AP Bio Exam Review

STUDY
PLAY
A cell's capacity to acquire and use energy for building and breaking apart molecules is called
metabolism
The main energy carriers in cells are
ATP molecules
______ are the smallest units that have complex organization, show metabolic activity, reproduce and exhibit other characteristics of life
cells
The plasma membrane
surrounds an inner region of cytoplasm and separates internal cell events from the environment
Unlike eukaryotic cells, prokaryotic cells
do not have a nucleus
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.
Plant cells but not animal cells have
a cell wall
The cytomembrane system does not include:
chloroplasts
The _______ is responsible for cell shape, internal structural organization, and cell movement.
cytoskeleton
Which structure is the site of the synthesis of proteins that may be exported from the cell?
rough ER
An animal secretory cell and a photosynthetic leaf cell are similar in all the following ways except
they both have chloroplasts
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
Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?
gap junctions
Cell membranes consist mainly of a
phospholipid bilayer and proteins
The most abundant components of cell membranes are
phospholipids and proteins
In a lipid bilayer, the _____ of lipid molecules are sandwiched between their _______.
hydrophobic tails, hydrophilic heads
Most membrane functions are carried out by
proteins
Internal cell membranes as well as the plasma membrane incorporate
transport proteins, receptor proteins, adhesion proteins, recognition proteins
When a cell is placed in a hypnotic solution, water tends to
move into the cell
The direction in which a solute diffuses from one region to another will not be influenced by
the pressure of other solutes
________ can diffuse across a lipid bilayer
oxygen and CO2
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
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
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
In a hypotonic solution an animal cell will
lyse (explode)
Which of the processes can move a solute against its concentration gradient?
active transport
Cholesterol enters cells via
receptor-mediated endocytosis
The presence of cholesterol in the plasma membranes of some animals
enables the membrane to stay fluid more easily when the cell temperature drops
All of the following are functions of integral membrane proteins except:
transport, signal transduction, protein synthesis, cell-cell recognition, intercellular joining.
protein synthesis
All of the following membrane activities require ATP energy except
facilitated diffusion
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
Substances move into and out of the cells by crossing the
cell membrane
________ cannot diffuse across the lipid bilayer of the plasma bilayer.
ethanol
Three classes of proteins essential for membrane functions are _________ proteins.
transport, receptor, recognition
_________ are membrane proteins that binds hormones and other substances that can trigger changes in cell behavior or metabolism.
receptor protein
Paracrine signaling
involves secreting cells acting on nearby target cells by releasing local regulators
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"
The three stages of cell signaling are
transduction, reception, communication
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
Tyrosine-kinase receptors on the cytoplasmic side
transfer a phosphate group from tap to tyrosine on a substrate protein
Ion-channel receptors
respond to
Signal transduction pathways
are dependent on conformational changes in protein kinases
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
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
Which of the following are widely used as second messengers in signal transduction pathways?
calcium ions and cAMP
All of the following are true of cell communication systems except
most signal receptors are bound to the outer membrane of the nuclear envelope
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
_________ are specialized protein complexes that create an aqueous or between the cytoplasm of two adjacent cells.
gap junctions
How do most hydrophobic chemical messengers get transported to a target cell?
they bind to carrier proteins in the blood
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
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
Animals use ______- cell-to-cell communication to send signals between in
gap junction
Scientists hypothesize that cell signaling in animals evolved from
ancestral mechanism that unicellular organisms use to sense their environment
Cyclic AMP(cAMP)
directly interacts with G proteins
G-proteins function in cell signaling by changing structure as a result of
GDP/GTP exchange and GTP hydrolysis
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
Genes that encode proteins that are always needed are called:
constitutive genes
How does the lactose repressor block transcription of the lactose operon?
by binding to the operator
Inducible genes are usually actively transcribed when:
the molecule degraded by the enzyme is present in the cell
Repressible genes are usually actively transcribed when:
the supply of the end product formed by the enzymes encoded by these genes is low
Bacterial enzymes that are a part of a rarely used catabolic pathway are usually organized into a ________
inducible operon
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
Catabolite activator protein:
increases the affinity of the promoter region for RNA polymerase
cAMP levels decrease when ________. The results in _________ of CAP.
