Q-251. Energy expenditure in resting state depends on
a) Lean body mass
b) Adipose tissue
c) Resting heart rate
d) Exercise
Answer: Lean body mass
Explanation:
Resting energy expenditure and basal metabolic rate are most closely related to the lean body mass which gives an estimate of amount of metabolically active tissue.
Important point:
Adipose tissue is metabolically inert and doesn’t contribute in resting energy expenditure.
Q-252. Which of the following statements about recommended dietary allowances (RDA) is true
a) RDA is statistically defined as two standard deviations (SD) above estimated average requirement (EAR)
b) RDA is defined as being equal to the estimated average requirement (EAR)
c) RDA is defined as being equal to adequate intake (AI)
d) RDA is defined as the recommended minimum requirement
Answer: RDA is statistically defined as two standard deviations (SD) above estimated average requirement (EAR)
Explanation:
Recommended Dietary Allowance (RDA):
The average daily dietary intake level that is sufficient to meet the nutrient requirement of nearly all (97 to 98 percent) healthy individuals in a group
Recommended dietary allowances (RDA) is statistically defined as two standard deviations (SD) above estimated average requirement (EAR).
Important point:
Recommended Dietary Allowance (RDA) is often higher than the recommended minimum requirement.
Q-253. Which of the following plant components is not fermented by gastrointestinal microorganisms?
a) Lignin
b) Cellulose
c) Hemi-cellulose
d) Pectin
Answer: Lignin
Explanation:
Lignin is a non carbohydrate type of dietary fibre that can neither be digested by endogenous enzymes nor fermented by GI microorganism.
Cellulose, hemi-cellulose and pectin are all components that cannot be digested by endogenous enzymes but these components can be fermented by local resident bacteria in GI.
Q-254. A ten year old child with aggressive behavior and poor concentration is brought with presenting complaints of joint pain and reduced urinary output Mother gives history of self mutilation behavior stating that he tends to mutilate his fingers. Which of the following enzymes is likely to be deficient in this child?
a) HGPRTase
b) Adenosine deaminase
c) APRTase
d) Acid maltase
Answer: HGPRTase
Explanation:
Lesch Nyhan Syndrome:
Lesch-Nyhan disease is a genetic disorder associated with 3 major clinical elements: Overproduction of uric acid, neurologic disability, and behavioral problems.
The neurologic disability is dominated by dystonia but may include choreoathetosis, ballismus, spasticity, or hyper-reflexia.
The behavioral problems include intellectual disability (mental retardation) and aggressive and impulsive behaviors.
Patients with the classic disease also develop persistent and severe self-injurious behavior (Self mutilation).
In patients with Lesch-Nyhan disease, uric acid levels in the blood and urine are typically, but not always, increased.
Definitive diagnosis is generally obtained by measurement of the hypoxanthine-guanine phosphoribosyl transferase (HPRT) enzyme. Confirmation of the diagnosis is most reliably made by identification of the HPRT1 gene.
Q-255. All of the following statements about lambda phage are true Except
a) In Lysogenic Phase, it fuses with host chromosome and remains dormant
b) In Lytic Phase it fuses with host chromosome and replicates
c) Both Lytic and Lysogenic Phases occur together
d) In Lytic Phase it causes cell lysis and releases virus particles
Answer: Both Lytic and Lysogenic Phases occur together
Explanation:
Lambda Bacteriophage:
In Lysogenic Phase, it fuses with host chromosome and remains dormant
In Lytic Phase it fuses with host chromosome and replicates
In Lytic Phase it causes cell lysis and releases virus particles
Important point:
Both Lytic and Lysogenic Phases do not occur to gather.
Q-256. Initiation of visual impulse is associated with
a) Condensation of opsin with vitamin-A aldehyde
b) Photo-isomerization and hydrolysis of visual purple
c) Decreased NADP
d) Decreased NAD
Answer: Photo-isomerization and hydrolysis of visual purple
Explanation:
Absorption of light by Rhodopsin (11 Cis Retinal + opsin)-> Isomerization of retinaldehyde from 11 Cis to All Trans-> Conformational change in opsin-> Hydrolysis of Rhodopsin (Visual purple) to release All Trans retinaldehyde and opsin
Q-257. A protein with molecular weight of 100 kD is subjected to SDS PAGE electrophoresis. The SDS PAGE electrophoreses pattern show two widely separated bands of 20 kD and 30kd after addition of mercapto-ethanol. The true statement regarding this will be
a) The protein has undergone complete lysis
b) The protein is a monomer of 20 kD and 30 kD protein
c) The protein is a dimer of two 20 kD and 30 kD protein
d) The protein is a tetramer of 20 kD and 30 kD proteins
Answer: The protein is a dimer of two 20 kD and 30 kD protein
Explanation:
The protein is a dimer of two 20 kD and 30 kD-> 2X 20 + 2X30 = 100 kD
Q-258. Rothera’s test used for detection of
a) Proteins
b) Glucose
c) Fatty Acid
d) Ketones
Answer: Ketones
Explanation:
Rothera’s test:
The three main ketone bodies are acetone, acetoacetic acid and beta-hydroxy-butyric acid.
Acetone and acetoacetic acid react with sodium nitropruside in the presence of alkali to produce a purple color.
If acetone and acetoacetic acid are present in urine, then a purple color will form at the junction of the two layers within 30-60 seconds.
Ketone Bodies – Rothera’s test
Bilirubin – (Harison spot test) Fouchet’s test
Urobilinogen – Erhlich’s test
Q-259. Inulin like fructans are used as prebiotics as they are non digestible. Resistance to digestion in the upper GI tract results
a) Absence of digestive enzyme in the upper GIT
b) Beta configuration of anomeric C2
c) Low pH of the stomach
d) Presence of alpha-osidic linkages
Answer: Beta configuration of anomeric C2
Explanation:
Prebiotics are non digestible food ingredients that beneficially affect the host by selectively stimulating the growth and activity of health promoting colonic bacteria.
Inulin-type fructans resist digestion and function as prebiotics improving bowel habits.
But, unlike most dietary fibers, their colonic fermentation is selective.
The beta configuration of anomeric C2 in fructose monomers is thought to make Inulin like fructans resistant to hydrolysis by the human digestive enzymes which are mostly specific for alpha-osidic linkage they also resist the acid hydrolysis in the stomach.
Q-260. Branched chain ketoacid decarboxylation is defective in
a) Maple syrup urine disease
b) Hartnup disease
c) Alkaptonuria
d) GMI Gangliosidosis
Answer: Maple syrup urine disease
Explanation:
Maple syrup urine disease-> Inherited deficiency of branched chain keto-acid dehydrogenase-> Defective oxidative decarboxylation of branched chain keto-acidosis
Hartnup disease-> Defective transport of mono-amino-mono-carboxylic amino acids in intestinal mucosa and renal tubules
Alkaptonuria-> Deficiency of Homogentisic acid oxidase-> Defective breakdown of Homogentisic acid