Dietary, fat, protein, & carbs

Question 1

What are the 3 dietary macronutrients?

Answer 1

fats
proteins
carbs

Question 2

What are lipids soluble and poorly soluble in?

Answer 2

soluble in organic solvents

poorly soluble in water

Question 3

Name the 6 functions of fat

Answer 3

fuel & energy store
insulation
protection 
membrane structures
intra/intercellular signalling
substrate for hormone & prostaglandin synthesis

Question 4

What are triglycerides made up of?

Answer 4

glycerol and 3 fatty acids

Question 5

What 3 things can the fatty acid chain of a triglyceride be? and which are double bonded?

Answer 5

saturated (no double bonds)
monounsaturated (1 double bond)
polyunsaturated (more than one double bond)

Question 6

Which are more unsaturated oils or fats?

Answer 6

oils

Question 7

What are fats and oils derived from?

Answer 7

fats - animals

oils - fish or plants

Question 8

Where are the double bonds located in omega 3 & 6?

Answer 8

3 - 1st double bond 3 carbons from methyl terminal

6 “ 6 “

Question 9

What are sterols precursors to?

Answer 9

bile slats

Question 10

Where are sterols found?

Answer 10

in animal fats

Question 11

Why are essential fatty acids needed for humans?

Answer 11

can’t insert double bond between 1st seven carbons of fatty acids and required for prostaglandins and leukotrienes

Question 12

What is linoleic & a- linoleic and how much is needed to prevent deficiency?

Answer 12

lino - omega 6 (1%)

a- lino - omega 3 (0.2%)

Question 13

Where is cholesterol found in the body?

Answer 13

cell membranes

Question 14

What synthesis pathways is cholesterol a substrate for?

Answer 14

bile acids
steroid hormones
vit d

Question 15

What are cholesterol and triacylglcerides (TAGs) transported around the body as?

Answer 15

lipoproteins

Question 16

VLDLs are rich in what? and transported to where?

Answer 16

rich in TAGs and transported to adipose/ muscle

Question 17

LDLs are rich in what and transported from where to what?

Answer 17

rich - cholesterol

transports cholesterol from liver to cells

Question 18

HDLs do what?

Answer 18

removal of excess cholesterol from peripheral tissues

Question 19

How does raised LDL cholesterol cause atherosclerosis?

Answer 19

taken up by macrophages to foam cells these accumulate in blood vessel walls

Question 20

What is surplus carbs stored as and where?

Answer 20

glycogen and in liver

Question 21

What is NSP?

Answer 21

non starch polysaccharides (fibre)

Question 22

What do insoluble NSPs do?

Answer 22

attract water, soften stools, increase faeces bulk and reduce transit time in GIT

Question 23

What do soluble NSPs do?

Answer 23

ferment in colon, blunts postprandial glucose response by slowing digestion, binds to bile salts, decrease cholesterol re-uptake

Question 24

What are the 3 physiological actions of NSP?

Answer 24

substrate for bacterial fermentation in colon

1) bacteria produce short chain fatty acids absorbed by colonic mucosa
2) bacteria produce butyric acid, important fuel for mucosal cells of colon
3) faecal bulk

Question 25

What is glycemic index?

Answer 25

relates the concentration of glucose in the plasma after consumption of food