Lipids - 3.5 - (5) Flashcards
Page 57
How can lipids be identified in the laboratory?
by the emulsion test
Emulsion test - What occurs first?
the sample is mixed with ethanol
Emulsion test - What happens to the resulting solution?
it is then mixed with water and shaken
Emulsion test - If a white emulsion forms as a layer on top of the solution, what does this indicate?
this indicates the presence of a lipid
Emulsion test - If the solution remains clear, what does this show?
that the test is negative and the absence of the lipid
What is constantly changing?
health advice
Why is it that health advice can be confusing?
because the way that new advice is issued in the media from new research
What has not usually been evaluated?
the validity of the research and the science is also not easy to explain
As majority of the general public do not have scientific backgrounds, what are they not aware of?
the nature of scientific understanding
What is constantly changing and why?
scientific knowledge as technology develops so our understanding of biological processes increases
What is it difficult to isolate the effect of?
of just one nutrient and it is now believed that nutrients don’t work in isolation but as part of the combined effect of a whole range of nutrients
What is this called?
food synergy
What are whole grains believed to have a greater effect than?
any of their individual components
Which combination helps to prevent certain types of heart disease?
fish, fruit, and vegetables
What is often flawed and why?
the data used in reports as the subjects involved in studies do not usually provide accurate information
What do people tend to underestimate?
what they eat, they forget what they have eaten and don’t know the exact ingredients of meals, especially if they are eating out
How are people different?
due to their genetic makeup and so, they respond differently to different nutrients
What do studies that catch the headlines often involve?
small numbers of subjects and these inherent differences change the findings
How are the resulting headlines?
they can be eye-catching, but not very accurate
What are the studies often contradicted by?
the next study
