Biochem

Question 1

What is the most abundant organic molecules in living cells?
A. Proteins
B. Carbohydrates
C. Lipids
D. Fats

Answer 1

A

Question 2

Which of the following is NOT a steroid?
A. Sex hormones
B. Cholesterol
C. Adrenocortical hormones
D. Prostaglandin

Answer 2

D

Question 3

Bioprocess engineering deals with the

A. application of engineering principles to processes using living cells or their subcomponents
B. application of chemical, mechanical, biological, and industrial engineering
C. equipment design and manufacturing practices
D. All of the above

Answer 3

D

Question 4

Bacteria which convert alcoholic solution to vinegar are
A. coli
B. acetobacters
C. bacilli
D. proteins

Answer 4

B

Question 5

Amino acids required in the human diet and not synthesized by the body are called

A. specialized
B. essential
C. trace
D. accessory

Answer 5

B

Question 6

The nature of the peptide bond can best be explained as

A. A partial double bond
B. Aß-pleated sheet
C. An a-helix
D. A full double bond

Answer 6

A

Question 7

Hemoglobin has a quaternary structure and is made up of:

A. 6 polypeptide chains: 2 a-chains and 4ß-chains
B. 2 polypeptide chains: 1 a-chain and 1 B-chain
C. 4 polypeptide chains: 2 a-chains and 2ß-chains
D. 5 polypeptide chains: 2 a-chains and 3 B-chains

Answer 7

C

Question 8

Which of the following is least affected in protein denaturation?

A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Quaternary structure

Answer 8

A

Question 9

A nucleotide consists of:

A. A sugar, a base, and a phosphate
B. A sugar and a phosphate
C. Paired bases
D. A sugar, a base, and 3 phosphates

Answer 9

A

Question 10

The sugar in RNA is ______, , and in DNA is _____

A. Glucose, fructose
B. Galactose, mannose
C. Ribose, deoxyribose
D. Xylose, fructose

Answer 10

C

Question 11

Whose x-ray work aided Watson and Crick in their discovery of the double helix?
A. W. H. Bragg
B. L. Pauling
C. R. Franklin
D. Lederberg

Answer 11

C

Question 12

In a DNA double helix, the two DNA chains are held together primarily by:

A. Covalent bonds between the base pairs
B. lonic bonds between the base pairs
C. Coordinate bonds between the base pairs
D. Hydrogen bonds between the base pairs

Answer 12

D

Question 13

What does ligase do during DNA replication?

A. It synthesizes the lagging strand
B. It makes copies of mRNA from DNA
C. It joins nicks in DNA strands
D. It digests mRNA when it is no longer needed

Answer 13

C

Question 14

Which base is only present in mRNA?
A. Thymine
B. Uracil
C. Adenine
D. Cytosine

Answer 14

B

Question 15

Question 16
RNA is synthesized on a DNA template in a process called ______, which utilizes the enzyme _______.

A. Translation, RNA polymerase
B. Transcription, DNA polymerase
C. Transcription, RNA polymerase
D. Replication, DNA polymerase

Answer 15

C

Question 16

Which of the following RNAs bind to an amino acid?
A. mRNA
B. tRNA
C. snRNA
D. rRNA

Answer 16

B

Question 17

The ultimate source of energy that sustains living systems is:

A. Glucose
B. Sunlight
C. Oxygen
D. Carbon Dioxide

Answer 17

B

Question 18

Question 19
What would be the molecular formula for a polymer made by linking 10 glucose molecules together by condensation?
А. С6о Н100 O50
В. С6о Н102 O51
С. Сбо H120 O60
D. (C6H12 O6) 10

Answer 18

B

Question 19

What does insulin do?

A. Inhibit gluconeogenesis and stimulate glycolysis
B. Stimulate both gluconeogenesis and glycolysis
C. Stimulate gluconeogenesis and inhibit glycolysis
D. Inhibit both gluconeogenesis and glycolysis

Answer 19

A

Question 20

An important role of cholesterol is to:

A. Modulate membrane fluidity
B. Enhance blood circulation
C. Prevent bile salts formation
D. None of these

Answer 20

A

Question 21

Ascorbic acid acts as a/an:
A. Oxidizing agent
B. Reducing agent
C. Chelating agent
D. Crosslinking agent

Answer 21

B

Question 22

A fat-soluble vitamin that regulates blood clotting is
A. Vitamin A
B. Vitamin D
C. Vitamin C
D. Vitamin K

