Biochemistry Flashcards
About simple lipids we can say:
a) They contain glucose bound by ester bond.
b) They do not contain ester bond.
c) They have hydrophobic properties.
d) They are esters of long-chain fatty acids and glycerol.
c) They have hydrophobic properties.
d) They are esters of long-chain fatty acids and glycerol.
Esters of long-chain fatty acids and glycerole:
a) are cleaved in gastrointestinal tract by lipase
b) occur in esters of cholesterol
c) occur also in complex lipids
d) are part of steroids
a) are cleaved in gastrointestinal tract by lipase
c) occur also in complex lipids
Alcylglycerols in their molecule can contain components bound:
a) by the phosphoester bond
b) saturated fatty acids and glycerol
c) unsaturated fatty acids and glycerol
d) glucose
b) saturated fatty acids and glycerol
c) unsaturated fatty acids and glycerol
Complex lipids are:
a) phospholipids
b) triacylglycerols with different types of carboxylic acids
c) waxes
d) those lipids which are the main components of adipose tissue
a) phospholipids
Fatty acids are:
a) amphiphatic
b) equipped with a N- and a C-terminus
c) made by the enzyme fatty-acid-synthase
d) main component of waxes
a) amphiphatic
c) made by the enzyme fatty-acid-synthase
d) main component of waxes
In phospholipids:
a) saturated fatty acids are not present
b) glycerol, fatty acids, phosphoric acid and nitrogenous component e.g. choline are present
c) part of molecule is electrically charged (dipole)
d) one part of molecule is hydrophilic and the other is
hydrophobic
b) glycerol, fatty acids, phosphoric acid and nitrogenous component e.g. choline are present
c) part of molecule is electrically charged (dipole)
d) one part of molecule is hydrophilic and the other is
hydrophobic
Steroids:
a) belong to complex lipids
b) can be found in cell membrane
c) are the energy storage form of lipids
d) some of them are hormones
b) can be found in cell membrane
d) some of them are hormones
Isoprene unit:
a) is building unit of terpenes
b) has the formula – (C5H8)n
c) has the formula -(CH2-CH=CH-CH2)
d) is derived from 2-metyl-1,3butadiene
a) is building unit of terpenes
b) has the formula – (C5H8)n
d) is derived from 2-metyl-1,3butadiene
Osmotic lysis of cell occurs:
a) when excess water moves into the cell causing its volume to increase and finally it bursts
b) when an animal cell is placed into distilled water
c) when the cell absorbs water and decreases
d) when an animal cell is placed into a hypertonic environment
a) when excess water moves into the cell causing its volume to increase and finally it bursts
b) when an animal cell is placed into distilled water
Sort the following compounds by increasing membrane permeability:
a) ethanol
b) N2
c) H2O
d) Ca2+
- Ca2+
- H2O
- ethanol
- N2
General formula C6H12O6 refers to:
a) glucose
b) arabinose
c) ribose
d) mannose
a) glucose
d) mannose
Fructose is:
a) compound soluble in polar solvents
b) polyhydroxyaldehyde
c) polyhydroxyketone
d) substrate for synthesis of saccharose
a) compound soluble in polar solvents
c) polyhydroxyketone
d) substrate for synthesis of saccharose
Ring structure with one O-atom and 4 C-atoms. Two C-atoms have one OH group. One C-atom left to the O-atom has CH2OH. One C-atom right to the O-atom has CH2OH and OH.
a) glucose
b) fructose
c) pyranose
d) furanose
b) fructose
d) furanose
Cyclic form of monosaccharides is:
a) ester
b) acetal
c) hemiacetal
d) part of steroids
c) hemiacetal
Benedict’s reagent is a chemical solution that is taken for the detection of:
a) aldoses
b) ketoses
c) glycogen production
d) glucosuria
a) aldoses
d) glucosuria
Glycogen is:
a) is branched
b) animal version of starch
c) consists of glucoses
d) contains 1,4- and 1,6-glycosidic bonds
a) is branched
b) animal version of starch
c) consists of glucoses
d) contains 1,4- and 1,6-glycosidic bonds
Molecule of starch is formed:
a) by esterification
b) by polycondensation
c) by phosphorylation
d) by hydrolysis
b) by polycondensation
β-O-glycosidic bond is present in molecule of:
a) mannose
b) cellulose
c) starch
d) maltose
b) cellulose
In living systems saccharides can be covalently linked to:
a) nucleic acids
b) lipids
c) proteins
d) none of the molecules listed above
b) lipids
c) proteins
General formula (C6 H10 O5)n refers to:
a) aldopentoses
b) lactose
c) disaccharides
d) starch
d) starch
Basic building units of proteins are connected by bond:
a) which is not cleaved by denaturation
b) which belongs to covalent bonds
c) hydrogen
d) disulphide
