Cell Biology Exam 1 Chapters 1, 2, 3, 4, 7, 8, 16, 17, 18, 19 ,20

Which monomers make up RNA?

nucleotides

Which of the following is not attached to the central carbon atom in an amino acid?

an Oxygen

The _____ is composed of DNA and protein.

chromatin

Heterochromatin is highly ________, thus constitutive heterochromatin plays a(n) ________ role and facultative heterochromatin functions in ________.

compacted; structural; regulation of gene expression

Which polymers are composed of amino acids?

proteins

Cholesterol is a ________, which ________.

steroid; is a component of eukaryotic membranes and is the basis for many animal and plant hormones

You can tell that this is an image of a DNA nucleotide and not an RNA nucleotide because you see a _____

sugar with two, and not three, oxygen atoms

Why isn't this insect drowning?

surface tension

DNA is composed of building blocks called _____.

nucleotides

This is an image of a(n) _____.

nucleotide

Which of these organelles produces H2O2 (Peroxide) as a by-product?

Peroxisome

Proteins are polymers of _____.

Amino Acids

The DNA-containing region of this bacterial cell is indicated by the letter _____.

D

The letter C indicates _____.

Histones

Many cell biologists claim that monosaccharides are older (chronologically and evolutionarily) than nucleotides. Which of the following observations supports this hypothesis?

-All nucleotides contain monosaccharides. -Monosaccharides are metabolized by cells to make nucleotides (i.e., glucose is metabolized by the enzymes of glycolysis to make ATP). -Nucleotides have more chemically complicated structures than monosaccharides. -(CORRECT) All of the other answer choices support this hypothesis.

Which molecules do not normally cross the nuclear membrane?

DNA

_____ is/are identical in structure to centrioles.

Basal Bodies

Which part of an amino acid is always acidic?

Carboxyl functional group

The letter A indicates a _____. O O P O -----Ch2 O I ^^A^^ C--(etc.)

phosphate group

Which statements are true for chloroplasts? Select the three that apply. -They are the sites of reactions that convert chemical energy to ATP. -They contain the green pigment chlorophyll. -They are the sites of reactions that convert solar energy into chemical energy. -Their matrix contains enzymes that function in cellular respiration. -They have membranous sacs called thylakoids that are surrounded by a fluid called stroma. -Their inner membrane has infoldings called cristae.

-They contain the green pigment chlorophyll. -They are the sites of reactions that convert solar energy into chemical energy. -They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.

In a nucleotide, the nitrogenous base is attached to the sugar's _____ carbon and the phosphate group is attached to the sugar's _____ carbon.

1'........5'

When examining a five-carbon sugar to determine if it is ribose or deoxyribose, one looks to see if there are two H on the _____ carbon in the structure.

2'

If a strand of DNA has the nitrogen base sequence 5'-ATTTGC-3', what will be the sequence of the matching strand?

3'-TAAACG-5'

For a double-stranded DNA molecule in which 40% of the bases are either G or C, what can you conclude about its content of the base A?

30% of the bases must be A.

Nucleic acids are assembled in the _____ direction.

5' to 3'

What is the complementary DNA sequence for the DNA strand shown in the figure below? 3'-ATTGCAGTACC-5'

5'- TAACGTCATGG -3'

One strand of a region of DNA has the sequence 5'-ATTCCG-3'. The complementary strand for this one is __________.

5'-CGGAAT-3'

What is the complementary DNA sequence to 5′ ATGCTTGACTG 3′?

5′ CAGTCAAGCAT 3′

If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?

75

Which of the following statements about the formation of polypeptides from amino acids is true? -Polypeptides form by condensation or hydrolysis reactions. -A bond can form between any carbon and nitrogen atom in the two amino acids being joined. -The reaction occurs through the addition of a water molecule to the amino acids. -A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.

A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.

Where would RNA polymerase attach?

A

Which of these structures stores, modifies, and packages products?

A

Based on the principle of complementary base pairing, you would expect the percentage of __________ to be equal to the percentage of __________.

