Biochem Flashcards
Define carbohydrate
Optically active polyhydroxy aldehyde/ketone or compounds that yield them on hydrolysis
What is the ratio of C,H and O in carbohydrates?
1:2:1
What are monosaccharides?
They are the building blocks of polysaccharides or carbohydrates.
They contain 1 aldehyde/ketone group and 2 or more hydroxy groups
Examples of monosaccharides
Glucose, galactose, fructose
Which compound is considered as the reference carbohydrate?
Glyceraldehyde (C3H6O3)
What are oligosaccharides?
They are compounds which yield 2-10 monosaccharides on hydrolysis
Further divided into Disaccharides, Trisaccharides, Tetrasaccharides and Pentasaccharides
What is the other name of Monosaccharides?
Simple sugar
Examples of Disaccharides
Lactose, Sucrose, Maltose, Gentiobiose and Trehalose
Examples of Trisaccharides
Rhamniose, Gentianose, Raffinose
Examples of Tetrasaccharide
Stachyose, Scorodose
Example of Pentasaccharide
Verbascose
General formula of monosaccharides
Cn(H2n)On
General formula of disaccharides
Cn(H2O)n-1
General formula of Trisaccharides
Cn(H20)n-2
General formula of Polysaccharides
(C6 H10 O5)x
Composition of sucrose
Alpha D-glucose and Beta D-fructose
Composition of maltose
2 (alpha D-glucose)
Composition of lactose
Beta D-glucose + beta D-galactose
Name the essential amino acids
Methionine, Threonine, Tryptophan, Valine, Leucine, Isoleucine, Histidine, Arginine, Phenylalanine
Name the Non-essential AA
Glycine, Alanine, Serine, Cysteine, Tyrosine, Proline, Aspartic acid, Glutamic acid
What are the Semi-essential AA
Histidine and Arginine
Name a Non-protein AA
Ornithine
What AAs can Glycine be synthesized from?
Serine, Threonine, Betaine
What are the reactants for the synthesis of Alanine?
Pyruvate and Glutamate
What water soluble vitamin is absent in eggs?
Vitamin C
Pulses are deficient in what AA?
Methionine
Which vitamin is required by dopamine beta-hydroxylase for the conversion of Dopamine to Nor-epinephrine?
Vitamin C
Which AA is the precursor of Meltonin?
Tryptophan
Technique for the purification of proteins
Affinity chromatography
What is the Cori cycle for?
Synthesis and re-use of Glucose
In which condition is Glucose tolerance decreased?
Diabetes mellitus
Generally how many AAs do all proteins contain?
More than 50
Name some reducing sugars
Glucose, Fructose, Maltose, Lactose
Name some Non-reducing sugars
Sucrose, Glycogen, Inulin
Parts of Rhodopsin
Opsin and 11-cis Retinal
What is Rhodopsin?
A light sensitive protein in retina that enables vision in low light
Which is the non-protein part of Rhodopsin?
Retinal
What ring does the molecule of Vitamin A1 contain?
Beta carotene ring
Vitamin K3 is also called
Menadione
Composition of Folic acid
Pteridine + para amino benzoic acid + Glutamic acid
Which test is used for the determination of an amino acid sequence?
Sanger reagent
Which test is used to identify the deficiency of Pyridoxal (B6)
Xanthurenic acid test
1 IU of Vit D = the biological activity of…
0.025 microgram of cholecalciferol
In what ph is the absorption is Vit D increased?
Acidic pH of the intestine
By what enzyme is beta carotene oxidatively cleaved by?
Beta carotene dioxygenase
Which test is used to evaluate the detoxifying function of liver?
Hippuric acid test
Xanthoprotic test is positive for…
Aromatic AA
What kind of an enzyme is Xymogen?
An inactivated enzyme
Vit B1
Thiamine
Vit B2
Riboflavin
Vit B3
Niacin
Vit B5
Pantothenic acid
Vit B6
Pyridoxine, pyridoxal
Vit B7
Biotin
Vit B9
Folic acid
Vit B12
Cobalamin
What is Entropy?
Degree of randomness or disorder of a system
Directly proportional to spontaneity
Denoted by S
What is Enthalpy?
Heat content of a system
Denoted by H
Gibb’s Free energy
Denoted by G
Delta G = delta H - T(delta)S
Here, H has to be -ve and S has to be +ve
What are Energy Rich Compounds?
Compounds which release atleast or more than 7cal/mol energy at pH=7
They are also called energy rich phosphates
What is Zellweger syndrome?
The most severe peroxisome biosynthesis disorder.
It is caused by the absence of functional peroxisomes and other organelles
What is meant by Stereoisomerism?
Same molecular formula, different structures
What is meant by an Epimer?
Two monosaccharides that differ from each other around a single specific C atom
Eg: D-galactose and D-glucose (around C-4)
What is meant by an anomeric carbon?
