facil Flashcards
What metabolites of arachidonic acid are there? How does aspirin work?
Precursor of prostaglandins, prostacyclin, thromboxanes, leukotrienes and endocannabinoids
Aspirin (acetylsalicylic acid, ASA) works by inhibiting prostaglandin synthesis and is therefore
anticoagulant, anti-inflammatory, antipyretic and analgesic.
Which glycerolipids do you know? (Overview of structure and synthesis)
Glycerolipids are lipids with glycerol as their basic structure
phosphoglycerides
glycoglycerides: glycero is linked to two fatty acid residues and one phosphoric acid residue .l + one or two fatty acids + a mono- or oligosaccharide)
ÿ Phosphate residue, glycerin residue & fatty acids
Important membrane phosphoglycerides:
ÿ Phosphatidylserine
ÿ Phosphatidylcholine
How is glycogen structured and which enzymes are needed to break down and build up glycogen?
central protein = glycogenin, to which up to 50,000 glucose building blocks are attached and
connected via an ÿ-1,4-glycosidic bond, branches are bound via ÿ-1,6-glycosidic bond
ÿ Structure by glycogen synthase, branching enzyme
ÿ Degradation by phosphorylase, transferase, alpha-1,6-glucosidase
Which glycolysis reactions must be avoided in gluconeogenesis and what is the cost of
synthesizing glucose from pyruvate?
- Hexokinase (Glucose-6-Phosphatase)
- Phosphofructokinase I (Fructose-1,6-Bisphosphatase)
- Pyruvate kinase (through phosphoenolpyruvate carboxykinase)
4 atp, 2 gtp, 2nadh
What is the function of the glucose-alanine cycle?
enzima
ÿ The glucose-alanine cycle serves to transport toxic ammonia from the muscle to the liver.
piruvato->alanina->piruvato-> glucosa-> iruvato
alanine aminotransferase
What is the function of glutamate dehydrogenase? (+ reaction)
+ ÿ Glutamate is converted by glutamate dehydrogenase to ÿ-ketoglutarate and NH4
It is important for the fixation or release of ammonium (NH4+ ), which is later bound to urea in the urea cycle in order to be excreted
General reaction of aminotransferases? Which coenzyme? Example
alanina+ alfaketoglutarato= piruvato+ glutamato
All aminotransferases have pyridoxal phosphate (PLP) as a coenzyme, which is derived from pyridoxine (vitamin B6).