A:T

Which of the following would NOT be a rational explanation for why the three-dimensional structure of a protein is driven and stabilized largely by noncovalent bonds rather than covalent bonds? -Forming a significant number of covalent bonds would require substantial energy input for protein folding. Noncovalent bonds allow proteins to self-assemble and largely fold spontaneously. -Protein function (transport, enzyme catalysis, etc.) may require flexibility in the three-dimensional structure to allow for conformational change, and if protein three-dimensional structures were held together by mostly covalent bonding, this might be too difficult to accomplish. -Proteins will need to be unfolded to cross biological membranes, and if their three-dimensional structures were held together by mostly covalent bonding, this might be too difficult to accomplish. -All of the listed answer choices are rational explanations for why the three-dimensional structure of a protein is driven and stabilized largely by noncovalent bonds rather than mostly covalent bonds.

All of the listed answer choices are rational explanations for why the three-dimensional structure of a protein is driven and stabilized largely by noncovalent bonds rather than mostly covalent bonds.

Which of the following is NOT a consequence of the polar nature of water? -Water has a high heat of vaporization. -Water has a high surface tension. -Water has a high specific heat. -All of the other answer choices are consequences of the polar nature of water.

All of the other answer choices are consequences of the polar nature of water.

Which of the following is NOT a reason for the following statement to be INCORRECT concerning the alpha-helix and beta-sheet secondary structures? "Alpha helices and beta sheets are stabilized by intermolecular ionic interactions between amino acid R groups, which have no influence on the type of secondary structure formed. -Alpha helices have only intramolecular interactions, whereas beta sheets can have intramolecular and intermolecular interactions. -Alpha helices and beta sheets are characterized by interactions between the NH and CO groups, not the R groups, along the polypeptide backbone. -Alpha helices and beta sheets are stabilized by hydrogen bonds, not ionic bonds. -All of the other answer choices are reasons that the statement is incorrect.

All of the other answer choices are reasons that the statement is incorrect.

Trans fats are... -are present in small amounts in meat and dairy products. -are unsaturated fatty acids. -are associated with an increased risk of heart disease. resemble saturated fatty acids in shape. -All of these statements are true.

All of these statements are true.

Which of the following factors does NOT contribute to our inability to predict protein tertiary structure using only our knowledge of protein primary structure? -The large number of monomers available, as well as the relatively large size of proteins constructed with these monomers, means that almost every protein tertiary structure will be complicated. -We cannot reliably predict which stretches of a protein primary structure will definitively form a particular element of secondary structure. -There is no predictable trend as to which intermolecular forces (ionic interactions, hydrogen bonds, etc.) are more or less important in determining a protein tertiary structure. -All the other answer choices contribute to our inability to predict protein tertiary structure using only our knowledge of protein primary structure.

All the other answer choices contribute to our inability to predict protein tertiary structure using only our knowledge of protein primary structure.

Which of the following is not a polymer of numerous monomer units? -an RNA molecule -a polypeptide -a phospholipid -starch -cellulose

Phospholipid

Which of the following accurately details the relationship between wavelength of illumination, lens quality, magnification, and the limit of resolution for light microscopy? -As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will decrease. -As shorter wavelength illumination and better quality lenses are used, magnification will decrease and the limit of resolution will decrease. -Magnification and limit of resolution are independent of wavelength of illumination and lens quality for light microscopy. -As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will increase.

As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will decrease.

In the accompanying image, a nucleotide is indicated by the letter _____.

B

You analyze a DNA sample and find that its base composition is 30% A, 20% T, 30% G, and 20% C. What can you conclude about the structure of this DNA?

Because A does not equal T, and G does not equal C, this cannot be a double-stranded DNA molecule. It must therefore be a single-stranded DNA.

Which of the following is true concerning both mitochondria and chloroplasts? -Both mitochondria and chloroplasts contain DNA and ribosomes. -Both mitochondria and chloroplasts are responsible for predominantly oxidative metabolic processes. -Both mitochondria and chloroplasts consume oxygen and produce carbon dioxide. -Mitochondria likely evolved from ancient endosymbiotic prokaryotes, but chloroplasts did not.

Both mitochondria and chloroplasts contain DNA and ribosomes.

A nitrogenous base is indicated by the letter _____.

C

Choose the letter that indicates the organelle that contains most of a cell's DNA.

C

Which of the following is an illustration that protein tertiary structure is NOT strictly dependent on protein secondary structure and vice versa?

Fibrous proteins are dominated primarily by secondary structure and have little to no tertiary structure.

