Week per week study questions Flashcards
what are the ADGs? purpose ?
ADGs- Australian dietary guidelines. Their purpose is as a nutrition education tool that translates scientific evidence on the role of food nutrient composition into consumer friendly information. Targeted at the healthy general population aimed at preventing chronic disease and deficiency.
Five ADGs
- to maintain healthy weight: Be physically active + choose amounts of food and drink to meet your energy needs
- support and promote breastfeeding
- limit saturated fat, sugar, added salt and alcohol
- care for your food and store it safely
- enjoy wide variety of foods from 5 food groups everyday. + drink plenty of water.
What is the AGHE?
• How does it translate to a daily meal plan?
Australian guide to healthy eating.
gives proportions of the different food groups you should be consuming everyday.
- visual representation of recommended portion sizes of different food groups. Whole foods- not macronutrients.
- giving you a representation of what your plate should look like: proportions in reference to each other.
• What are the NRV’s (complete descriptions of
the 6 references in terms of what they aim to achieve, how they are determined)
Nutrition reference values- a set of targets for macro and micronutrients, age and sex specific. Aimed at preventing deficiencies and toxicity in the general healthy pop.
- EAR: estimated average requirement - (determined by biomarker- sign of deficiency- 50% showed deficiency 50% didn’t.
- RDI: Recommended dietary intake (97-98% showed no deficiency)
- AI: adequate Intake (used when EAR cannot be determined)- average daily nutrient level based on observation or experimentally based approximations or estimates of nutrient uptake of a group of apparently healthy people.
- UL: upper limit (10% showed toxicity) - upper limit like to pose no adverse health effect on most individuals in the general population.
- SDT: suggested dietary targets - Daily intake of certain nutrients that may help prevent chronic disease.
- EEL: estimated energy requirements. - average dietary energy intake that is predicted to maintain energy balance in a healthy adult of defined age, gender, weight, height and physical activity level consistent with a healthy person.
- AMDR- acceptable macronutrient distribution range (= maximise general health outcomes) (+14)
• What must be stated on the nutrition information panel?
The ingredients- from most to least
• What are the definitions of (and the differences between) digestion and absorption?
digestion- breaking down foods into molecules that can be absorbed (by enterocytes + delivered into blood)
absorption- uptake of monomers and micronutrients from the lumen of the GIT through the absorptive cells into the blood and lymph for transport through the blood.
• Trace a cheese and salad sandwich through the digestive processes, naming the various structures and secretions involved in the digestion and absorption of food constituents in the sandwich
Month (mechanical and chemical digestion)
| Saliva (lysosomes, mucus, salivary amylase, lingual amylase)
|
oesophagus
(lower oesophageal sphincter)
Stomach
(secretions: HCL, gastric lipase, gastrin, mucus)
(pyloric sphincter)
SI
(secretions: gastrin, CCK, secretin, gastric inhibitory peptide)
(iliocecal sphincter)
LI
rectum
Anus
• Describe the different forms of absorption
- passive
- facilitated: carrier protein
- Active: requires ATP
- endocytosis : cell wall engulfs substance.
• What is the entero-hepatic recirculation?
recycling of bile in the liver-
• How are nutrients being transported in the body once
absorbed?
In blood- CVS- (via capillaries - water soluble) to liver then to other organs and tissues and lymph- lymphatic system (via lacteals) fat soluble and larger particles- enter CVD at thoracic duct)
• What occurs to indigested food compounds before they leave the body?
get fermented by the gut bacteria in the colon
• What are prebiotics and probiotics ? What is their respective function?
Prebiotic- non-digestible carbs that feed bacteria and promote their growth.
probiotics- live bacteria, identical to what is found in gut. populate gut adequately.
Define metabolism, catabolism, anabolism, energy
metabolism, substrates, intermediates, products
Metabolism: biochemical reactions that occur in the body (biochemical reactions from substrate to products)
product: compound resulting from pathway
intermediates: compounds formed and used throughout pathway
substrate: start of pathway compounds.
anabolism: (use energy) pathways that build molecules (small-> big)
catabolism: (release energy) pathway that break down molecules (big –> small)
energy metabolism: reactions that result in the production of energy- breaking down macronutrients to produce energy.
• What are the Cori cycle and the citric acid cycle?
cori cycle: converts lactic acid back to glucose in liver.
citric acid cycle:
• What is the role of niacin and riboflavin in energy
metabolism
Niacin (vit B3) : NAD
Riboflavin: FAD
• What does oxidation and reduction mean?
Oxidation: loss of electrons
Reduction: gain of electrons
OILRIG
• What is the role of niacin and riboflavin in energy
metabolism
Niacin (vit B3) : NAD (niacin functions are co- enzyme)
Riboflavin: FAD
assist dehydrogenase enzyme in transferring the hydrogen all along ETC
• How are glucose, triglycerides, amino acids and
ethanol converted to ATP? Explain the pathway for
each macronutrient in dot points, naming the key steps
with substrate and product
Glucose:
aerobic (glycolisis- pyruvate Acetyl CoA- citric acid cycle- ETC) (32 ATP)
anaerobic (glycolysis- pyruvate- lactic acid) (2 ATP)
Fats:
lipolysis– Beta oxidation– acetyl CoA– CAC- ETC
1 16C carbon= 106 ATP
protein:
??
amino acids:
alcohol: 1. MEOS 2. catalase 3. alcohol dehydrogenase
• Define ketogenesis, ketosis, ketoacidosis, ketolysis
Ketogenesis: formation of ketone bodies
ketosis: raised levels of ketone bodies in the body tissues which is typically when the body doesnt have enough glucose to burn.
ketoacidosis: pancreas is damaged, no insulin produced- rely only on fatty acids- metabolic state- v high concentrations of ketone bodies - lowers body pH.
ketolysis: reutilisation of ketone bodies.
• Where are ketone bodies (KB) formed?
in the liver by breakdown of excess fatty acids
fuel for heart, brain and muscle.
• How are KB formed?
from the breakdown of fatty acids- occurs in metabolic environment where fat is primary source of E.
• Where are KB used?
extra hepatic tissue only- brain, muscles and heart.
• In what conditions are KB formed?
metabolic environment where fat is the primary source of E
• Describe the pathway of gluconeogenesis. Can typical
fatty acids be used as substrate for gluconeogenesis?
Why? Why not?
gluconeogenesis- forming new glucose from glycogenic amino acids carbon skeleton (oxaloacetate).
no they can’t- transformed- Not the same carbons-
( from lactic acid (cori cycle) and amino acids)
neo- new
genesis- generating
gluco- glucose
glycogenolysis- glycogen— glucose
gly- glycogen
lysis- break down.
• How is ATP produced during fasting (from a few hours to a few days of fast)
- hepatic glycogen breakdown
- muscle glycogen
- protein breakdown
- fat breakdown
- ketogenesis: ketone bodies.
• What takes place during prolonged fasting to spare
lean body mass? Explain your answer comprehensively
ketogenesis: ketone body production (fat stores from adipose tissue)
• What are the 6 factors, and their role, regulating energy metabolism?
- liver
- substrates
- ATP concentrations- “status’
- functioning enzymes
- Hormones
- presence of vitamins and minerals.
protects the stomach lining
Mucus
promotes HCL secretion
Gastrin (hormone) (G - cells)
emulsifies fat
Bile
neutralises gastric juice activity
Bicarbonate