Biochem Chapter 1

Thought Question: Humans synthesisze most of the cholesterol requires for cell membranes and for the synthesis of vitamin D and steroid hormones. What would you expect to happen if a person's diet is high in cholesterol?

00

Choose the amino acid that can function as a neurotransmitter Glutamic acid Alanine Tyrosine Lysine Cysteine

A

Which of the following amino acids contain a hydrophobic side chain Leucine Arginine Glutamine Glutamic acid Aspartic acid

A

Which of the following is not a component of DNA Uracil Adenine Cytosine Guanidine Thymine

A

An organisms entire set of DNA is called A. Genome B. Genetic sequence C. Polynucleotide sequence D. Gene E. Inheritance

A. Genome

The conversion of earths atmosphere from anerobic to aerobic was due to the development of _________________ by cyanobacteria Photosynthesis Metabolism Chemosynthesis Oxidation of iron Fixation of nitrogen as cyanide

A. Photosynthesis

The following is an example of which reaction class? CH3Br + HSCH2CH(NH2)COOH CH3SCH2CH(NH2)COOH + Br- + H+ A) Substitution B) Elimination C) Addition D) Isomerization E) Oxidation/Reduction

A. Substitution

) The ultimate source of energy for life on earth is __________. A) The sun B) Geothermal heat C) Carbohydrates D) Fats E) Other organisms

A. The Sun

The assumption that a complete understanding of a living organism can be obtained solely by investigating all of its components is called _________. A) Systems biology B) Reductionism C) Emergence D) Robustness E) Feedback control

B

The majority of Earth's species belong to which of the following classifications Eukaryotes Prokaryotes Viruses Mammals Archea

B

The sum total of all reactions of a organism is called Life Metabolism Biosynthesis Anabolism Energetics

B

Which of the following is not a component of nucleic acid? A) Nucleotides B) Glucose C) Phosphate group D) Purines E) Pyrimidines

B

The following molecule is an example of which class of compounds? CH3CH2CH2COOH A) Hydrocarbon B) Acid C) Alcohol D) Aldehyde E) Ketone

B Acid

The major function of carbohydrates is A. Catalysts and structural elements B. Energy sources and structural elements C. Genetic information D. Protein synthesis E. Insulation

B. Energy sources and structural elements

The largest mass extinction also known as the great dying was called the A. Cenezoic extinction B. Permian extinction C. Mesozoic event D. Great ice age E. The great plague

B. Permian extinction

Biochemistry is defined as A) The study of life processes B) The study of the molecular basis of life C) The study of living organisms D) The study of organic compounds in living organisms E) The study of living compounds

B. The study of molecular basis of life

Consider the following molecule. Which arrow is pointing to a peptide bond?

C

One of the principal methods that organisms use to obtain energy from chemical bonds is by ___________. A) Substitution reactions B) Dehydration reactions C) Oxidation/reduction reactions D) Hydration reactions E) Addition reactions

C

The following is an example of which reaction class HOOCCH=CHCOOH + H2O HOOCCH2CH(OH)COOH A) Substitution B) Elimination C) Addition D) Isomerization E) Oxidation/Reduction

C

The largest molecules in living organisms are _________. A) proteins B) lipids C) nucleic acids D) carbohydrates E) steroids

C

Which of the following classes of biomolecules are the most abundant in nature? A) Lipids B) Amino acids C) Carbohydrates D) Proteins E) Nucleotides

C

Which of the following small molecules do not for biopolymers Amino acids Sugars Fatty acids Nucleotides C and D

C

The functional group present in the following molecule is called: A) Amine B) Ketone C) Amide D) Ester E) Acid

C. Amide

The most abundant biomolecules found in nature are A. Amino acids B. Fatty acids C. Carbohydrates D. Proteins E. Fats

C. Carbohydrates

A constant source of _______ is required for maintenance of a cell's ordered state. A) Heat B) Oxygen C) Energy D) Stimulus E) Water

C. Energy

The following molecule is an example of which class of compounds? CH3CH2CH2COOCH2CH3 A) Hydrocarbon B) Acid C) Ester D) Ether E) Aldehyde

C. Ester

The chemical properties of organic molecules are determined by specific arrangements of atoms called _____________. A) Structure B) Bonds C) Functional groups D) Radicals E) Molecules

C. Functional Groups

Which of the following is not considered a class of small biomolecule? A) Amino acid B) Sugar C) Nucleic Acid D) Fatty acid E) Nucleotide

C. Nucleic Acid

The most prominent function of RNA is A. Energy source B. Nutrient source C. Protein synthesis D. Structural elements E. B and C

C. Protein synthesis

Most biomolecules can be considered to be derivatives of Amino acids Carbohydrates Fats Hydrocarbons Alcohols