glucose levels increase; inhibition
In the lac operon, cAMP binds to:
catabolite activator protein
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
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
Temporal gene regulation refers to which of the following circumstances?
certain genes are induced only at a particular point in the life cycle
DNA sequences that are methylated by a cell are usually genes that:
are inactive
The rate of eukaryotic transcription after initiation is affected by:
enhancers
A TATA box is seen in________ cells and is the site where ________
eukaryotic; RNA polymerase binds
DNA sequences called _______ increase the rate of RNA synthesis after initiation of transcription.
enhancers
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.
Which of the following statements concerning leucine zipper proteins is FALSE?
they contain loops held together by zinc ions
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
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
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
Increasing the stability of a particular mRNA _______ the expression of that gene.
increases
Enzymes that alter another protein or enzyme's activity by attaching a phosphate group called:
kinases
Splicing together DNA from 2 different organisms is called:
recombinant DNA technology
What purpose do restriction enzymes play in bacterial cells?
restriction enzymes attack bacteriophage DNA when it enters the cell
Transformation is process whereby
plasmids are transferred into bacterial cells
Which DNA sequence below would be a palindromic sequence?
AGCGCT
"Sticky ends" are:
the single-stranded ends of a DNA segment created by some restriction enzymes.
DNA ligase links two______ DNA fragments by________ bonds.
linear; covalent
In producing a genomic library, human DNA and plasmid DNA must be treated with:
the same restriction enzymes
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
The amplification of recombinant plasmids occurs by:
the process of growth and division of the host cell.
In polymerase chain reaction technology, the two strands of DNA are separated by:
heating them
Refer to Figure 15-2. The darker sections of the original molecule, labeled as 1, represent:
exons
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
_________ is a technique that can be used to separate DNA molecules on the basis of their size.
electrophoresis
The major problem with polymerase chain reaction is:
contamination
Southern blotting is a process where_______ is transferred from a gel to a ________ where a probe can be applied.
protein; nitrocellulose filter
The presence of detectable variation in the genomes of different individuals of a population is termed:
polymorphism
The chain termination method is used in:
DNA sequencing
The area of genomics that is concerned with mapping and sequences genomes is called________ genomics.
structural
If a protein-coding gene is identified, its function can be studied by using RNA interference to _________.
turn the gene off
Gene targeting:
involves the excision of the target genes, which are then "knocked out"
Gene targeting is currently being used in all of the following applications except:
forensic science
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
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.
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
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
The FBI currently determined an individual's DNA profile using:
13 STR markers
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
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
Transgenic organisms are used to aid studies of:
genetic diseases, gene expression, immune system function and viral diseases
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
________ is an example of a plant that is genetically modified to produce high quantities of B-carotene of conversion to vitamin A.
rice
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
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
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
the first experimenters to use Griffith's transformation assay to identify the genetic material were:
Avery, MacLeod, and McCarty
which of the following statements about DNA is false?
DNA is only found in eukaryotic cells
the bacteriophages used in Alfred Hershey's and Martha Chase's experiments showed that:
DNA was injected into bacteria
the two molecules that alternate to form the backbone of a polynucleotide chain are:
sugar and phosphate
chargaff determined that DNA from any source contains about the same amount of guanine as ______
cytosine
____ used x-ray diffraction to provide images of DNA
franklin
x-ray crystallography showed that DNA:
was a helix
_____ determined the structure of the molecule DNA
watson and crick
the information carried by DNA is incorporated in a code specified by the:
specific nucleotide sequence of the DNA molecule
why is DNA able to store large amounts of information?
