Module 2: Biochemistry - Practice Questions - PACOP Green

The inhibition in noncompetitive reaction _________________.

a. competes with the active site of the enzyme

b. binds simultaneously with substrate other than the active site

c. increases the rate of reaction

d. both b and c

B

The order and sequence of amino acid in a polypeptide determines what protein structure

a. primary

b. secondary

c.tertiary

d. quaternary

A

Amino acids that cannot be synthesized in the organism are called__________.

a. non essential amino acids

b. essential amino acids

c. standard amino acids

d. alpha amino acids

B

Which hormones regulates the level of blood sodium?

a. aldosterone

b. sterol

c. corticosteroid

d. cortisone

A

It is a precursor of vit. A

a. B-carotene

b. retinol

c. retinal

d. opium

A

Which of the following is a precursor of vitamin D?

a. prostaglandin

b. linoleic acid

c. cholesterol

d. aldosterone

D

Which of these class of enzymes introduces double-bond by the removal of hydrogen

a. dehydronegase

b. dehydrolase

c.decarboxylase

d. lipase

D

The ionic property of amino acid is exhibited by its

a. zwitterions form

b. NH2 group

c. COO group

d. positively charged groups

A

All of the following are simple proteins except:

a. glutelins

b. globulins

c. albumins

d. glycoproteins

D

The simplest monosaccharide is

a. erythrose

b. starch

c. glyceraldehydes

d. arabinose

C

Denaturation of protein is a result of

a. cleavage of the peptide bond

b. formation of H-bond

c. breaking of H-bond

d. none of these

C

Competitive inhibition is a _________________ reaction.

a. reversible

b. irreversible

c. pH ^ temperature dependent

d. none of these

A

In the Seliwanioff's test, the reaction of resorcinol and acid on the sugar forms___________.

a. hydroxymethyl furfural

b. pyranose

c. hydraxine

d. purine

A

In the Seliwanioff's test, the reaction of resorcinol and acid on the sugar forms___________.

a. hydroxymethyl furfural

b. pyranose

c. hydraxine

d. purine

A

It is the type of enzyme inhibition reaction whereby the inhibition competes with the substrate active site.

a. competitive inhibition

b. noncompetitive

c. reversible inhibition

d. incomplete inhibition

A

The following are waxes except:

a. beeswax

b. sperm oil

c. bile acids

d. lanolin

A

The inactive form of enzymes are called ___________.

a. zymogens

b. apoenzymes

c. cofactor

d. both B & C

A

Which of the following amino acids has no alpha amino group?

a. proline

b. hydroxyproline

c. glycine

d. both a and ?

D

An enzyme is a substance which

a. convert heat to energy

b. act as a catalyst

c. change chemically in reaction

d. is not specific in reaction

B

Milk curdling enzyme present in gastric juice of infants:

a. pepsin

b. rennin

c. trypsin

d. maltase

B

Carbohydrates are

a. polyhydroxyaldehydes / polyhydroxyketones

b. polyhydroxy acids

c. hemiacetals

d. polymers of amino acids

A

Insulin is usually classified as:

a. protein

b. enzyme

c. hormone

d. carbohydrates

C

What amount of glucose is present in the human blood?

a. 60 to 90 mg in 100 ml blood

b. 5 to 6 g in 100 ml blood

c. 2% of the total human body weight

d. none of these

A

It is the organelle which serves as the site of the electron transport chain.

a. mitochondria

b. ribosome

c. nucleus

d. lysosome

A

The end product of the hydrolysis of glycogen is:

a. galactose

b. fructose

c. glucose

d. arabinose

C

Iodine test is a reaction which may be used to identify carbohydrates. The reaction is due to

a. presence of the free aldehyde group

b presence of alcohol group

c. presence of amylose portion

d. presence of glucose

C

Benedict's reagent yield positive result to:

a. monosaccharide only

b. reducing sugars

c. sucrose

d. polysaccharides

B

Hypertonic solutions will cause the cell to:

a. swell

b. shrink

c. burst

d. undergo hemolysis

B

Rancidity of fats maybe due to:

a. oxidation

b. hydrogenation

c. saponification

d. condensation

A

The deficiency of this hormone causes diabetes mellitus:

a. progesterone

b. testosterone

c. insulin

d. glucagons

C

The active proteolytic enzyme in gastric juice is:

a. pepsin

b. trypsin

c. maltase

d. catalase

A

The site of oxidation reaction in electron transport chain is in the

a. nucleus

b. mitochondrion

c. ribosome

d. golgi bodies

B

Protein digestion starts in the

a. mouth

b. stomach

c. intestine

d. pancreas

B

The conversion of an amino acid to sugar is:

a. gluconeogenesis

b. glycolysis

c. glycogenesis

d. glycogenolysis

A

Which of the following is not an amino acid?