D

Which of the following is not true of life? A) Life is cellular B) Life is information based C) Life is complex and dynamic D) All living things produce energy using mitochondria E) Life adapts and evolves

D

The following molecule is an example of which single class of compounds? CH3CH2CH(NH2)COOH A. Amine B. Acid C. Ester D. Amino Acid E. Alcohol

D. Amino Acid

Which of the following is the basic structural unit of living organisms? A) Nucleus B) Cell membrane C) Tissue D) Cell E) Cytoskeleton

D. Cell

The field of study associated with the investigation of gene expression patterns is called: A) Proteomics B) Bioinformatics C) Genomics D) Functional genomics E) Synomics

D. Functional Genomics

Which of the following is not characteristic of an autopoietic system? A) Autonomous B) Self-organizing C) Self-maintaining D) Intelligent E) B and D

D. Intelligent

All of the following classes of compounds are lipids except _______. A) fats B) sterols C) fatty acids D) phosphoglycerides E) nucleotides

E

The following is an example of which reaction class? CH3CH2OH CH3CHO + H2O A) Substitution B) Elimination C) Addition D) Isomerization E) Oxidation/Reduction

E

Which of the following classes of compounds make up most of the mass of an organism? A) Amino acids B) Proteins C) Lipids D) Carbohydrates E) Water

E

Which of the following is not a basic element of life Phosporus Hydrogen Nitrogen Oxygen All of the above are basic elements of life

E

Which of the following is not an example of a macromolecule? A) Nucleic acid B) Protein C) Polysaccharide D) Enzyme E) Amino acid

E. Amino Acid

Which of the following is not a common component of biomolecules? A) Carbon B) Hydrogen C) Oxygen D) Nitrogen E) Chlorine

E. Chlorine

Which of the following is not a waste product of living organisms A) Carbon dioxide B) Water C) Urea D) Ammonia E) Glycine

E. Glycine

Which of the following is not a core principle of systems biology? A) Emergence B) Robustness C) Redundancy D) Modularity E) Limit of resolution

E. Limit of resolution

Thought Question: The bases of two complementary DNA chains pair with each other because of hydrogen bonding, that is, Thymine-Adenine base pair. A new nucleotide has been isolated containing the following purine. Which of the normal purines and pyrimidines (A,G,C, or T) would you expect to pair with it?

Guanine

Tay-Sachs disease is devastating genetic neurological disorder caused by the lack of the enzyme that degrades a specific lipid molecule. When the molecule accumulates in brain cells an otherwise healthy child undergoes motor and mental deterioration within months after birth and dies by the age of 3 years. In general terms, how would a system biologist evaluate this phenomenon?

In the normally function system the lipid molecule is not toxic. In individuals that lack the key enzyme, this lipid begins to accumulate within neurons and with other brain cells. Its physical presence interferes with the way nerve tracts are laid down. Neurological systems that require integration of brain functions begin to fail.

Thought Question: Why are fatty acids the principal long-term energy reserve of the body?

They hold more energy value and are insoluble so they store easier.

Genetic information for living things is stored in: a. DNA, also known as deoxyribonucleic acid b. Polysaccharides such as glycogen or amylopectin c. Triacylglycerols such as glyceryl tristearate d. Organelles such as lysozomes e. Tiny granules of ribonucleic acid

a. DNA, also known as deoxyribonucleic acid.

During catabolism: a. Large, complex molecules are converted into many smaller, simple molecules b. ny large, complex molecules are converted into larger, simple molecules c. Many small, simple molecules are converted into a few large, complex molecules d. A few small, simple molecules are converted into many large, complex molecules e. The size and complexity of molecules involved remains about the same

a. Large, complex molecules are converted into many smaller, simple molecules.

The most important function of DNA in prokaryotes and eukaryotes is: a. To serve as a repository for genetic information b. To provide the directions for protein synthesis c. To act as a factory for protein synthesis d. To maintain osmotic pressure e. To function as the main mechanism for energy transformation within cells

a. To serve as a repository for genetic information .

Passage of information from DNA to RNA is known as: a. Transcription b. Translation c. Replication d. Homeostasis e. The central dogma

a. Transcription.

Viruses differ from prokaryotes and eukaryotes in this respect: a. Viruses have no cells b. Viruses can not reproduce c. Viruses do not employ nucleic acids to reproduce d. Prokaryotes and eukaryotes need host cells to reproduce e. Virus particles require more energy than prokaryotes and eukaryotes

a. Viruses have no cells.

Hydrophilic substances are usually soluble in: a. Water or aqueous solutions such as the cell cytoplasm b. Gasoline, ether, or other nonpolar solvents c. Nonpolar solvents such as gasoline and ether d. Any solvents made up of molecules containing hydrogen e. Nonaqueous portions of cell membranes

a. Water or aqueous solutions such as the cell cytoplasm.

