNS neural stimulation via parasympathetic pathways

• Gastric Phase: Local reflexes triggered by stretch and chemoreceptors, along
  with hormonal regulation by gastrin, from G-cells.

• Intestinal Phase: Local reflexes triggered by stretch and chemoreceptors, along
  with hormonal regulation by CCK, secretin, and GIP
The primary function of secretin is to
a. decrease duodenal submucosal secretions
b. increase in release of bile from the gall bladder into the duodenum
c. increase in secretion of buffers by pancreas
d. increase gastric motility and secretion

 c) increase in secretion of buffers by the pancreas
Once a bolus of food has entered the laryngopharynx, swallowing
continues involuntarily due to the:
a. swallowing reflex
b. size of the bolus
c. peristaltic activity
d. a, b, and c are correct

             d) a, b, and c are correct
Accelerated secretions by the salivary glands, resulting in the production
of watery saliva containing abundant enzymes, are promoted by:
a. sympathetic stimulation
b. parasympathetic stimulation
c. the gastroenteric reflex
d. excessive secretion of salivary amylase

          b) parasympathetic stimulation
When two fluids are separated by a selectively permeable membrane,
water tends to flow into the solution that has the:
a. lower concentration of solutes
b. same osmolarity on each side
c. higher concentration of solutes
d. proper osmotic equilibrium

         c) Higher concentration of solutes
The filtration process within the renal corpuscle involves passage
across three physiological barriers, which include the:
a. podocytes, pedicels, slit pores
b. endothelium, basement membrane, glomerular epithelium
c. capsular space, tubular pole, macula densa
d. collecting tubules, collecting ducts, papillary ducts

b) endothelium, basement membrane, glomerular epithelium
Trace the pathway of a drop of filtrate from the time it goes through
the filtration membrane in the glomerulus until it enters the collecting
ducts as concentrated urine.

     Glomerular capsulePCTLoop of HenleDCT
What two chemicals are secreted by the juxtaglomerular apparatus?

                       EPO and renin
During the micturation reflex, increased afferent fiber activity in the
pelvic nerves facilitates:
a. parasympathetic motor neurons in the sacral spinal cord
b. sympathetic sensory neurons in the sacral spinal cord
c. the action of stretch receptors in the wall of the bladder
d. urine ejection due to internal and external sphincter contractions

a) Parasympathetic motor neurons in the sacral spinal cord
Blood supply to the proximal and distal convoluted tubes of the nephron
is provided by:
a. peritubular capillaries
b. vasa recta
c. afferent arterioles
d. cortical radiate arteries

         a) peritubular capillaries
The three processes involved in urine formation are:
a. diffusion, osmosis, filtration
b. cotransport, countertransport, facilitated diffusion
c. regulation, elimination, micturation
d. filtration, reabsorption, secretion

         d) filtration, reabsorption, secretion
Along with the urinary system, the other systems of the body that
affect the composition of body fluids are:
a. nervous, endocrine, and cardiovascular
b. lymphatic, cardiovascular, and respiratory
c. integumentary, respiratory, and digestive
d. muscular, digestive, and lymphatic

       c) integumentary, respiratory, and digestive

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