Final Review Flashcards
What are the possible effects of exposure to toxins during the pre-implantation period? Why?
- No effect, slight decrease in growth, or lethality
- As the fate of the cells has not yet been determined (pluripotent nature), providing them with great restorative capacity
- Also, there is a decreased exposure to toxins due to poorer accessibility of the conceptus (not yet attached to uterine wall)
What type of drug is Dilantin? What defects does it result in?
- Anti-epilectic drug
- Fetal hydantoin syndrome
What type of drug is Thalidomide? What defects does it result in?
- Immunomodulatory drug
- Limb and ear abnormalities
What type of drugs are antineoplastic drugs? What defects do they result in?
- Chemotherapy drug
- Congenital abnormalities
What type of drug is Diethylstilbestrol? What defects does it result in?
- Endocrine disruptor
- Uterine and cervical defects
What type of drug is Dextromethorphan? What defects does it result in?
- Cough-suppressant
- CNS abnormalities
What are the effects of excess fluoride?
Spina bifida occulta
What are the effects of iodine deficiency? What are its characteristics?
Cretinism
Which nutrient deficiencies are anti-convulsants associated with?
Folate and zinc deficiencies
What are characteristics of alcohol-related birth defects (ARBD)?
- Microcephaly
- Heart and lung malformations
- Minor physical abnormalities
Differentiate anencephaly and exencephaly.
- Anencephaly implies that the brain is exposed, due to the lack of skull
- Exencephaly implies that the brain protrudes out of the skull
What substances does the placenta synthesize for fetal use?
- Glycogen
- Lactate
- Cholesterol
What indicator is used to estimate the requirements (RDA) for carbohydrates?
Minimum amount of glucose required by the brain without depending on fat or protein as an alternative source
What indicator is used to estimate the requirements (AI) for dietary fiber?
Median intake observed to achieve the lowest risk of coronary artery disease
What are the four benefits of fiber? (4)
1) Amelioration of constipation and diverticular disease
2) Fuel for colonic cells
3) Decrease in blood glucose and lipids
4) Acting as a source of nutrient-rich low-energy foods (increases satiety and decreases obesity)
What DRI is used to estimate the requirement for magnesium? How is it established?
- RDA
- Based on total body magnesium, assessed using balance studies
What DRI is used to estimate the requirement for potassium? How is it established?
- Adequate Intake (AI)
- Based on the physiological functions of an adequate intake of potassium
What is the importance of organic anions that are associated with potassium?
- They are converted to bicarbonate after absorption
- Bicarbonate may act as a buffer to neutralize acids from the diet
What occurs if there is a deficiency in bicarbonate precursors?
The body must use another type of buffer, which is normally drawn from the bone matrix, leading to increased bone turnover
Where is potassium largely contained?
Intracellularly
What is the major function of riboflavin?
Functions as a coenzyme in various oxidation-reduction reactions, involved in several metabolic pathways and energy production
What three factors determine the requirement for riboflavin? (3)
1) Erythrocyte glutathione reductase activity coefficient
2) Concentration of riboflavin in RBCs
3) Urinary riboflavin excretion
What determines the requirement for niacin?
Urinary excretion of niacin metabolites, as an excess of niacin is methylated in the liver for excretion in urine
What DRI is used to estimate the requirement for choline? How is it established? What factor does it take into consideration?
- AI
- Assessed by serum alanine aminotransferase levels
- The prevention of liver damage
What factor determines the requirement for vitamin E?
- The correlation between hydrogen peroxide-induced erythrocyte lysis and blood a-tocopherol
- Analysis of the level of a-tocopherol that protects against hemolysis caused by hydrogen peroxide
What is the difference between tocopherols and tocotrienols?
- The side chain of tocopherols are saturated
- The side chain of tocotrienols are unsaturated
The concentration of the various forms of vitamin E in plasma are dependent on what?
Their affinity with hepatic a-tocopherol transfer protein (a-TTP)
How does the recommendation for potassium vary during pregnancy?
The AI does not change
How does the recommendation for biotin (vitamin B7) vary during pregnancy?
The AI does not change
How does the recommendation for vitamin E vary during pregnancy?
The RDA does not change