its nucleotides can be arranged in a large number of possible sequences
the portion of the molecule in box 5 of figure 12-1 is:
a phosphate
in figure 12-1, the portion of the molecule in box ____ is a pyrimidine
1
the portion of the molecule in box 3 of figure 12-1 is:
A purine
hydrogen bonds can form between guanine and ____ and between adenine and _____
cytosine; thymine
two chains of DNA must run in ____ directions and must be ______ if they are to bond with each other
antiparallel; complementary
which of the following nucleotide sequence represents the complement to the DNA strand
3'-TCTAGGC-5'
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
which of the following best describes semiconservative replication?
a DNA molecule consists of one parental strand and one new strand
the final product of DNA replication is:
two DNA molecules; each of which contains one new and one old DNA strand
if DNA replication rejoined 2 parental strands, it would be termed:
conservative
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
which of the following cause the unwinding of the DNA double helix?
DNA helicase
a replication fork:
is a Y-shaped structure where both DNA strands are replicated simultaneously
in replication, once the DNA strands have been separated, reformation of the double helix is prevented by:
single-strand binding proteins
which of the following adds new nucleotides to a growing DNA chain?
DNA polymerase
why does DNA synthesis only proceed in the 5' to 3' direction?
because DNA polymerase can only add nucleotides to the 3' end of a polynucleotide strand
the 5' end of each Okazaki fragment begins with:
a separate RNA primer
primase is the enzyme responsible for:
making short strands of RNA at the site of replication initiation
the DNA strand that is replicated smoothly and continuously is called then:
leading strand
in DNA replication, the lagging strand:
is synthesized as a series of Okazaki fragments
Okazaki fragments are joined together by:
DNA ligase
how is the chromosome of a bacterial cell replicated?
the circular DNA molecule is replicated from one origin of replication bidirectionally
refer to figure 12-2. The correct designation for the DNA strand labeled C is:
none of these
refer to figure 12-2. The segments labeled F are responsible for
initiating DNA synthesis
refer to figure 12-2. the enzyme represented by the letter D is responsible for:
linking short DNA segments
refer to figure 12-2. the structures represented by the letter E are called:
Okazaki fragments
which of the following statements concerning nucleotide excision repair is FALSE?
it is a type of mismatch repair
_____, the ends of eukaryotic chromosomes, shorten with every cell replication event
telomeres
when cultured human cells were infected with a virus that carried the genes that coded for a subunit of telomerase:
the cells underwent more cell divisions than normal
cancer cells differ from noncancerous cells in that:
they have elevated levels of telomerase, they are virtually immortal, they have the ability to resist apoptosis, they can maintain telomere length as they divide
Linus Pauling demonstrated that:
the structure of hemoglobin was altered by a mutation of a single gene
RNA differs from DNA in all the following except:
RNA is a larger molecule then DNA
ribose differs from deoxyribose by having:
an extra hydroxyl group
uracil forms a complementary pair with ___ in RNA and ____ in DNA
adenine; adenine
RNA synthesis is also known as:
transcription
all RNA except for ___ is made from DNA
tRNA, mRNA, rRNA, snRNA
the codon is found in the:
mRNA
which of the following serves as an "adapter" in protein synthesis and bridges the gap between mRNA and proteins?
tRNA
during protein synthesis, ribosomes:
attach to the mRNA molecule and travel along its length
the portion of the molecule in figure 13-2 that contains the anticodon is
3
refer to figure 13-2. The portion of the molecule labeled 5 is:
the attached amino acid
how is the 4-letter language of nucleic acids converted into the 20-word language of amino acids?
the 4 nucleic acid bases combine in 3-letter sequences that define different amino acids
one of the mRNA codons specifying the amino acid leucine is 5'-CYA-3'. Its corresponding anticodon is:
3'-GAU-5'
initiation of transcription requires:
a promoter sequence
why is only one strand of DNA transcribed into mRNA?