a. leucine

b. choline

c. valine

d. glycine

B

When trypsinogen is conoverted into tyrpsin, the enzyme is called:

a. pepsin

b. zymogen

c. enterokinase

d. amylase

C

The protein part of the enzyme molecule is the:

a.apoenzyme

b.coenzyme

c. cofactor

d. holoenzyme

A

Optimum temperature for enzyme activity in the body:

a.40oC

b.60oC

c. 37oC

d 10oC

C

Glucose is stored in the liver, as:

a. galactose

b. glycogen

c. lactose

d. fructose

B

The enzyme confirmation adapts to the incoming substrate in

a. Lock and Key theory

b. glycogenesis

c. competitive inhibition

d. glycogenolysis

B

The process of converting glucose into glycogen is called

a. gluconeogenesis

b. glycogenesis

c. glycolysis

d. glycogenolysis

B

All are pyrimidine bases except:

a. guanine

b.cystocine

c. uracil

d. thymine

A

Glucose, amino acid and fatty acid enter the citric acid cycle by their conversion into:

a. pyruvate

b. acetyl CoA

c. acetoacetyl CoA

d. palmitic acid

B

A hormone which stimulates glycogenesis:

a. insulin

b. glucagons

c. epinephrine

d. vasopressin

A

These are chemicals that are extracted from organism such as bacteria and can inhibit growth or destroy other

microorganisms:

a. antibiotic

b. enzyme

c. hormone

d. vitamins

A

The gland or tissue that regulates the blood glucose level.

a. parathyroid

b. thyroid

c. pancreas

d. adrenal

C

Which vitamin is formed in the body by exposure to ultraviolet Irradiation or sunlight

a. vit. A

b. vit. B

c. vit. C

d. vit. D

D

Excess vit. A & D is stored in the body, but excess vit. C & D is readily excreted. What property shows this?

a. vit C & D are water soluble

b. vit. A & D are fat soluble

c. both a & b

d. none of these

C

A

The vitamin which is used in the prevention of degenerative changes in the central nervous system.

a. vit. A

b. vit. B complex

c. vit. C

d. vit. D

B

It is a model which best explains the enzyme-substrate action

a. lock & key

b. molecular

c. VSEPR

d. Kreb

A

The activation of pepsinogen requires:

a. pepsin

b. NaOH

c. enterokinase

d. HCL

D

DNA is primarily found in the

a. cytosol

b. nucleus/mitochondria

c. cell wall

d. endoplasmic reticulum

B

It is the enzyme which hydrolyzed starch to dextrin and maltose

a. catalase

b. amylase

c. pepsin

d. lactase

B

A synthetic DNA is called

a. replicated DNA

b. plasmid

c. gene

d. recombinant DNA

D

Hydrolysis of ATP is an

a. energy requiring reaction

b. energy producing reaction

c. no energy is involved

d. energy is absorbed

B

Which of the following characteristic of lipid?

a. zwitterions

b. amphiphilic

c. hydrophobic

d. hydrophilic

C

It is a condition that results when sugar level is below normal

a. hypoglycemia

b. hyperglycemia

c. ketonuria

d. uremia

A

An example of globular protein

a. albumin

b. collagen

c. fibrin

d. silk

A

Complimentary base pairs in the DNA double helix are bonded by

a. H-bond

b. ester bond

c. vander waals

d. dipole dipole

A

Which nitrogen base is not found in DNA?

a. thymine

b. cytosine

c. uracil

d. guanine

C

An organic cofactor in an enzyme

a. vitamins

b. coenzymes

c. a & b

d. none of these

C

At what stage of glucose oxidation is most of the energy produced?

a. glycolysis

b. aerobic stage

c. glycogenesiS

d. glycogenolysis

B

The best known building blocks of RNA and DNA are

a. purines

b. pyrimidines

c. fatty acids

d. a and b

D

It is responsible for the storage and transmission of genetic information.

a. adenine

b. RNA

c. DNA

d. nucleic acid

C

Build up of urea in the kidney is called

a. ketonuria

b. glycemia

c. uremia

d. all of these

C

The transfer of genetic information from DNA by the formation of mRNA

a. transcription

b. translation

c.transamination

d. replication

A

What is the end product of electron transport chain?

