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NWHSU Biochem 1 T1
NWHSU Biochem 1 Clicker questions for Test 1 not incl Quiz 1 Q's
Question | Answer |
---|---|
The three-dimensinal structure of macromolecules is formed and maintained primarily through noncovalent interactions. Which one of the following is NOT considered a weak interaction? A. carbon-carbon bonds B.hydrogen bonds C.hydrophobic D.ionic E.VanderW | carbon-carbon bonds |
is/are covalent stabilizing force (s) in the tertiary/quaternary structure of many proteins. A.Hydrogen bonding B.Disulfide bonds C.Hydrophobic interactions D.Ionic interactions E.Van der Waals interactions | Disulfide bonds |
The main stabilizing force in Beta sheets is A.ionic bonding B.hydrophobic interaction C.hydrogen-bonding D.Van der Waals interaction | Hydrogen-bonding |
The main stabilizing force in Alpha Helix's is A.ionic bonding B.hydrophobic interaction C.hydrogen-bonding D.Van der Waals interaction | Hydrogen-bonding |
What is the first enzymatic modification in Collagen Biosynthesis? | Hydroxylation (attachment of OH) |
What does Hydroxylation attach to protein chain? | OH Group is substituted for H (Hydroxylation is dependent on Vitamin C) |
What amino acid is atypical for proteins but collagen's ribosomes use regularly to assemble collagen? | Proline (most common sequence of collagen are Glycine-Proline-X, and Glycine-X-Hydroxyproline) |
What hydroxylated amino acids are necessary for cross-linking of the triple helices to form triple helix structure? | Hydroxylation transforms relative amino acids to Hydroxyproline and Hydroxylysine |
What is the second enzymatic modification in Collagen Biosynthesis? | Glycosylation (attachment of carbohydrates at the OH site) |
What is the third enzymatic modification in Collagen Biosynthesis (which takes place in the Golgi Apparatus)? | Formation of Disulfide bonds in triple helix formed by three Proline Alpha chains |
When biosynthesizing collagen, what is released in to the extracellular space via a Golgi Vesicle? | Procollagen |
What is the fourth enzymatic modification in Collagen Biosynthesis (which takes place in the extracellular space)? | removal of C and N terminal sequences |
Besides Disulfide bonds, what are some additional stabilizing force (s) in the tertiary/quaternary structure of many proteins. A.Hydrogen bonding B.Covalent bonds C.Hydrophobic interactions D.Ionic interactions E.Van der Waals interactions | Hydrogen bonding |
The vitamin C-dependent modification step in collagen synthesis is A.translation B.hydroxylation C.glycosylation D.cystine formation E.cleaving of C-termini | Hydroxylation |
The cleaving of the N- and C-terminal sequences to form tropocollagen occurs in the 1.Endoplasmic Reticulum 2.Cytoplasm 3.Golgi Vesicles 5.extracellular space | extracellular space |
Hemoglobin is mainly located in A.muscle tissue B. the lungs C.white blood cells D.red blood cells E.the serum | red blood cells |
What amino acid allows for tight winding of the Collagen's triple helix structure A.Tryptophan B. Valine C. Proline D.Glycine | Glycine |
Myoglobin is mainly located in A.muscle tissue B.the lungs C.white blood cells D.red blood cells E.the serum | muscle tissue (Myoglobin stores Oxygen in tissue) |
is a prosthetic group of hemoglobin. A.Histidine B.Heme C.CO D.O2 E.Myoglobin | Heme |
A ligand is A. bound non specifically by its protein B. a chemical species that is reversibly bound to its protein C. always covalently bound to its protein D. always a polypeptide E. always of a complex molecular structure | a chemical species that is reversibly bound to its protein |
Binding of a ligand leading to a change of affinity at another binding site of the protein, changing the conformation of polypeptide conformation; is called what? | allosteric effect |
The heme prosthetic group of hemoglobin consists of a pyrrol-ring system with ____bound in its center. A. Fe2+ B. Fe3+ C. NO D. CO E. nothing | Fe2+ |
____is a ligand of hemoglobin. A. Fe2+ B. Heme C. Porphyrine D. O2 E. Myoglobin | O2 |
What allosteric effector increases the sigmoid effect on hemoglobin's affinity for oxygen? | BPG (=DPG, 2,3-di or bisphosphoglycerate |
High altitude or Low oxygen for hours (12-24)will encourage ? in red blood cells to bind to the effector sites, reduce hemoglobin's affinity for oxygen, releasing oxygen to tissues over days (1-2 days), and increases red blood cell count over weeks (3=+) | BPG |
With the Bohr effect, as PH goes up, oxygen affinity goes ? | up |
C6H12O6 (glucose) + 6O2 = 6H2O + ? into solution, (respiration and PH) | 6CO2 (six carbon dioxides) |
What stabilizes the PH in blood? | 1. Buffers inside blood and serum 2. 30% of CO2 carried by Hb 3. 10% carried to lungs as is |
CO2 up in tissues but down in lungs, in tissues PH goes ?, Oxygen affinity goes ? | down, down |
What is different about Fetal Hemoglobin? | No binding site for BPG because the amino acid sequence is slightly different (w/in 120 days HbFetal substitutes out for HbAdult) |
Myoglobin shows a(n) ______binding curve. A. Linear B. Hyperbolic C. Exponential D. Sigmoid | Hyperbolic |
BPG plays a role in adaptation of the human body to lower p)2 at higher altitudes by A.lowering the partial pressure of O2 in the tissue B.competitively binding to the heme-Fe2+ C.allosteric D.converting Fe2+ to Fe3+ | allosteric, binding to an allosteric binding site on the hemoglobin and lowering hemoglobin's affinity for O2 |
Fe2+ is protected from ____by surrounding nitrogen atoms in the pyrrole ring structure of heme and a nitrogen atom of a histidine.A. deprotonation B. chelation C. oxidation D. reduction E. protonation | oxidation |
The mutation behind sickle cell anemia leads to the replacement of ___by _____in subunity Beta. which combination? hydrophilic/phobic glu; hydrophilic/phobic val | hydrophilic glu; hydrophobic val |