because transcribing both DNA strands would produce different amino acid sequences
refer to figure 13-3. The component labeled B is:
RNA polymerase
the process illustrated in figure 13-3 is:
transcription
aminoacyl-tRNA synthetases ____ link ____ to their respective tRNA molecules
covalently; amino acids
the tRNA:
must be recognized by ribosomes, must have an anticodon, must have an attachment site for the amino acid, must be recognized by a specific aminoacyl-tRNA synthetase that adds the correct amino acid
in all organisms, the AUG codon codes for:
the initiation of translation
translocation is the process whereby the ____ moves in order to place tRNA bound to the growing polypeptide chain in the ___ site; thereby freeing the _____ site for a new aminoacyl-tRNa
ribosome; P; A
following peptide bond formation between the amino acid in the A site on the ribosome and the growing polypeptide chain, the tRNA in the A site:
moves to the P site of the ribosome
if a human gene mRNA were placed into a cell of yeast, it would be:
translated into the protein that is found in humans
translocation in translation requires
energy supplied by GTP
a mRNA "5' cap"
protects newly synthesized mRNA from degradation
interrupted coding sequences include long sequence of bases that do not code for amino acids. These noncoding sequence, called ______, are found in ____ cells
introns, eukaryotic
a gene can now be defined as
a DNA sequence that carries information to produce a specific RNA or protein product
a mutation that replaces one amino acid in a protein with another is called a ______ mutation
missense
substitution of one base pair for another can result in a ____ mutation that results in the conversion of an amino acid specifying codon to a termination codon
nonsense
frameshift mutations result from:
the insertion or deletion of one or two base pairs
a bacterial chromosome consists of
a circular DNA molecule many times larger then the cell
eukaryotic chromosomes consist of
linear DNA molecules complexed with postively charged histone proteins
nucelosomes are best described as
eukaryotic DNA associated with histone proteins
nucleosomes are organized into large coiled loops in visible chromosomes by
scaffolding proteins
the cell cycle of a typical somatic cell consists of _ and M phase
interphase
the M phase of the cell cycle involves two main processes
mitosis and cytokinesis
one nerve cells become mature, they dont usually undergo cell division. Based on your knowledge of the cell cycle, you would predict that mature nerve cells become arrested in the _ of the cell cycle
G0 phase
chromosomes are duplicated during _ of the cell cycle
S phase
which of the following represents the sequence of events during mitosis?
prophase-metaphase-anaphase-telophase
if a cell is in G2
it has twice the amount of DNA present in a telophase nucleus
during prophase, _ is compacted into visible chromosomes
chromatin
the _ is responsible for the separation of the chromosomes during _ of mitosis
mitotic spindle, anaphase
_ contain identical DNA sequence and are held together by _ during mitosis
sister chromatids, centromeres
the mitotic spindle is made of
microtubules
the kinetochore serves which of the following functions?
kinetochore attach to microtubules during mitosis
all of the following events occur during premetaphase except
the duplicated chromosomes become visible with the light microscope
a cell is in metaphase if
the chromosomes are aligned at the midplane of the cell
duplicate centrioles move to opposite poles of a dividing _ cell during _ of the cell cycle
animal, prophase
the chromosome makeup of an individual organism is called a
karyotype
cytokinesis in animal cells involves contraction of a ring of _ microfilaments
actin plus myosin
cytokinesis in plant cell mitosis occurs initially by the formation of a
cell plate
if a cell is dividing by binary fission then you know that:
the cell is prokaryotic
to prevent disastrous consequences, the eukaryotic cell cycle is controlled by
a series of cell cycle checkooints
which of the following statements concerning the cell cycle is false
M-Cdk inhibits mitosis
the correct number of chromosomes is maintained during sexual reproduction by
meiosis, which reduces the chromosome number by half
animal cells are stimulated to divide by mitosis by
growth factors
if meiosis did not occur in sexually reproducing organisms, then
chromosome number would double in each generation
what evolutionary advantage is provided by sexual reproduction
increased genetic diversity
most human somatic cells are
diploid
homologous chromosomes undergo synapsis during
prophase 1
during prophase 1 of meiosis, homologous chromosomes lie side by side. this phenomeon is known as
tetrad formation
during which phase does crossing- over occur?