Proteins are made up of long chains of: a. Glucose molecules attached end to end b. Amino acids attached by peptide (amide) bonds c. Complex lipids such as stearic acid or cholesterol d. Deoxyribonucleic acids, which store genetic information e. Organic subunits such as ethene or propene

b. Amino acids attached by peptide (amide) bonds.

For cells to remain highly ordered, they need a constant supply of: a. Sugar b. Energy c. Water d. Salt e. MTV

b. Energy.

Eukaryotic cells differ from prokaryotic cells in one major respect: a. Eukaryotic cells are smaller than prokaryotic cells b. Eukaryotic cells are larger than prokaryotic cells c. Eukaryotic cells are more colorful than prokaryotic cells d. Eukaryotic cells are faster than prokaryotic cells e. Eukaryotic cells are firmer than prokaryotic cells

b. Eukaryotic cells are larger than prokaryotic cells.

Although most mutations are silent, some may actually help the organism by: a. Ridding the cell of excess RNA b. Helping the organism adapt to new circumstances c. Limiting the reproductive success of the offspring d. Causing errors in copying DNA e. Limiting overpopulation

b. Helping the organism adapt to new circumstances.

Examples of macromolecules include: a. Sugars b. Proteins c. Amino acids d. Hydrochloric acid e. Salts

b. Proteins.

Unlike prokaryotic life forms, eukaryotes: a. Are relatively few in number and contain no organelles b. Contain nuclear material bound by a membrane c. Are relatively large and contain organelles d. Are made up of bare nuclear material e. Lack nuclei and cellular organelles

c. Are relatively large and contain organelles.

The function of transfer RNA is to: a. Transfer RNA from one part of the cell to another b. Carry information from the genetic code on DNA to ribosomes to direct protein synthesis c. Carry amino acids to the ribosome for protein synthesis d. Recognize the anticodon that prevents coding e. Temporarily store the genetic code during transcription

c. Carry amino acids to the ribosome for protein synthesis.

Human beings are best categorized as: a. Autotrophs, which transform the energy of the sun b. Chemoheterotrophs, which use preformed food molecules as their only source of energy c. Heterotrophs, which can either produce their own energy or use organic substances obtained from other organisms to obtain energy d. Extremophiles, which exist under extremes of climate, temperature, and light e. Photoheterotrophs, which use both light and organic biomolecules as energy sources

c. Heterotrophs, which can either produce their own energy or use organic substances obtained from other organisms to obtain energy.

Energy can best be defined as: a. The rate of doing work b. Hotness or coldness c. The ability to do work d. A way of storing work e. Kilojoules/kilogram

c. The ability to do work.

Messenger RNA is a specialized molecule whose most important function is to: a. Stabilize ribosomes during translation b. Store genetic information so that our offspring resemble us c. Allow rapid mutations of bacteria under extreme conditions d. Carry information from DNA to ribosomes to direct protein synthesis e. Carry amino acids to ribosomes so they may be used to form proteins

d. Carry information from DNA to ribosomes to direct protein synthesis.

Organisms that can live and function at very high temperatures include some archae called: a. Escherichia coli b. Hydrophobes c. Prions d. Extremophiles e. Antibiotics

d. Extremophiles.

The word B homeostasisB best describes: a. Any reaction at equilibrium b. A condition in which a number of members of a group remain homogeneous c. The general condition in which all cellular activity is at a standstill d. The general condition of maintenance of health and cellular activities that continue life e. A philosophy that is dedicated to protection of oneB s homeland

d. The general condition of maintenance of health and cellular activities that continue life.

Cell division and the movement of organelles within cells depend on a framework of protein filaments called: a. Lipid bilayers b. Starch granules c. Molecular chaperones d. Amino acids e. Cytoskeletons

e. Cytoskeletons

Biochemical catalysts are called: a. Deoxyribonucleic acid b. Manganese dioxide c. Hydrogen peroxide d. Polysaccharides e. Enzymes

e. Enzymes.

The B central dogmaB states that information always passes from DNA to RNA except: a. In most eukaryotic cells b. In all cells of the archae c. In all prokaryotic cells d. In all viruses e. In retroviruses such as HIV

e. In retroviruses such as HIV.

Oxidation reactions in biochemistry can be recognized by: a. Loss of oxygen during the reaction b. Transfer of oxygen from one carbon to a new part of the same structure c. An addition of hydrogen to or loss of oxygen from a molecule d. Addition of electrons to a positive ion such as Fe +3 e. Loss of hydrogen from or addition of oxygen to a molecule

e. Loss of hydrogen from or addition of oxygen to a molecule.

When compared to fatty acids, nucleic acids, and carbohydrates, proteins are found to contain more: a. Carbon b. Hydrogen c. Oxygen d. Phosphorus e. Nitrogen

e. Nitrogen.