100% Correct Answers
What is "phyto" greek for? - correct answers Plants
True or False: Phytochemicals are nutritive substances. - correct answers False: Phytochemicals are
generally non-nutritive substances.
What are phytochemicals proposed to contribute to? - correct answers Phytochemicals are proposed to
contribute toward disease prevention
Phytochemicals are ________________________________________ compounds. - correct answers
Phytochemicals are physiologically active compounds.
What are flavonoids? - correct answers A subclass of polyphenols
What is a polyphenol? - correct answers One of the most numerous and ubiquitous groups of plant
metabolites
Polyphenols range from simple phenolic molecules to highly _______________________ compounds
(e.g. tannins) - correct answers Polyphenols range from simple phenolic molecules to highly polymerized
compounds (e.g. tannins)
Why are polyphenols traditionally considered anti-nutrients? - correct answers Due to effects of specific
polyphenols to bind to macromolecules and reduce food digestibility
Plant polyphenols are _______________________________ of plants - correct answers Plant
polyphenols are secondary metabolites of plants
,What is the common structural feature of plant polyphenols? - correct answers There is an aromatic ring
with at least one hydroxyl group
What are the names of the of the two major plant polyphenol synthesis pathways? - correct answers 1.
Shikimate pathway
2. Acetate pathway
What are some reasons (4) plant polyphenols are essential to plant physiology? - correct answers 1.
Contribute to plant morphology (pigmentation)
2. Involved in growth and reproduction of the plant
3. Provide plants with resistance to pathogens and predators
4. Protect crops from plague and pre-harvest seed germination
What are factors that influence the amount of polyphenols in plants? - correct answers - Light
- Genetic factors
- Environmental factors
- Germination
- Degree of ripeness
- Variety
- Processing
- Storage
Explain how light influences the amount of polyphenols - correct answers The highest concentration of
specific polyphenols are in leaves and outer parts of the plants, while only trace amounts are in the
subterranean parts
The presence of polyphenols in foods can increase ______________________ and
______________________. - correct answers The presence of polyphenols in foods can increase
astringency and bitterness
Provide examples of how polyphenols in food contribute to desirable qualities of food. - correct answers
1. Browning of cocoa during processing
,2. Polymerization of tea polyphenols during the manufacturing of black tea
Provide an example of how polyphenols in food contribute to undesirable qualities of food. - correct
answers Enzymatic browning (polyphenol oxidase) and non-enzymatic browning resulting in the
formation of undesirable flavour and colour of fruits and vegetable.
How do phytochemicals in food influence digestibility of nutrients? - correct answers Bind and
precipitate protein, reducing absorption and increasing fecal nitrogen. Tannins for example are
traditionally considered anti-nutrients that interfere with enzymes that can free other macroutrients.
How do phytochemicals in food influence mineral bioavailability? - correct answers Phytochemicals form
complexes with metal cations, interfering with absorption.
How would phytochemicals binding minerals like iron have the potential to be a good thing? - correct
answers If someone has a genetic disorder that causes and increased rate of absorption for minerals like
iron.
The composition of phytochemicals in food can vary widely. Most are ___________________ and
______________________. - correct answers The composition of phytochemcials in food can vary
widely. Most are phenolic and flavonoids.
Why were flavonoids originally named Vitamin P? - correct answers Thought flavonols as vitamins
responsible for pigment.
What vitamin do flavonoids enhance? - correct answers Flavonoids enhance the function of vitamin C,
improving absorption and protecting it from oxidation
Flavonoids are a sub-group of low molecular weight ____________________ substances. - correct
answers Flavonoids are a sub-group of low molecular weight polyphenolic substances.
Where can flavonoids be found? - correct answers They are present in most plants, concentrated in
seeds, fruit skins or peel, bark and flowers
, What is the structure of flavonoids? - correct answers The common structure is diphenylpropanes; 2
aromatic rings linked through 3 carbons (C6-C3-C6)
Which pathway does the A ring of the flavonoid structure arise from? - correct answers The A ring
usually arises from the acetate pathway
Which pathway foes the B ring of the flavonoid structure arise from? - correct answers The B ring usually
arises from the shikimate pathway
What does the C ring tell us about a flavonoid? - correct answers The C ring tells us the major class of
flavonoid.
What are the 6 major classes of flavonoids? - correct answers 1. Flavones
2. Flavonols
3. Flavanones
4. Flavanols
5. Anthocyanidins
6. Isoflavones
Where are flavonoids located in plants? - correct answers Mainly in the leaves, flowers and outer parts
of the plants, decreasing in concentration towards the central core, and only found in trace amounts in
plant parts below the soil surface
Why are there challenges in determining dietary intake of flavonoids? - correct answers There is content
variation depending on a number of factors: species/genetic variation, lighting, environmental
conditions, germination, degree of ripeness, processing and storage.
Why might a cherry tomato contain 6 times more quercitin per gram fresh weight than that of normal
varieties? - correct answers There is more skin being consumed with 1 pound of cherry tomatoes than 1
pound of normal tomatoes and the skin is where the flavonoid quercitin is.
What is contained within the flavonoid database? - correct answers The USDA database contains the
flavonoid content of 500 foods, 28 different flavonoids, but only 5 of the 6 flavonoid subclasses