BIOL 111 Flashcards
What do you call a monosaccharide with an aldehyde and what do you call one with a ketone
aldose and ketose
What do you call a monosaccharide with 3 carbons
triose
what side does the OH group sit on the D isomer
Right side
What is the relationship between number of chiral atoms and optical isomers
2^n
What does ketones and aldehydes reacting with hydroxyl groups mean for monosaccharides
It means they can form cyclic structures
Where is the anomeric caron for ketones and where is it for aldehydes
C-2 for ketones and C-1 for aldehydes
Name the two regions of a fatty acid
Carboxyl head group and hydrocarbon tail
what is the difference between the two regions of a fatty acid
Tail is hydrophobic and head is hydrophillic so they are amphipathic (two different chem characteristics)
What are the different suffixes for saturated, monounsaturated and polyunsaturated fatty acids
Saturated = anoic, monounsaturated = enoic
polyunsaturated = di/tri ect + enoic
what prefixes do you use for unsaturated fatty acid naming
cis and trans (can be multiple e.g cis,cis,trans-9,12,14-octadeca…)
Where do you start counting carbons on a fatty acid
at the carboxyl carbon
Why can’t animals synthesise fatty acids beyond carbon 9
They do not have the desaturase enzyme
what are essential fatty acids
unsaturated fatty acids that are needed but cannot be synthesised by animals
What are good sources of essential fatty acids
fish oils (eat microalgae) and plant based spreads (e.g flora)
What are the differences between neutral lipids and polar lipids
neutral lipids are energy stores whereas polar lipids have structural roles (e.g cell membranes)
What is the important feature of triglycerides
It is an efficient energy store (more so than carbohydrates)
Why do polyunsaturated fats have lower melting points
They can’t pack as tightly together and have more fluidity
What differences in structure do cis and trans fats have
trans double bonds do not cause a bend like cis so they do not effect melting point and are implicated in circulatory diseases (naturally occuring fats are usually cis)
how are phosphoglycerides composed
Two fatty acids attatched to a glycerol and a phosphate attatched to the other side of the glycerol with a variable group on the phosphate
Why are membranes important
1) Seperate cell contents from surroundings
2) Maintain different envirnoments inside and outside membrane (organelles)
3) Selectively permeable
How do phopspholipids move in the membrane
They move laterally rapidly (roughly 2um/s) but very rarely flip-flop their orientation
What affects membrane fluidity
1) cholesterol acts as temperature buffer
2) more unsaturated fatty acids prevent packing increasing membrane fluidity and vice versa
What affects protein movement in natural membranes
The cells actin cytoskeleton essentially fences the proteins in limiting their movement unless they rarely “hop” into another area
What function do glycoproteins and glycolipids have
They act as tags for cell regognition (recognised by receptor proteins)