a. oxygen

b. hydrogen

c. carbon dioxide

d. water

D

The energy producing reaction

a. metabolic

b. catabolic

c. anabolic

d. all of these

B

It is the molecule that directs the activity of the cells

a. DNA

b. RNA

c. nucleoproteins

d. hormones

D

The sugar involved in DNA

a. ribose

b. pentose

c. deoxyribose

d. xylose

C

The common metabolic pathway

a. glycosis

b. beta oxidation

c. Kreb's cycle

d. glucogenesis

C

Rosenheim's test is used to detect the presence of:

a. ethanolamine

b. choline

c. cholesterol

d. glycone moiety

B

Detects the presence of alpha amino acids:

a. Biuret

b. Molisch

c. Ninhydrin

d. Hopkins-cole

C

The process of producing fats from acetyl co-A is called

a. glycolysis

b. lipogenesis

c. glycogenolysis

d. glucogenesis

B

The ff. test reagents to detect the presence of amino acids, execpt:

a. Grignard's

b. Xanthoproteic

c. Millon-Nasse

d. Sakaguchi

A

The condition that lowers the pH of the blood due to starvation is called

a. acidosis

b. alkalosis

c. hyperglycemia

d. glycosuria

A

The substance responsible or the emulsion of fats is

a. HCI

b. bile acids

c. pepsin

d. trypsin

B

Hubl's solution is used to acertain degree of:

a. saturation

b. unsaturation

c. peroxidation

d. acidity

B

IUPAC name of acrolyn

a. pentenal

b. propenal

c. hexanal

d. acetone

B

The positive indication for the presence of glycerol in acrolein test:

a. yellow colored solution

b. black markings on filter

c. silver mirror formed in the test tube

d. play of colors, from blue to shades paper of red

B

Cerebrosides are positive in the ff. tests, except:

a. Molisch

b. Biuret

c. Lassaigne's

d. none of the above

B

Osmic test is used to detect the presence of _______ in lipids:

a. metals

b. prostate groups

c. unsaturated groups

d. glycerol

B

The most sensitive chemical test to detect the presence of glycerol in acrolein test:

a. Liebberman-Burchard

b. Salkowski reaction

b. Formaldehyde-sulfuric acid

d. Colorimetric spectrophotometry

A

The ff. are phospholipids, except:

a. plasmalogen

b. lecithin

c. cephalin

d. choline

D

A mixed triglyceride contains:

a. three similar fatty acids esterified with glycerol

b. two similar fatty acids esterified with glycerol

c. three different fatty acids esterified with glycerol

d. all of the above

C

The central compound found in the structure of sphingolipids:

a. glycerol

b. sphingosine

c. ceramide

d. phosphocholine

C

Lipid whose specific test is the Furter-Meyer test:

a. tocopherol

b. retinol

c. sphingomyelin

d. cerebroside

A

Precipitate of ___________ indicates the presence of phospholipids in the lipid sample:

a. ammonium phosphomolybdate

b. phosphorous periodate

c. phosphorous triiodide

d. phospho-ammonium sulfate complex

A

The ff. are glycolipids except:

a. globosides

b. phosphatides

c. gangliosides

d. cerebrosides

B

The parent compound of phosphoslipids:

a. glycerol

b. phosphatidic acid

c. ethanolamine

d. none of the above

B

A non-pentose sugar which is also positive for Tollen' sphloroglucinol test:

a. galactose

b. glucose

c. fructose

d. cellobiose

D

The reagent present is Molisch test which is responsible for the dehydration reaction:

a. sodium carbonate

b. magnesium stearate

c. sulfuric acid

d. NaOH

C

ID test to detect the presence of glycogen:

a. phloroglucinol

b. molisch

c. iodine

d. seliwanoff

C

The only sugar that readily forms insoluble osazone crystals:

a. lactose

b.sucrose

c. mannose

d. sucrose

C

Important structural material found in the exoskeletons of many lower animals:

a. chnondroitin

b. heparin

c. hyaluronic acid

d. chitin

D

Hydrolysis of osazones produce:

a. phenylhydrazones

b. ozones

c. sugars

d. none of the above

B

General term for a group of polysaccharides present in the primary cell wall:

a. xanthan

b. mucilage

c. pectin

d. carageenan

C

Specific test for galactose, due to the formation of highly insoluble crystals:

a. phenylhydrazine test

b. fermentation

c. mucic acid

d. molisch

C

Type of RNA which serves as template for the amino acid sequence being synthesized:

a. mRNA

b. tRNA

c. rRNA

d. none of the above

A