Term
| In protein synthysis, where does the process of transcription take place? |
|
Definition
| In the nucleus, using DNA as a template |
|
|
Term
| Which of the following bases is NOT found in mRNA? |
|
Definition
|
|
Term
| In DNA, complementary base pairing occurs between: |
|
Definition
|
|
Term
| Each "word" in the mRNA language consists of how many letters? |
|
Definition
|
|
Term
|
Definition
| produces two molecules, each of which is half new and half old DNA |
|
|
Term
| Who found DNA (deoxyribonucleic acid) in nuclei in the 1800s? |
|
Definition
|
|
Term
| Who transferred hereditary material from dead cells to live cells in the early 1900s? |
|
Definition
|
|
Term
______ and ______ separated deadly S cells (from Griffith’s experiments) into lipid, protein, and nucleic acid
components in 1940.
What was the conclusion? |
|
Definition
Avery; McCarty
-DNA is the “transforming principle” |
|
|
Term
______ and ______ experimented with bacteriophages (viruses that infect bacteria)in the 1950s.
Conclusion? |
|
Definition
Hershey; Chase
:DNA, not protein, is the material that stores
hereditary information |
|
|
Term
|
Definition
A nucleic acid monomer consisting of a five-carbon sugar
(deoxyribose), three phosphate groups, and one of four nitrogencontaining bases |
|
|
Term
DNA consists of four nucleotide building blocks
• Two pyrimidines: ______ and ______
• Two purines: ______ and ______ |
|
Definition
thymine; cytosine
adenine; guanine |
|
|
Term
Rosalind Franklin’s research in x-ray crystallography revealed
the dimensions and shape of the DNA molecule. What was it? |
|
Definition
|
|
Term
What was the final piece of information Watson and Crick
needed to build their model of DNA? |
|
Definition
| the dimensions & shape of DNA (alpha helix) |
|
|
Term
| DNA _____ ________ and ________ correct most replication errors |
|
Definition
| repair mechanisms; proofreading |
|
|
Term
| One template builds DNA ________; the other builds DNA ________, in segments. |
|
Definition
| continuously; discontinuously |
|
|
Term
| Breaks hydrogen bonds between DNA strands |
|
Definition
|
|
Term
| Joins free nucleotides into a new strand of DNA |
|
Definition
|
|
Term
| Joins DNA segments on discontinuous strand |
|
Definition
|
|
Term
DNA polymerases proofread DNA sequences during DNA
replication and repair damaged DNA |
|
Definition
|
|
Term
| When proofreading and repair mechanisms fail, an error becomes a ________– a permanent change in the DNA sequence |
|
Definition
|
|
Term
• Exact copies of a molecule, cell, or individual
• Occur in nature by asexual reproduction or embryo splitting
(identical twins) |
|
Definition
|
|
Term
| produces an exact copy (clone) of an individual |
|
Definition
| Reproductive cloning technologies |
|
|
Term
• Nuclear DNA of an adult is transferred to an enucleated egg
• Egg cytoplasm reprograms differentiated (adult) DNA to act like
undifferentiated (egg) DNA
• The hybrid cell develops into an embryo that is genetically
identical to the donor individual |
|
Definition
| Somatic cell nuclear transfer (SCNT) |
|
|
Term
________ ________ uses SCNT to produce human embryos
for research purposes |
|
Definition
|
|
Term
| ________ _________ was first to discover the molecular structure of DNA, but did not share in the Nobel prize which was given to Watson, Crick, and Wilkins |
|
Definition
|
|
Term
| _______ is toxic because it inactivates ribosomes, the organelles which assemble amino acids into proteins, critical to life processes |
|
Definition
|
|
Term
| Enzymes use the nucleotide sequence of a gene to synthesize a complementary strand of RNA |
|
Definition
|
|
Term
| Contains information transcribed from DNA |
|
Definition
|
|
Term
| Main component of ribosomes, where polypeptide chains are built |
|
Definition
|
|
Term
| Delivers amino acids to ribosomes |
|
Definition
|
|
Term
The information carried by mRNA is decoded into a sequence of
amino acids, resulting in a polypeptide chain that folds into a
protein |
|
Definition
|
|
Term
A multistep process including transcription and translation, by
which genetic information encoded by a gene is converted into a structural or functional part of a cell or body |
|
Definition
|
|
Term
| DNA ________ and ________ both synthesize new molecules by base-pairing |
|
Definition
| replication; transcription |
|
|
Term
| ___ ________ adds nucleotides to the transcript |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
• RNA polymerase and regulatory proteins attach to a promoter (a specific binding site in DNA close to the start of a gene)
• RNA polymerase moves over the gene in a 5' to 3' direction, unwinds the DNA helix, reads the base sequence, and joins free RNA nucleotides into a complementary strand of mRNA |
|
|
Term
| Many RNA polymerases can transcribe a gene at the same time |
|
Definition
|
|
Term
Base ________ in an mRNA are words in a protein-building
message |
|
Definition
|
|
Term
| In eukaryotes, RNA is modified before it leaves the _______ as a mature mRNA |
|
Definition
|
|
Term
| Nucleotide sequences that are removed from a new RNA |
|
Definition
|
|
Term
| Sequences that stay in the RNA |