Answer 22

D

Question 23

Which of the following bacteria eats plastic

A. Ideonella paraiensis
B. Ideonella homoiensis
C. Ideonella sakaiensis
D. Ideonella polyiensis

Answer 23

C

Question 24

The simplest way to differentiate a prokaryotic cell from a eukaryotic cell is:

A. To look for a plasma membrane
B. To see if a nucleus is present
C. To check for the presence of DNA
D. To determine whether the cell is an entire organism or not

Answer 24

B

Question 25

Which of the following microorganisms is used for the production of citric acid? A. Lactobacillus Bulgaricus B. Aspergillus Niger C. Saccharomyces Cereviside D. Streptococcus Lactis

Answer 25

B

Question 26

Balanced growth is defined as: A. Cells in culture maintaining a constant chemical composition B. Balancing the growth while controlling the ph C. Balancing the growth while controlling the temperature D. Balancing the growth while controlling the nutrient composition

Answer 26

A

Question 27

The binomial name for a microbe is composed of A. Its kingdom and genus names B. Its genus name and a species modifier C. Its family and class names D. Its genus and species names

Answer 27

D

Question 28

All of the following are considered eukaryotes except A. Archaea B. Protozoa C. Fungi D. Humans

Answer 28

A

Question 29

The common word for bacteria which are spherical in shape is: A. Coccus B. Spirillum C. Bacillus D. Pleomorphic

Answer 29

A

Question 30

Starvation proteins or metabolites are produced by a culture during which of the following phases of the growth cycle? A. Lag phase B. Stationary phase C. Exponential phase D. Death phase

Answer 30

B

Question 31

The period between inoculation of bacteria in the culture medium and the beginning of multiplication is known as: A. Stationary phase B. Lag phase C. Exponential phase D. Decline phase

Answer 31

B

Question 32

An organism that grows best at 50°C is called: A. Psychrophilic B. Thermophilic C. Mesophilic D. None of these

Answer 32

B

Question 33

Food preservation by using salts and sugars works by A. Raising pH B. Lowering osmotic pressure C. Creating a hypertonic environment D. Creating a hypotonic environment

Answer 33

C

Question 34

The concept of using microbes to help clean up the environment is called: A. Pasteurization B. Bioremediation C. Fermentation D. Sterilization

Answer 34

B

Question 35

Mucus helps in protecting against pathogens by: A. Lowering the pH B. Facilitating the growth of normal flora C. Restricting access to mucosal surfaces D. Sequestering iron

Answer 35

C

Question 36

The Monod model predicts that the specific growth rate: A. Will increase with the concentration of the growth-limiting substrate until it reaches a maximum value B. Will decrease with the concentration of the growth-limiting substrate C. Will increase with the concentration of the growth-limiting substrate D. Does not depend on the growth-limiting substrate

Answer 36

A

Question 37

Enzymes are basically: A. Proteins B. Fats C. Vitamins D. Carbohydrates

Answer 37

A

Question 38

Which of the following statements is true for enzymatically catalyzed reactions? A.The activation energy of the reaction is lowered so that a larger proportion of the substrate qualifies to overcome it B. Additional substrate molecules are energized to overcome the activation energy of the reaction C. The activation energy of the reaction is increased, thus decreasing the likelihood that any substrate molecules will overcome it D. The activation energy of the reaction is lowered so that few substrate molecules can overcome it

Answer 38

A

Question 39

When the substrate concentration is equal to 0.1Km' the velocity of an enzyme-catalyzed reaction is: A. 0.1V B. 0.5V C. 0.3V D. 0.7V

Answer 39

A

Question 40

Question 43 Lactase, also known as B-galactosidase, catalyzes the hydrolysis of lactose to produce glucose and galactose from milk and whey. Experiments are carried out to determine the kinetic parameters for the enzyme. Processing of the initial rate data using a Lineweaver-Burk plot gave the best-fit linear equation: y=4.43x10-4+0.01738x. Substrate concentrations were in M, and reactions velocities in M/min. Evaluate the enzyme's V MAX• A. 2257M/min B. 5754M/min C. 4430M/min D. 0.0174M/min

Answer 40

A

Question 41

Question 45 In a batch-fed reactor configuration, substrate is added: A. Only at the beginning of the fermentation process B. Periodically throughout the fermentation process C. Only at the end of the fermentation process D. Never

Answer 41

B