The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.

C

Which of these is(are) pyrimidines?

C, D, E

_____ are surface appendages that allow a bacterium to stick to a surface.

Fimbriae

Cellulose belongs to which of the following groups of macromolecules? -proteins -lipids -carbohydrates -nucleic acids -none of these

Carbohydrates

What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?

Cell Wall

Which of the following statements does NOT correctly validate the three strands that compose modern cell biology? -Cellular structure arises from the combined structures of the macromolecules that compose cells. -Cellular DNA contains information about the structure and function of cellular proteins. -Mutations in the cellular DNA can compromise cellular and macromolecular structure and function. -All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.

Cellular structure arises from the combined structures of the macromolecules that compose cells. Cellular DNA contains information about the structure and function of cellular proteins. Mutations in the cellular DNA can compromise cellular and macromolecular structure and function. All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.✔

Which of these is NOT a component of the cell cytoskeleton? -microtubule -cellulose fibril -microfilament -intermediate filament

Cellulose Fibril

Which of these provides the cell with structural support?

D

The letter A indicates _____.

DNA double helix

Which of these is a difference between a DNA and an RNA molecule?

DNA is double-stranded, whereas RNA is single-stranded.

In eukaryotic cells DNA has the appearance of a _____.

Double Helix

Which of these is the double membrane that encloses the nucleus?

E

The tendency of an atom to pull electrons toward itself is referred to as its _____.

Electronegativity

True or false? Large proteins containing a nuclear localization signal (NLS) bind to the nuclear pore and enter the nucleus without any expenditure of energy.

False

Which of the following is true of glycolipids? -Fructose and sucrose are often part of glycolipids. -Usually more than 10 sugar units are attached to the glycolipid. -Glycolipids are usually found on the exterior surface of the plasma membrane. -Glycolipids are found in plastids and are used to store energy. -Glycolipids contain steroids.

Glycolipids are usually found on the exterior surface of the plasma membrane.

The brackets are indicating a(n) _____ bond.

Hydrogen

What name is given to the bond between water molecules?

Hydrogen

The secondary structure of a protein results from _____.

Hydrogen Bonds

The two strands of a DNA double helix are held together by _____ that form between pairs of nitrogenous bases.

Hydrogen Bonds

Many cell organelles, most notably the nucleus, are anchored by _______, which are assembled from a diverse class of proteins.

Intermediate Filaments

The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the...

Intermediate Filaments

Which of these statements is NOT true of the nucleolus? -It contains a nucleolus organizer region. -It synthesizes rRNA. -It contains fibrils of rDNA. -It is connected to the nucleus via nuclear pores.

It is connected to the nucleus via nuclear pores.

For a double-stranded DNA molecule in which 40% of the bases are either G or T, what can you conclude about its content of the base A?

It is impossible to determine.

During muscle contraction, myosin cross bridges attach to which active sites?

Microfilaments

The extension of pseudopodia in amoeba is due to the regulated assembly and destruction of _______.

Microfilaments

Centrosomes are sites where protein dimers assemble into ___.

Microtubules

In Eukaryotic flagella, the fibers that slide past one another due to the activity if dynein proteins are

Microtubules

Which of these are hollow rods that shape and support the cell?

Microtubules

Which of these organelles carries out cellular respiration?

Mitochondrion

Which of the following is a basic principle of macromolecular assembly?

Monomers activated by ATP are added to only one end of a polymer by condensation.

Based on the nature of the interaction between DNA and histones, what is the most likely requirement for all DNA-binding proteins?

Most DNA-binding proteins would have a strong positive charge.

What type of bond joins the monomers in a protein's primary structure?

Peptide Bond

Tertiary structure is NOT directly dependent on _____.

Peptide Bonds

Which of the following does NOT accurately highlight limitations to using in vitro, in vivo, and in silico systems in applying the scientific method in cell biology? -It is impossible to predict and estimate all necessary factors when programing an in silico experiment. -It is difficult to control variables when using in vivo systems. -None of the three systems (in vitro, in vivo, and in silico) can be used to design controlled experiments. -It is difficult to translate in vitro data to whole-organism biology.

None of the three systems (in vitro, in vivo, and in silico) can be used to design controlled experiments.

Where is a bacterial cell's DNA found?