prophase I
a zygote contains the _ complement of chromosomes
diploid
in a human cell at prophase I, there are _ tetrads
23
an animal with a diploid number of 36 chromosomes will have _ chromosomes in its gametes and _ chromosomes in its somatic cells
18;36
during prophase I, each chiasma represents
a site of crossing- over
during which of the following stages of meiosis do the sister centromeres separate
anaphase II
the source of genetic variation during meiosis are
crossing-over and the random assortment of maternal and paternal chromosomes
which of the following events does not occur during meiosis I ?
separation of sister chromatids
the formation of female gametes is termed
oogenesis
which of the following are produced by meiosis?
polar bodies, animal eggs and sperm, plant spores
mating a true-breeding pink rose will produce:
only plants with pink roses
the physical appearance of an organism for a given trait is termed:
phenotype
the term "dominant" means that
one allele can mask the expression of another in a hybrid
_ are alternative forms of a gene that govern the same feature, such as eye color, and occupy corresponding positions on homologous chromosomes
alleles
Mendel's principle of segregation states that
alleles separate from each other from forming gametes
using standards conventions for naming alleles, which of the following pairs is correct?
tt- homozygous
a pear plant with the genotype Aa can produce gametes containing:
either A or a
the separation of alleles of a gene takes place during:
anaphase I of meiosis
the physical location of a particular gene on a chromosome is called:
a locus
which of the following represents the possible genotypes resulting from a cross between an individual homozygous (BB) and one heterozygous (Bb) individual?
BB and Bb
Mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of>
a test cross
the genotype for a pea plant that is homozygous recessive for both height and pea color would be:
ttyy
the height of pea plants from a cross between parent plants heterozygous for height, in which tall is dominant, would be:
3 tall: 1 short
what is the probability that two lizards that are heterozygous for stripes on their tails (Ss) will produce an offspring that is homozygous for no strips (ss)?
1/4
in humans, assume that the allele for brown eyes is dominant and the allele for blue eyes is recessive. If two brown-eyed individuals have a child with blue eyes, that means:
both parents are homozygous for brown eyes
a couple has already had 3 girls with cystic fibrosis, and were hoping to have a normal child for their fourth. What are the chances that the fourth child will be a normal allele?
3/8
the principle of independent assortment is not true for:
linked genes
an organism with the genotype of AaXx can produce gametes containing ______ if the two genes are unlinked.
either AX, Ax, aX, ax
the offspring of two heterozygous gray-bodied, normal-winged flies should be 50% gray bodied/ normal wings (BbRr) and 50% black bodied/ vestigial wings (bbrr) because these alleles are linked. If a small number, say 15%, of the offspring are instead black-bodied with normal wings, this is most likely the result of
crossing-over
the probability that two genes will be separated by crossing-over is related to:
the distance between the two gametes on the chromosome
a lizard with a striped tail is crossed with one having a spotted head, producing normal looking lizard progeny. What progeny would be expected to be produced by mating these progeny with each other, if the genes conferring stripes and spots were on different chromosomes?
9 normal: 3 striped: 3 spotted: 1 striped and spotted
in genetics, map units express the distance between:
two loci on a chromosome
the sex of most mammals, birds, and insects is determined by:
sex chromosomes
why is color blindness more common in males than in females ?
because females would have to receive two copies of the recessive color blindness gene to actually express the trait, because a male only needs to receive one, because it is an X-linked trait
what are the possible genotypes of a female child from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics?
x^Hx^H or x^Hx^h
a barr body in a mammalian female cell represents
an inactivated X chromosome
calico cats are never male because
two different X chromosomes are needed for the expression of the calico phenotype
when certain medium height hybrid plants were crossed, they produced offspring that were dwarf, medium, and tall in a ratio of 1:2:1. this is an example of:
incomplete dominance
what are the possible phenotypes of the children if the mothers genotype is I^Ai for blood type and the father is I^Bi
A,B,AB,O
a diploid individual has a maximum of ____ different alleles for a particular locus.
