AP Bio Exam Review

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phosphate group

(R-PO4H2)

sulfurhydryl group

(R-SH)

in figure 12-1, the portion of the molecule in box ____ is a pyrimidine

1

The FBI currently determined an individual's DNA profile using:

13 STR markers

which of the following nucleotide sequence represents the complement to the DNA strand

3'-TCTAGGC-5'

the portion of the molecule in box 3 of figure 12-1 is:

A purine

Which DNA sequence below would be a palindromic sequence?

AGCGCT

The main energy carriers in cells are

ATP molecules

the first experimenters to use Griffith's transformation assay to identify the genetic material were:

Avery, MacLeod, and McCarty

which of the following cause the unwinding of the DNA double helix?

DNA helicase

which of the following statements about DNA is false?

DNA is only found in eukaryotic cells

which of the following adds new nucleotides to a growing DNA chain?

DNA polymerase

The chain termination method is used in:

DNA sequencing

the bacteriophages used in Alfred Hershey's and Martha Chase's experiments showed that:

DNA was injected into bacteria

G-proteins function in cell signaling by changing structure as a result of

GDP/GTP exchange and GTP hydrolysis

which of the following best describes semiconservative replication?

a DNA molecule consists of one parental strand and one new strand

Plant cells but not animal cells have

a cell wall

the portion of the molecule in box 5 of figure 12-1 is:

a phosphate

Sodiums ions move across a membrane, through the interior of a channel protein that has received an energy boost. This is an example of

active transport

Which of the processes can move a solute against its concentration gradient?

active transport

Microfilaments are well known for their role in which of the following?

ameboid movement, formation of cleavage furrows during cell devision, contracting of muscle cells

Scientists hypothesize that cell signaling in animals evolved from

ancestral mechanism that unicellular organisms use to sense their environment

During the preparation of human genomic library, plasmids containing human DNA fragments are inserted into:

antibiotic-sensitive E.coli cells that become antibiotic-resistant if transformed

two chains of DNA must run in ____ directions and must be ______ if they are to bond with each other

antiparallel; complementary

Signal transduction pathways

are dependent on conformational changes in protein kinases

DNA sequences that are methylated by a cell are usually genes that:

are inactive

Organelles

are membrane-bound compartments, are typical of eukaryotic cells, no prokaryotic cells, separate chemical reactions in time in space, and have specific jobs within the cell.

Signaling pathways with multiple steps

are often linked by scaffolding proteins, may amplify a signal, contribute to specificity of the response and produce different results on different cells or tissues

how is a single strand of DNA able to serve as a template for the synthesis of another strand?

both the pairing of nucleotides and the breaking of hydrogen bonds

How does the lactose repressor block transcription of the lactose operon?

by binding to the operator

Which of the following are widely used as second messengers in signal transduction pathways?

calcium ions and cAMP

In the lac operon, cAMP binds to:

catabolite activator protein

Substances move into and out of the cells by crossing the

cell membrane

______ are the smallest units that have complex organization, show metabolic activity, reproduce and exhibit other characteristics of life

cells

Temporal gene regulation refers to which of the following circumstances?

certain genes are induced only at a particular point in the life cycle

The cytomembrane system does not include:

chloroplasts

Why is human blood clotting factor VIII produced by genetically engineered bacteria better to treat hemophilia type A than the clotting factor isolated from human or animal blood?

clotting factor isolated from blood can transmit infectious agents

if DNA replication rejoined 2 parental strands, it would be termed:

conservative

Genes that encode proteins that are always needed are called:

constitutive genes

The major problem with polymerase chain reaction is:

contamination

A cell may meet the need for large quantities of a specific protein by:

continuously synthesizing the mRNA molecule that specifies that protein, increasing the half-life of the mRNA that specifies the protein, having multiple copies of the gene that codes for that protein.

chargaff determined that DNA from any source contains about the same amount of guanine as ______

cytosine

hydrogen bonds can form between guanine and ____ and between adenine and _____

cytosine; thymine

The _______ is responsible for cell shape, internal structural organization, and cell movement.

cytoskeleton

In eukaryotes, some DNA sequences act as introns in the cells of some tissues and exons in the cells of other tissues. This allows:

differential mRNA processing

The passive movement of a substance through a channel proteins as it follows its concentration gradient across a cell membrane is an example of

diffusion

Cyclic AMP(cAMP)

directly interacts with G proteins

Unlike eukaryotic cells, prokaryotic cells

do not have a nucleus

_________ is a technique that can be used to separate DNA molecules on the basis of their size.

electrophoresis

The presence of cholesterol in the plasma membranes of some animals

enables the membrane to stay fluid more easily when the cell temperature drops

DNA sequences called _______ increase the rate of RNA synthesis after initiation of transcription.