Nucleoid Region

Nucleoplasmin is a nuclear protein. This protein was divided into two segments and linked to the same large cytoplasmic protein, generating two fusion proteins.After injecting these fusion proteins into a cell, one of the proteins was found in the nucleus and the other in the cytoplasm. Which of the following conclusions can be drawn from these results?

Only one of the two fusion proteins possesses a nuclear localization signal.

Viruses differ from cells because viruses do NOT, under any circumstances, have __________.

Organelles

A small protein (molecular weight = 25,000 daltons) is injected into a cell and observed in the nucleus a short time later. What type of transport has taken place?

Passive Transport

Which of the following is a logical reason for NOT considering phospholipids as true macromolecules/monomers? -Phospholipids are not synthesized from monomers that meet the qualities of being small, water-soluble, organic molecules. -Phospholipids are amphipathic, and monomers for macromolecules cannot be amphipathic. -Phospholipids do not form larger structures. -All of the other answer choices are logical reasons for not considering phospholipids as true macromolecules/monomers.

Phospholipids are not synthesized from monomers that meet the qualities of being small, water-soluble, organic molecules.

Drag the correct description under each cell structure to identify the role it plays in the plant cell. Plant Cell Wall, Central Vacuole, Chloroplast, Mitochondrion, and Golgi Apparatus

Plant Cell Wall: Strong, protective structure made from cellulose fibrils Central Vacuole: Regulates cytoplasm composition, creates internal pressure, and stores cell compounds Chloroplast: Makes sugar by converting light energy into chemical energy Mitochondrion: Produces chemical energy (ATP) that can power the cell Golgi Apparatus: Modifies and packages proteins

Plant cells and animal cells share many of the same structures, but each type of cell also has unique structures. In this activity, you will indicate which cell structures are found only in plant cells, only in animal cells, or in both plant and animal cells.

Plant Cell: Cell Wall, Central Vacuole, Chloroplast Animal Cell: Centriole Both: Mitochondrion, Nucleus, Plasma Membrane, Golgi Apparatus, Endoplasmic Reticulum, Cytoskeleton

The _____ is a selective barrier, regulating the passage of material into and out of the cell.

Plasma Membrane

The unequal sharing of electrons within a water molecule makes the water molecule _____.

Polar

In this molecule, what type of bond is found between the oxygen and hydrogens?

Polar Covalent

___________ structure is the sequence of amino acids in a protein.

Primary

Determine whether each term describes the primary, secondary, or tertiary structure of proteins (or forces relating to the primary, secondary, or tertiary structure of proteins). -Disulfide Bonds -Ionic Bonds -Peptide Bond -Beta-Pleated Sheet -Van der waals interactions -Alpha Helix -Hydrophobic Reactions

Primary: Peptide Bond Secondary: Alpha Helix & Beta-Pleated Sheet Tertiary: Disulfide Bonds, Van der waals interactions, Ionic Bonds, & Hydrophobic Reactions

Which of the following statements is true? -Fatty acids with 24 carbons are most common. -Unsaturated fatty acids are usually branched. -Saturated fatty acids have no double bonds between carbons. -Hormones are unsaturated fatty acids. -Fatty acids are synthesized by the stepwise addition of three carbon units.

Saturated fatty acids have no double bonds between carbons.

Two fundamental types of cells are known to exist in nature: prokaryotic cells and eukaryotic cells (like the one shown in the Tour of an Animal Cell animation). Both prokaryotic and eukaryotic cells carry out all of the processes necessary for life, but they differ in some important ways. In this activity, you will identify which cell structures are found only in prokaryotic cells, only in eukaryotic cells, or in both types of cells.

Prokaryotic: Nucleoid Eukaryotic: Lysosome, Mitochondria, Nucleolus Both: Flagella, Plasma Membrane, Ribosomes

_________ structure is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.

Quaternary

DNA is different from RNA in that

RNA contains an additional oxygen atom on the ribose sugar.

_____ are the sites of protein synthesis.

Ribosomes

Which of the following is a characteristic common to all ribosomes from organisms of the three domains of life? -Ribosomes from organisms of the three domains contain proteins and rRNA and catalyze protein synthesis. -Ribosomes from organisms of the three domains can be found on the surface of the rough endoplasmic reticulum. -All ribosomes are of the same size. -Ribosomes from organisms of the three domains have the same number of protein subunits.