two
a particular gene that controls seed coat color in peas also determines the susceptibility of these peas to a particular disease. This situation is referred to as:
pleiotropy
breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs intermixed. This is an example of:
codominance
a gene that affects, prevents, or masks the expression of a gene at another locus is a(n) ____ gene
epistatic
_____ refers to multiple independent pairs of genes having similar and additive effects of the same characteristic
polygenic inheritance
the range of phenotypic possibilities that can develop from a certain dog genotype under different environmental conditions is called the:
norm of reaction
Which four elements make up approximately 96% of living matter?
carbon, hydrogen, nitrogen, oxygen
Which of the following is a trace element that is essential to humans and other organisms?
iron
the reactive properties or chemical behavior of an atom depends on the number of
electrons in the outer valance shell in the atom
a covalent bond is one in which
outer-shell electrons are shared by two atoms so as to satisfactory fill the outer electron shells of both
what do the four elements most abundant in living organisms have in common?
they all have unpaired electrons in their valance shells
a covalent bond is most likely to be polar when
one of the atoms sharing electrons is much more electronegative than the other atom
which of the following is an example of a hydrogen bond
the bond between the H of one water molecule and the O of another water molecule
water is able to form hydrogen bonds because
the water molecule is polar
what do cohesion, surface tension, and adhesion have in common with reference to water?
all are properties related to hydrogen bonding
water's high specific heat is mainly a consequence of the
fact that water is a poor heat conductor
ice is less dense and floats in water because it is a crystalline structure held together by
hydrogen bonds only
life on earth is dependent on all properties of water as well as the abundance of water. Which property of water is probably most important for the functioning of organisms at the molecular level?
versatility as a solvent
hydrophobic substances like vegetable oil are
non-ionic or nonpolar substances that repel water
one mole (mol) of a substance is equal to
6.02 x 10^23 molecules of the substance, the molecular weight of the substance expressed in grams
the molecular weight of glucose is 180g. to make a 1 M solution of glucose, you should do which of the following?
dissolve 180g of glucose in water, and then add more water until the total volume of the solution is 1 L
if the pH of a solution if decreased from 7 to 6, it means that
concentration of H+ has increased to 10 times of what it was at pH 7, concentration of OH-has decreased 10 times of what it was at 7
buffers are substances that help resist shifts in pH by
releasing H+ in acidic solutions
recent research indicates that acid precipitation can damage life by
changing the solubility of soil minerals, altering the structures of biological molecules required for essential life processes
which type of molecule would be most abundant in a typical prokaryotic or eukaryotic cell?
water
organic chemistry is a science based on the study of
carbon compounds
which property of the carbon atom gives it compatibility with a greater number if different elements than any other type of atom?
carbon has a valence of 4
the carbon present in all organic compounds
is incorporated into organic molecules by plants, is processed into sugars through photosynthesis, is derived from CO2
what is the reason why hydrocarbons are not soluble in water?
the C-H bond is nonpolar
observe the structure of glucose and fructose. these two molecules differ in the
arrangement of carbon, hydrogen, and oxygen atoms
refer to the structure of the two molecules. these two molecules are best described as
geometric isomers
refer to structures of glucose and fructose. these two molecules are
structuran isomers
recent research suggests that side effects from Ritalin, may be caused by contamination of enantiomers, or molecules that
are mirror images of one another
a compound contains hydroxyl groups as its predominant functional group. which of the following statements is true concerning that compound?
it should dissolve in water
amino acids are acids because they possess which functional group?
carboxyl
observe the structure of the following groups of molecules. which one of the structure is an impossible covalently bonded molecule?
C because its missing a H
which molecule contains codons?
mRNA
a promoter is important because
it recruits the enzyme that produces RNA
A biofuel company finds that the yeast strain they have been using becomes less tolerant to ethanol. The company also notices that the bad yeast strain contains no dehydrogenase protein, which is involved in the ethanol tolerance and is present in a normal yeast strain. The dehydrogenase mRNA in the bad yeast strain is the same in the normal. Which might result in decreased ethanol tolerance?