a) which is not cleaved by denaturation
b) which belongs to covalent bonds
Denaturation of proteins can be induced by:
a) proteases
b) changes in pH
c) heat
d) radicals
b) changes in pH
c) heat
d) radicals
Basic building units of proteins are:
a) neutral amino acids, e.g. aspartic acid
b) 2-amino carboxylic acids
c) alpha-amino acids
d) substitution derivatives of carboxylic acids (with –NH2 group bound to alpha carbon atom)
b) 2-amino carboxylic acids
c) alpha-amino acids
d) substitution derivatives of carboxylic acids (with –NH2 group bound to alpha carbon atom)
Important functions of proteins in organisms are:
a) catalysis
b) binding of compounds
c) energy storage
d) providing structure
a) catalysis
b) binding of compounds
d) providing structure
Which amino acid is not proteinogenic:
a) Tryptophane
b) Tyrosin
c) Tyroxine
d) Selenocysteine
c) Tyroxine
Enzymes:
a) are biocatalysts
b) are proteins
c) are macromolecules composed of amino acids connected by ester bond
d) are located always in extracellular space
a) are biocatalysts
b) are proteins
What is responsible for substrate specificity of enzyme reaction:
a) apoenzyme
b) coenzyme
c) pH-optimum
d) decrease of activation energy
a) apoenzyme
c) pH-optimum
Compound A is substrate of enzyme E. Addition of structurally related compound B leads to an increase of Km by 3, while Vmax remains the same. This effect is a(n)
a) allosteric activation
b) non-reversible inhibition
c) non-competitive inhibition
d) competitive inhibition
d) competitive inhibition
Which compound shows a peptide bond:
There are 4 bonds shown, but to be able to answer the question:
What is a peptide bond?
O
I I
C - NH
Which of the following statements about enzymes is/are wrong:
a) enzymes react just with specific substrates
b) enzymes act by lowering activation energy of
substrate
c) enzymes that act in concert are called coenzymes
d) enzymes stabilize transition state of reactants.
c) enzymes that act in concert are called coenzymes
A stepwise oxidation is more favorable than direct burning of sugars in cells, because
a) activation energy is lower;
b) small portions of energy can be easier controlled;
c) released energy can be stored in carrier proteins;
d) energy is released as heat and thus supports other
biochemical reactions ins cell.
a) activation energy is lower;
b) small portions of energy can be easier controlled;
c) released energy can be stored in carrier proteins;
The oxidative degradation of organic substances is known as:
a) catabolism
b) metabolism
c) anabolism
d) reduction
a) catabolism
Oxidation of organic molecules usually results in the release of
a) a hydroxyl ion
b) 2e- and2H+
c) CO2 and H2O
d) Acetyl-CoA
!!! Question in class was: Oxidation of organic molecules usually result in the direct release of!!!
If question with “direct”:
b) 2e- and 2H+
If question without “direct”:
b) 2e- and 2H+
c) CO2 and H2O
Acetyl-CoA is an activated carrier of
a) Phosphate
b) Methyl group
c) Carboxyl group
d) Acetyl group
d) Acetyl group
Glycolysis is the process by which one molecule of glucose is degraded into
a) two molecules of lactat
b) two molecules of pyruvate
c) two molecules of ATP
d) two molecules of 2-oxopropanate
b) two molecules of pyruvate
d) two molecules of 2-oxopropanate
The net energy outcome of glycolysis is
a) 2 acetyl-CoA
b) 2 NADH
c) 2 ATP
d) 2 ATP and 2 NADH
d) 2 ATP and 2 NADH
The net outcome of the citrate-cycle is
a) 3 NADH, 1GTP, 1 FADH2, release of 2 H2O
b) 2NADH and 2ATP
c) 3 NADPH, 1GTP, 1 FADH2, release of 2 CO2
d) 3 NADH, 1GTP, 1 FADH2, release of 2 CO2
d) 3 NADH, 1GTP, 1 FADH2, release of 2 CO2
In ß-oxydation of fatty acids fatty acyl-CoA gets shortened each cycle by how many carbons? a) 1 b) 2 c) 3 d) 4
b) 2
Which equation represents the reaction catalyzed by ATP synthase?
a) ATP –> ADP + Pi + H2O
b) ATP + H2O –> ADP + Pi
c) ADP + Pi –> ATP + H2O
d) ADP + Pi + H2O –> ATP
c) ADP + Pi –> ATP + H2O
Proteins of the respiratory chain are
a) Ubiquinone
b) NADH dehydrogenase
c) Cytochrome c
d) Cytochrome oxidase
a) Ubiquinone
b) NADH dehydrogenase
c) Cytochrome c
d) Cytochrome oxidase
Mitochondria are the organelles in which the following processes occur: a) oxidative phosphorylation b) glycolysis c) citric acid cycle d) ß-oxidation of fatty acids
a) oxidative phosphorylation
c) citric acid cycle
d) ß-oxidation of fatty acids
ATP molecule contains:
a) adenine base
b) macroergic bonds
c) phosphoanhydrid bonds
d) glucose
a) adenine base
b) macroergic bonds
c) phosphoanhydrid bonds