Ribosomes from organisms of the three domains contain proteins and rRNA and catalyze protein synthesis.

Which of these manufactures cellular membranes by adding membrane proteins and phospholipids to its own membrane?

Rough Endoplasmic Reticulum (Rough ER)

__________ structure describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain.

Secondary

What is a potential limitation of GFP?

Short wavelengths of excitation light can damage the cell's DNA.

Where is calcium stored?

Smooth Endoplasmic Reticulum (Smooth ER)

What is this an image of? (Purple loops in a curly shoe-lace formation)

Supercoils

_________ structure is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids

Tertiary

Which of the following statements is the most accurate reflection of native protein tertiary structure? -The protein tertiary structure results from all amino acids in a protein adopting secondary structure. -Tertiary structure is the overall three-dimensional shape of a protein. It is determined by hydrogen bonds, interactions between hydrophobic R groups, ionic bonds between R groups, van der Waals interactions, and disulfide bridges. -Protein tertiary structure is present only to allow for the formation of protein quaternary structure. -Protein tertiary structure is present only to allow for the formation of multiple functional domains.

Tertiary structure is the overall three-dimensional shape of a protein. It is determined by hydrogen bonds, interactions between hydrophobic R groups, ionic bonds between R groups, van der Waals interactions, and disulfide bridges.

What is important in cloning the GFP cDNA into the vector?

The GFP cDNA is in the same reading frame as the target protein.

Cellulose, chitin, and the polysaccharide that makes up the cell walls of many bacteria are the structural polysaccharides, whereas starch and glycogen are the main storage polysaccharides. What must be true about these two classes of polysaccharides?

The bonds of storage polysaccharides are less stable than the bonds of structural polysaccharides.

What is the most likely mechanism of cell death if a culture of cells is exposed to a toxin that compromises the form and function of the nucleolus?

The cells will likely die due to a decline in protein synthesis.

The addition of some amphipathic molecules (such as detergents) to water decreases the surface tension of water. Which of the following must be true? -Water is becoming more polar. -The intermolecular hydrogen bonding of water is being weakened by the detergent. -The specific heat of water is increasing. -The boiling point of water is increasing.

The intermolecular hydrogen bonding of water is being weakened by the detergent.

Which of the following statements about the nuclear envelope is false? -The nuclear envelope is continuous with the Golgi apparatus. -The nuclear envelope is composed of two lipid bilayers. -Nuclear pores are made up of a group of proteins that are collectively called the nuclear pore complex. -Molecules pass into and out of the nucleus through nuclear pores.

The nuclear envelope is continuous with the Golgi apparatus.

Which of the following statements about DNA structure is true? -The nucleic acid strands in a DNA molecule are oriented antiparallel to each other, meaning they run in opposite directions. -Nucleic acids are formed through phosphodiester bonds that link nucleosides together. -The pentose sugar in DNA is ribose. -Hydrogen bonds formed between the sugar‑phosphate backbones of the two DNA chains help to stabilize DNA structure.

The nucleic acid strands in a DNA molecule are oriented antiparallel to each other, meaning they run in opposite directions.

You are investigating the structure of the seeds of a newly discovered tropical plant. There is storage material inside the seed. You treat the seed with peptidase (an enzyme that breaks peptide bonds), glycoside hydrolases (an enzyme that breaks β glycosidic bonds), and amylase (an enzyme that breaks α glycosidic bonds). Only the amylase appears to dissolve the storage material in the seed. What does this tell you about the identity of the storage material?

The seed contains starch to store carbon and energy.

True or False: Guanine and adenine are purines found in DNA.

True

Which of the following is NOT true concerning the six classes of lipids? -One or more of the lipid classes can be used by the cell as energy storage molecules. -They are responsible for expression of genetic information. -They can be involved in transmission of signals within a cell. -They participate in membrane structure.

They are responsible for expression of genetic information.

Which of these nitrogenous bases is found in DNA but not in RNA?

Thymine

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.

Thymine...... Cytosine

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.

Thymine....... Cytosine

In experiments to test whether a protein can enter the nucleus, why would proteins be labeled with fluorescent molecules?