Ribosomes in the bad yeast strain are not able to bind to the dehydrogenase mRNA
Gln-Ser-Ser-Lys-Gln is involved in ethanol tolerance. Which one would you use to produce the highest concentration of ethanol?
5'CAGUCGUCCAAACAA3'
Recombinant DNA technology is widely used. What would you do after the plasmid DNA and your DNA of interest are joined together to form a recombinant DNA?
add DNA ligase
Which could be joined with this bacterial DNA?:
5'AAAAG
TTTTCTTAA3'
Bacterial DNA: 5'TTAACGCCCT
GCGGGA3'
What happens during transcription?
DNA nucleotides code for genetic code
Which of the following would result from the transcription of this DNA template strand?:
3'AAGTAATTAAC5'
5'TTCATTAATTG3'
What is the amino acid sequence of the protein produced by the mRNA molecule below? 5'AUGUGCAUUGACGUG3'
Met-Cys-IIe-Asp-Val
tRNA is responsible for the
transfer of amino acids
mRNA is responsible for the
code for proteins
rRNA is
part of the ribosome
ATG is a
start codon
UGA is a
stop codon
AAA is
the code for lysine
CGA is
the code for argnine
restriction enzymes
cut DNA to produce fragments
DNA ligase
link together two DNA molecules
plasmids
are DNA delivery vectors
transformation
gets recombinant DNA into bacterial cells
Which of the following best describes a recombinant DNA?
the man-made assembly of two DNA segments
a transgenic organism is one whose genome has
a segment of DNA from another species
which molecule is likely to be produced by a restriction enzyme?
5'T CTAGA3'
3' AGATC T5'
Which one is not an essential feature of a plasmid?
can be cut by restriction enzymes
What happens during transformation?
bacterial cells absorb your DNA of interest.
what are the ten themes of biology
Evolution, Response, Structure and function, cell theory, hereditary info, regulation/homeostasis,/metabolism, emergent properties, science/society, unity and diversity, scientific inquiry
3 tenets of the cell theory
1. everything is made up of cells 2.cells come from previous cells 3. smallest unit of life
3 properties of water that make life on Earth possible
1. low specific heat 2.low density of ice 3. universal solvent
what is the best description of the science of biology
study of life
what is reflective of the phrase "the whole is better than the sum of its parts"
emergent properties
to understand genetic inheritance one must understand DNA. this is an example of ________
reductionism
what utilizes DNA as their genetic material(3)
Prokaryotes, eukaryotes, and archaea
one of the key difference between prokaryotic and eukaryotic cells is the presence of ____ cells which is lacking in ____ cells
a nucleus in eukaryotic...prokaryotic
for most ecosystems___ is the ultimate source of energy and energy leave the ecosystem in the form of _____
light...heat
what is the hierarchical organization of life from most to least inclusive
domain, kingdom, phylum, class, order, family, genus, specie
what are the two classifications of prokaryotes
domain archaea and domain bacteria
how are most unicellular eukaryotes classified
protista
A water sample from a hot vent contained a singe-celled organism that lacked a nucleus. what is it most likely classified as
archaea
you have discovered a new specie that uses starch rather than DNA as its genetic material. You have discovered a new...
domain of life
what provides evidence of the common ancestry of all life
the universality of the genetic code
natural selection
is differential reproductive success
structural isomers
compounds that have the same molecular formula but differ in the covalent arrangements of their atoms.
structural isomers example
ethanol and dimethyl ether (C2H6O)
geometric isomers
Compounds that have the same molecular formula but differ in the spatial arrangements of their atoms.
geometric isomers examples
trans 2 butane, cis 2 butane
enantiomers
molecules that are mirror images of each other
methyl group
(R-CH3)
hydroxyl group
(R-OH)
carbonyl group
C double-bonded to O
aldehyde
(R-CHO)
ketone
(R-CO-R)
carboxyl group
(R-COOH)
amino group
(R-NH2)
phosphate group
(R-PO4H2)
sulfurhydryl group
(R-SH)