The carbonyl carbon on the open ended chain form of a sugar
What are Enantiomers?
Mirror images of 2 sugar molecules
Eg: D-glucose and L-glucose
What is meant by Tautomerism?
Shifting of a H atom from 1 carbon to another to form “enediols”
How do you determine D and L forms of a sugar?
By locating the H and OH of the Carbon atoms next to the primary alcohol
A. If OH is on the right - DEXTRO
B. If OH is on the left - LEVO
What is Sucrose also called?
Cane sugar
What are the breakdown products of Starch called?
Dextrins
What is Lobry de Bryn-von Ekenstein transformation?
The process where are sugar containing an anomeric carbon undergoes tautomerisation in alkaline solutions
Eg: When glucose is kept in an alkaline solution for several hours, it undergoes transformation to give fructose and mannose
What are diastereomers?
Stereoisomers that are not mirror images of each other
Which vitamin is also called “Sterility vitamin”?
Vit E
What base does Thymine have?
Pyrimidine base
What is the IUPAC name of Calcitriol?
1,25 - dihydroxy cholecalciferol
Which vitamin serves as a respiratory catalyst?
Vit B2 (Riboflavin)
What are Pro-enzymes?
Enzymes produced in their inactive form in living cells
Which vitamin is the co-enzyme for FMN (Flavin mono nucleotide)?
Vit B2
Specificity of an enzyme is mostly dependant on…
Pyruvate and Apo-enzymes
How many molecules of ATP does one molecule of Palmitate produce?
129 ATP
Which vitamin promotes Glucose absorption?
Vit B1
Which AA is also used as an anti-biotic?
Azaserine
Which vitamin is the Pellagra preventive factor of Goldberg?
Vit B3 (Niacin)
Adenylate cyclase is activated by…
Glucagon
Which vitamin is Co-enzyme A derived from?
Vit B5
Who proposed the “lock and key” theory?
Emilia Fisher
Name the allosteric inhibitor or Hexokinase
Glucose - 6 - phosphate
What is the composition of Barfoed’s reagent?
Cu acetate and glacial acetic acid
Other name of Glycolysis
Embden Mayerhoff pathway
What is Von-Girke’s disease caused due to?
The deficiency of G-6-P
Leads to an enlarged liver due to excess storage
What is Pompe’s disease caused due to?
The deficiency of acid maltase
Which disease is Glycogen storage disease (GSD-I)?
Von-Girke’s disease
What is Cori’s disease caused due to?
The deficiency of de-branching enzymes
What is Anderson’s disease caused due to?
Due to the deficiency of de-branching enzymes
There is production of an abnormal form of Amylopectin, which accumulates in heart and liver
What is McArdle’s disease caused due to?
The deficiency of muscle phosphorylase
What is Her’s disease caused due to?
The deficiency of liver phosphorylase
Which disease is GSD (Glycogen storage disease) IV?
Anderson’s disease
Which disease is GSD II?
Pompe’s disease
Which disease is GSD III?
Cori’s disease
Which disease is GSD V?
McArdle’s disease
Which disease is GSD VI?
Her’s disease
What is the normal amount of ketone bodies in blood?
Less than 1mg/dL
What are the 3 main ketone bodies that are synthesized in the body?
Acetone, Acetoacetate and beta-hydroxy butyrate
Name the 1° ketone bodies
Acetoacetate
Name the 2° ketone bodies
Acetone and beta-hydroxy butyrate
By what test is the presence of ketone bodies detected in urine?
Rothera’s test
The test is only for Acetone and Acetoacetate
By what test is the presence of Beta-hydroxy butyrate detected in urine?
Modified Rothera’s test
Special test for Acetoacetate
Gerhard FeCl3 test
During which conditions is the production of ketone bodies sorted to, by the body?
- During starvation
- During uncontrolled DM
Why is Acetoacetate called a 1° ketone body?
Because acetone and beta hydroxy butyrate is synthesized from Acetoacetate
Name the major substrates used for Gluconeogenisis
- Pyruvate
- Intermediates from Kreb’s cycle
- Lactate
- Glycerol
- Propionate
- Glucogenic AA
What is the inhibition of Glycolysis by O2 called?
Pasteur effect
In TCA cycle, Citrate synthase is inhibited by what enzyme?
Succinyl CoA
The enzymes of TCA cycle are located in…
Mitochondrial matrix
Uronix acid pathway is concerned with the synthesis of which vitamin?
Vitamin C
As per IUB, the unit for enzyme activity is expressed in….
Katal
Which amino acid has the presence of an Indole ring?
Tryptophan
Which deficiency leads to Gaucher’s disease?
Beta-glucosidase deficiency
What is the protein part of Lipoprotein called?
Apoprotein
According to Fredreickson’s classification of Cholestremia, type IV Hypercholestremia is caused due to….
Inc. Level of VLDL
What percent of HDL is composed for triacylglycerol?