To make the proteins easy to see

__________ serve as hydrophilic channels through hydrophobic membranes, or they act as carriers of specific solutes.

Transport Proteins

Which of the following is INCONSISTENT with the cellular basis of life? -Cellular function is intimately linked to cellular structure. -Viruses are living, acellular parasites. -The nuclear and mitochondrial DNA of a cell contains all of the information necessary for cellular reproduction. -All anatomical structures and physiological processes of an organism are consequences of emergent properties of cellular structures and cellular processes.

Viruses are living, acellular parasites.

A scientific hypothesis is __________.

a testable explanation of a natural phenomenon

A discrete, locally folded unit of protein tertiary structure usually having a specific function best describes __________.

a Domain

Radioisotopes have been important in the study of biochemical pathways because they __________.

allow scientists to trace the fate of specific molecules

The term amphipathic describes the characteristic of some molecules that have ________.

both a polar and a nonpolar region

Animal Cell: Drag the labels on the left onto the diagram of the animal cell to correctly identify the function performed by each cellular structure.

chapter 1/4 # 14 Part A

Identify three possible components of a DNA nucleotide. -cytosine, phosphate group, ribose -guanine, phosphate group, ribose -adenine, phosphate group, ribose -deoxyribose, phosphate group, thymine -deoxyribose, phosphate group, uracil -cytidine, phosphate group, ribose

deoxyribose, phosphate group, thymine

For which of the following may GFP fusion technology NOT be a good technique to use? -for soluble proteins found in the cytosol -for proteins restricted to the nucleus -for target proteins whose structure is altered by a GFP fusion -for transmembrane proteins with cytoplasmic domains

for target proteins whose structure is altered by a GFP fusion

Each water molecule is joined to _____ other water molecules by ____ bonds.

four..... hydrogen

The pointer is indicating the virus's _____.

genome

GFP fusion technology would be best used for which of the following experiments?

localizing the compartment where Golgi proteins are found

Fatty acids are ________; they function in the cell as ________.

long, unbranched hydrocarbon chains with a carboxyl group at one end; building blocks for other lipids

What is this an image of? (Purple spirals in S shapes up and down)

loops

Which of the following groups of organelles contain acid hydrolases, catalase, and detoxifying enzymes for drugs, respectively? -lysosome, peroxisome, smooth endoplasmic reticulum -mitochondria, rough endoplasmic reticulum, smooth endoplasmic reticulum -lysosome, mitochondria, Golgi complex -nucleus, peroxisome, rough endoplasmic reticulum

lysosome, peroxisome, smooth endoplasmic reticulum

Phosphatidyl ethanolamine is a major class of membrane phospholipid. Therefore, it is __________.

made up of a polar head and two nonpolar tails

Which technique discussed in the textbook would allow a cell biologist to determine the size and composition of an individual protein?

mass spectrometry

Ribosomal subunits are manufactured by the _____.

nucleolus

Which type of microscope can detect density differences and thereby see organelles in living cells?

phase contrast

Which of the following is not a steroid? -phenylalanine -estradiol -cortisol -aldosterone -testosterone

phenylalanine

A nucleotide is composed of a(n) _____.

phosphate group, a nitrogen-containing base, and a five-carbon sugar

The 5' end of a DNA molecule can be chemically distinguished from the 3' end because there is a(n) ________ group at the 5' end and a(n) ________ group at the 3' end.

phosphate; hydroxyl

The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.

plasma membrane

What is the function of a bacterium's capsule?

protection

Alteration of histones by addition of methyl and acetyl groups to particular amino acids

results in the remodeling of chromatin that can activate or inhibit gene expression.

In a bacterium, where are proteins synthesized?

ribosomes

Which of these illustrates the secondary structure of a protein?

secondary

One difference between rough and smooth ER is that __________.

smooth ER is involved in drug detoxification

Which experimental finding was critical in establishing the idea that RNA may have been the first informational molecule?

the discovery of ribozymes

The function of triglycerides is

to store energy

Viral DNA makes mRNA by the process of _____.

transcription

Chapter 3 Proteins and Nucleic Acids # 15 Part A & B

unavailable because fill in the blank picture

Chapter 3 Proteins and Nucleic Acids #14 Part D

unavailable because its a fill in the blank picture question

Cells expressing the GFP fusion protein will show florescence __________.

where the GFP fusion protein is localized in the cell