enhancers

The rate of eukaryotic transcription after initiation is affected by:

enhancers

________ cannot diffuse across the lipid bilayer of the plasma bilayer.

ethanol

A TATA box is seen in________ cells and is the site where ________

eukaryotic; RNA polymerase binds

Refer to Figure 15-2. The darker sections of the original molecule, labeled as 1, represent:

exons

All of the following membrane activities require ATP energy except

facilitated diffusion

Gene targeting is currently being used in all of the following applications except:

forensic science

Some eukaryotic DNA sequences act as introns in the cell of some tissues and exons in the cells of other tissues. This allows:

formation of different types of closely related proteins

____ used x-ray diffraction to provide images of DNA

franklin

Animals use ______- cell-to-cell communication to send signals between in

gap junction

Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?

gap junctions

_________ are specialized protein complexes that create an aqueous or between the cytoplasm of two adjacent cells.

gap junctions

Proteomics is made complicated by the fact that:

gene therapy is in its infancy, DNA sequencing requires powerful computers, the response to a drug varies with the individual, certain genes encode several different proteins.

Transgenic organisms are used to aid studies of:

genetic diseases, gene expression, immune system function and viral diseases

Why is it unlikely that genetically engineered strains of bacteria would pose a threat to the environment?

genetically engineered strains of bacteria are poor competitors of wild strains

A selectively permeable membrane containing specific concentrations of two solutions is immersed in a beaker containing four different solutions. The membrane is permeable to simple sugars but impermeable to disaccharides and polysaccharides. Which solute will diffuse into the cell?

glucose

cAMP levels decrease when ________. The results in _________ of CAP.

glucose levels increase; inhibition

In polymerase chain reaction technology, the two strands of DNA are separated by:

heating them

Hormone signaling differs from synaptic(nerve) signaling in that

hormone signaling is important for cells that are far apart whereas synaptic signaling is more "cell to cell"

In a lipid bilayer, the _____ of lipid molecules are sandwiched between their _______.

hydrophobic tails, hydrophilic heads

Increasing the stability of a particular mRNA _______ the expression of that gene.

increases

Catabolite activator protein:

increases the affinity of the promoter region for RNA polymerase

Bacterial enzymes that are a part of a rarely used catabolic pathway are usually organized into a ________

inducible operon

Paracrine signaling

involves secreting cells acting on nearby target cells by releasing local regulators

Gene targeting:

involves the excision of the target genes, which are then "knocked out"

a replication fork:

is a Y-shaped structure where both DNA strands are replicated simultaneously

Why is insulin produced by genetically engineering E. Coli cells superior to insulin obtained from animal sources?

it contains human rather than animal sequences, reducing the chances of an allergic response

In the field of the plant transgenics, the use of the bacterium Agrobacterium tumefacions has proven useful because:

it is able to transfer a plasmid into the host plant cells

why is DNA able to store large amounts of information?

its nucleotides can be arranged in a large number of possible sequences

Enzymes that alter another protein or enzyme's activity by attaching a phosphate group called:

kinases

DNA ligase links two______ DNA fragments by________ bonds.

linear; covalent

In a hypotonic solution an animal cell will

lyse (explode)

A cell's capacity to acquire and use energy for building and breaking apart molecules is called

metabolism

The method of choice to determine a DNA profile on DNA-containing forensic evidence that is old or has been damaged is:

mitochondrial DNA sequencing

All of the following are true of cell communication systems except

most signal receptors are bound to the outer membrane of the nuclear envelope

When a cell is placed in a hypnotic solution, water tends to

move into the cell

A new operon is discovered in bacterium. The control of this operon is affected by a protein that is made by another gene, and is made in an active form that binds to the DNA near the operon to prevent transcription. This is an example of _______ control.

negative

Ligand gated ion channels

open or close in response to a chemical signal, are important in the nervous system, lead to changes in sodium and calcium concentrations in cells, depend somewhat on ion gradients, or can accommodate different ion concentrations

________ can diffuse across a lipid bilayer

oxygen and CO2

Which of the following bits of the information can de inferred from the ratio of different-colored fluorescent dyes in a microarray?

patterns of gene expression, comparison of drug activity, identification of disease-causing genes and proteins

Cell membranes consist mainly of a

phospholipid bilayer and proteins

The most abundant components of cell membranes are

phospholipids and proteins

Transformation is process whereby

plasmids are transferred into bacterial cells

The presence of detectable variation in the genomes of different individuals of a population is termed:

polymorphism

All of the following are functions of integral membrane proteins except: transport, signal transduction, protein synthesis, cell-cell recognition, intercellular joining.

protein synthesis

Southern blotting is a process where_______ is transferred from a gel to a ________ where a probe can be applied.