88%
What are the 2 products of beta oxidation of odd chain fatty acids?
Propionyl CoA + Acetyl CoA
In Z-DNA, how many base pairs are present in each turn of DNA?
12
What percent of RNA is composed of ribosomes RNA?
50-80%
What is the function of rRNA?
To provide structural framework to ribosomes
Oxidative amination takes place mostly in…
Liver and kidney
In transamination process, all transaminases require ______co-enzyme
PLP co-enzyme
Tocopherols prevent the oxdn of which vitamin?
Vitamin A
Name the amino acids required for the synthesis of Creatinine
Glycine, Arginine and Methionine
Hypervitaminosis of Vitamin A causes
Dermatitis and loss of hair
Storehouse of NH3 in the biological system
Glutamine
Lesch-Nyhan syndrome is caused due to the deficiency of…
HGPRT
Orotic acidurea can be treated with a diet rich in…
Guanine
Menke’s disease is caused due to the deficiency of….
Copper
Precursor of Melanine
Tyrosine
Hyperlipoproteinemia type III is caused due to elevated levels of…
Intermediate density lipoprotein (IDL)
Jamaican vomiting disease is caused due to deficiency of ….
Hypoglycin A
Krabbe’s disease is caused due to a defect in…
Beta galactosidase
Name a drug that causes the inhibition of Aconitase in TCA cycle
Flouroacetate
The deficiency of which enzyme leads to Cori’s disease?
Amylo alpha - 1,6 - glucosidase
Name the starting materials of retinol
Beta-iodine and methyl vinyl lactone
Name the starting materials of Vit B5
Formaldehyde and iso-butyryladehyde
What kind of a fatty acid is Palmitic acid?
Poly unsaturated and essential
How is the NH3 produced during the muscle degeneration of nitrogenated compounds transported in blood?
They are transported via ALANINE and GLUTAMINE as carriers
What AA do Nitrous oxide and Urea have in common as an intermediate precursor?
Arginine
How is the correct conformation of complex proteins formed?
With the help of CHAPERONES that help in protein folding
Which cell does IgD have as a major function?
B-cell receptor
Starting material of B7 (Biotin)
Dibenzyl succinic acid
Starting material of Ascorbic acid
Ribose
The deficiency of which enzyme causes Porphyria cutanaetarda?
Uro-porphyrinogen decarboxylase
What is Porphyria cutanaetarda?
Porphyria is a group of rare genetic disorders that affect the skin and nervous system
The above mentioned disease is the most common type of Porphyria.
What is the P:O ratio of FADH2
2
Which sulfer containing compound is involved in decarboxylation reaction?
Lipoic acid
Which vitamin is termed as the “Vitamin in search of diseases”?
Vitamin E
Wenicke-Korsakoff is a disease that is caused due to the deficiency of….
Vitamin B1
Which vitamin decreases the circulation of free fatty acids in adipose tissue?
Niacin
Which one of the Vitamin Bs is synthesized by microorganisms?
B12
Which kind of protein gives Biuret test?
A protein that contains 2 or more peptide linkages
Which high energy phosphate inhibits Isocitrate dehydrogenase in TCA cycle?
ATP
The level of which enzyme is elevated during Muscular dystrophy?
Aldolase
What is the indication of Wilson’s disease in a person?
Increased level of G-6-PD
What colour does Iodopsin give in the visual cycle?
Green
Chemical formula of Capryllic acid
CH3 - (CH2)⁶ - COOH
Examples for Simple lipids
Lipids, Waxes and Oils
Examples for Compound Lipids
Phospholipids
Glycolipids
Lipoproteins
Examples of Derived lipids
Steroids and Carotenoids
What are Simple lipids composed of?
Esters of fatty acids and alcohol
Composition of Compound lipids
Esters of fatty acids and alcohols containing groups like PO4, sugars, etc
Composition of Fats and Oils
Esters of fatty acids and glycerol
Composition of Waxes
Esters of fatty acids and alcohol, OTHER THAN GLYCEROL
How are Derived lipids made?
By combining simple and compound lipids by hydrolysis
THEY DO NOT RESEMBLE FATS IN STRUCTURE
What are the 3 main components of a Nucleotide?
Pentose sugar + Nitrogenous base + Posphate group
What are the types of Pentose sugar?
Ribose and Deoxy Ribose sugar
What is the difference between Nucleotide and Nucleoside?
Nucleoside does not contain PO4 group
What bond is present between a Pentose sugar and a Nitrogenous base?
Glycosidic bond
Bond present between a Pentose sugar and a PO4 group
Phosphodiester bond
What does the 2nd law of Thermodynamics state?
“All spontaneous processes inc the ENTROPY of the process”
What is the 1st law of Thermodynamics?
The 1st law is called the ‘Principle of Conservation of Energy’
Energy can neither be destroyed nor be created. It can only be converted from one form to another
