Transcript iphy 3430 9-22

IPHY 3430 9-22-11
No review session this week
Exam key posted between Ramaley N176 and
N168 in glass case.
You have until the next exam to challenge
your score on CU Learn and/or explain to me
your thoughts on a given question.
ULCERS
Protection against stomach acid
1. Mucosal barrier
2. Membranes of mucosal cells impermeable to acid
3. Tight junctions between cells
4. Rapid turnover of cells
Ulcers, cont.
Causes:
1. Helicobacter pylori
a. secretes urease
b. flagellae help them tunnel into stomach wall
c. avoid acid producing areas of
stomach
2. Alcohol, non- steroidal, anti-inflammatory
drugs (aspirin, etc)
3. Stress induces overproduction of HCl
Vomiting
stimuli-->
Vomiting center in
medulla
--> motor output
--> PNS and SNS output
Vomiting, cont.
Stimuli:
a. toxins in stomach
b. pressure receptors at back of throat, tongue
c. elevated intracranial pressure
d. dizziness
e. emotional stress (Psychogenic)
Vomiting, cont.
Motor output:
1. contraction of inspiratory muscles (esp. diaphragm)
2. glottis and epiglottis closure
3. abdominal muscles contract
4. uvula elevated to close off nasal passages
5. jaw thrusts out, opening pharyngoesophageal
sphincter
PNS output:
Salivation, nausea
SNS output:
sweating, increased heart rate
CNS inhibition: Respiratory center inhibited so no
breathing
Diarrhea
Causes:
1. Infectious agents
2. Food allergies
3. Foods that stimulate gut motility
4. Psychogenic causes
Mechanism:
Impairment of Na+ uptake, active transport of
Cl- into the gut lumen, K+ , HCO3- and water
follow back into the gut
Distension of gut wall causes contractions
Constipation
Causes:
1. Low fiber food
2. Lack of exercise
3. Inadequate fluid intake
4. Drugs that decrease gut motility
5. Chronic use of laxatives
Hemorrhoids
Causes:
1. all factors that cause constipation
2. pregnancy
Essential components of diet
1. Energy (homeostasis in body weight)
2. Water (homeostasis in body water content)
3. Ions (homeostasis in ionic content)
4. Vitamins
5. Essential fatty acids
6. Essential amino acids
Regulation of food intake
Long-term (regulation of body energy content)
Fat cell size-->hypothalamus--> food intake
Fat cell size -->  leptin --> hypothalamus
--> stimulate food intake-->  fat cell size
Problem: increase in set point with age
Fig. 17-2, p. 637
Dieting…
You vs. your hypothalamus
Other things….
1. Not all fats are bad
2. Avoid saturated fats, cholesterol
3. Refined sugars in large quantity over long
periods blow out cell receptors for insulin
4. Eat only when you are hungry
5. Eat a varied diet
6. Exercise, exercise, exercise
Foods high in saturated fat
chocolate
peanut butter
spreads and dips
poultry skin
margarine
goose and duck
whipped toppings
prime beef
fatty cuts of pork and lamb
whole or 2% milk
ice cream
Macadamia nuts
shrimp
An obesity epidemic
13% of 6-11 yr old kids are obese
(2 x 1980 percentage)
14% of 12-19 yr olds are obese
(3 x 1980 percentage)
More than just lack of exercise and too much fatty
foods?
Environmental endocrine disruptors
Lab animals