protein; nitrocellulose filter

Most membrane functions are carried out by

proteins

_________ are membrane proteins that binds hormones and other substances that can trigger changes in cell behavior or metabolism.

receptor protein

Cholesterol enters cells via

receptor-mediated endocytosis

Splicing together DNA from 2 different organisms is called:

recombinant DNA technology

Which of the following types of processing does of eukaryotic proteins involves:

removal of a portion of the polypeptide chain from an inactive precursor of the protein

Ion-channel receptors

respond to

What purpose do restriction enzymes play in bacterial cells?

restriction enzymes attack bacteriophage DNA when it enters the cell

________ is an example of a plant that is genetically modified to produce high quantities of B-carotene of conversion to vitamin A.

rice

Which structure is the site of the synthesis of proteins that may be exported from the cell?

rough ER

in replication, once the DNA strands have been separated, reformation of the double helix is prevented by:

single-strand binding proteins

the information carried by DNA is incorporated in a code specified by the:

specific nucleotide sequence of the DNA molecule

An activator protein would have which of the following effects on an operon with a positive control mechanism?

stimulate transcription when a coactivator is bound to the allosteric site

The area of genomics that is concerned with mapping and sequences genomes is called________ genomics.

structural

the two molecules that alternate to form the backbone of a polynucleotide chain are:

sugar and phosphate

The plasma membrane

surrounds an inner region of cytoplasm and separates internal cell events from the environment

Communication among neuron and between neurons and other target cells occurs across short distances at a structure called the _____, a region where the signaling cell and the target cell are very close together.

synapse

A key difference between G-protein receptors and tyrosine-kinase receptors is

the G-protein system function more like off/on switches for cells, while the tyrosein-kinase system is more effective when cells need to regulate and coordinate a variety of activities or trigger several signal pathways at once

Refer to figure 15-2. The most significant difference between the original DNA molecule and the final product, labeled 12, is:

the lack of introns

the main reason scientists thought that proteins, rather then DNA, were the carriers of genetic material in the cell:

the large number of possible amino acid combinations

Inducible genes are usually actively transcribed when:

the molecule degraded by the enzyme is present in the cell

when a DNA molecule containing a wrong base at one location in one strand in replicated:

the mutation is copied into one of the two daughter molecules

The direction in which a solute diffuses from one region to another will not be influenced by

the pressure of other solutes

The amplification of recombinant plasmids occurs by:

the process of growth and division of the host cell.

Epinephrine binds to the same type of receptors in liver, fat and smooth muscle cells. How are such different responses produced by the same hormone?

the same receptors activate three different second messengers

In producing a genomic library, human DNA and plasmid DNA must be treated with:

the same restriction enzymes

"Sticky ends" are:

the single-stranded ends of a DNA segment created by some restriction enzymes.

The focus of gene regulation in multicellular organisms is on

the specificity of products in different tissues, operons, economizing resources at all levels, rapid turnover of RNA molecules

Repressible genes are usually actively transcribed when:

the supply of the end product formed by the enzymes encoded by these genes is low

How do most hydrophobic chemical messengers get transported to a target cell?

they bind to carrier proteins in the blood

An animal secretory cell and a photosynthetic leaf cell are similar in all the following ways except

they both have chloroplasts

Which of the following statements concerning leucine zipper proteins is FALSE?

they contain loops held together by zinc ions

The columns in Figure 15-3 represent F(for female), C (for children), and M (for male). The presence of the band marked with arrow #1 shows that:

this DNA sequence in the children is inherited from their mother

The three stages of cell signaling are

transduction, reception, communication

Tyrosine-kinase receptors on the cytoplasmic side

transfer a phosphate group from tap to tyrosine on a substrate protein

Internal cell membranes as well as the plasma membrane incorporate

transport proteins, receptor proteins, adhesion proteins, recognition proteins

Three classes of proteins essential for membrane functions are _________ proteins.

transport, receptor, recognition

A repressor protein would have which of the following effects on repressible genes with a negative control mechanism?

turn off transcription in the presence of a corepressor

If a protein-coding gene is identified, its function can be studied by using RNA interference to _________.

turn the gene off

the final product of DNA replication is:

two DNA molecules; each of which contains one new and one old DNA strand

The cotransport port protein protein that allows two different substances to pass through a membrane in the same direction is

usually associated with a proton pump usually also a biport

x-ray crystallography showed that DNA:

was a helix

in the experiment of Griffith, the conversion of nonlethal R-strain bacteria to lethal S-strain bacteria:

was an example of the genetic exchange known as transformation

_____ determined the structure of the molecule DNA

watson and crick

How does a ligand- gated channel work?

when a ligand binds to an ion channel, the channel changes conformation and the ion channel opens, allowing ions to cross the membrane


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