|
Definition
|
|
Term
• Allows one gene to encode different proteins
• Some exons are removed from RNA and others are spliced together in various combinations |
|
Definition
|
|
Term
After splicing, transcripts are finished with a modified guanine
______ at the 5' end and a poly-A tail at the 3' end |
|
Definition
|
|
Term
|
Definition
|
|
Term
| mRNA carries protein-building information to ribosomes and tRNA for ________. |
|
Definition
|
|
Term
• A sequence of three mRNA nucleotides that codes for a specific amino acid
• The order of codons in mRNA determines the order of amino acids in a polypeptide chain |
|
Definition
|
|
Term
|
Definition
|
|
Term
• Consists of 64 mRNA codons (triplets)
• Some amino acids can be coded by more than one codon |
|
Definition
|
|
Term
Some codons signal the start or end of a gene
• ___ (methionine) is a start codon
• UAA, UAG, and UGA are stop codons |
|
Definition
|
|
Term
| tRNA has an _________ complementary to an mRNA codon, and a binding site for the amino acid specified by that codon |
|
Definition
|
|
Term
| ________, which link amino acids into polypeptide chains, consist of two subunits of rRNA and proteins |
|
Definition
|
|
Term
__________ converts genetic information carried by an mRNA
into a new polypeptide chain |
|
Definition
|
|
Term
| The order of the codons in the mRNA determines the order of the amino acids in the polypeptide chain |
|
Definition
|
|
Term
| Translation occurs in the ________ of cells |
|
Definition
|
|
Term
| What are the 3 stages of translation? |
|
Definition
1) Initiation
2) Elongation
3) Termination |
|
|
Term
• A small ribosomal subunit binds to mRNA
• The anticodon of initiator tRNA base-pairs with the start codon
(AUG) of mRNA
• A large ribosomal subunit joins the small ribosomal subunit |
|
Definition
|
|
Term
The ribosome assembles a polypeptide chain as it moves
along the mRNA
• Initiator tRNA carries methionine, the first amino acid of the
chain
• The ribosome joins each amino acid to the polypeptide chain
with a peptide bond |
|
Definition
|
|
Term
When the ribosome encounters a stop codon, polypeptide
synthesis ends
• Release factors bind to the ribosome
• Enzymes detach the mRNA and polypeptide chain from the ribosome |
|
Definition
|
|
Term
| Many ribosomes may simultaneously translate the same mRNA, forming ________. |
|
Definition
|
|
Term
Small-scale changes in the nucleotide sequence of a cell’s DNA
that alter the genetic code |
|
Definition
|
|
Term
May result in a premature stop codon or a different amino acid in a protein product
• Example:sickle-cell anemia |
|
Definition
|
|
Term
Can cause the reading frame of mRNA codons to shift, changing the genetic message
• Example: Huntington’s disease |
|
Definition
|
|
Term
| Segments of DNA that can insert themselves anywhere in a chromosomes |
|
Definition
|
|
Term
| Uncorrected errors in DNA replication |
|
Definition
|
|
Term
| Ionizing radiation, UV radiation, chemicals |
|
Definition
| Harmful environmental agents |
|
|
Term
| ________ _________ damages chromosomes, nonionizing (UV) radiation forms thymine dimers |
|
Definition
|
|
Term
• Mutations in somatic cells of sexually reproducing species are not inherited
• Mutations in a germ cell or gamete may be inherited, with evolutionary consequences |
|
Definition
|
|
Term
| Aristotle was one of first ________– people who observe life from a scientific perspective |
|
Definition
|
|
Term
| In the late 1800s, Alfred Wallace and others were pioneers in ________– the study of patterns in the observation of species |
|
Definition
|
|
Term
________ ________ study body plans and structures among groups of organisms
• Some organisms are outwardly similar, but different internally; others differ outwardly, but have similar internal structures
• Some organisms have vestigial parts with no apparent function |
|
Definition
| Comparative morphologists |
|
|
Term
| Georges Cuvier proposed that many species that once existed became extinct due to catastrophic geological events unlike those known today |
|
Definition
|
|
Term
| Jean-Baptiste Lamarck proposed that individuals changed in response to their environment, and passed those changes on to their descendents |
|
Definition
|
|
Term
• Lyell’s book, Principles of Geology, proposed that gradual, repetitive geological processes shaped the Earth over great spans of time
• Lyell’s insights shaped Charles Darwin’s thinking during his fiveyear voyage on the Beagle |
|
Definition
|
|
Term
| Darwin’s observations of species in different parts of the world helped him understand a driving force of evolution – ________ |
|
Definition
|
|
Term
|
Definition
Populations can produce more individuals than their environment
can support
• Some versions of a trait might enhance an individual’s ability to
survive and reproduce in its particular environment
• Example: Finches in the Galapagos Islands |
|
|
Term
| Differential survival and reproduction among individuals of a population that vary in details of shared, inherited traits |
|
Definition
|
|
Term
| Any trait that enhances an individual’s fitness (ability to survive and reproduce in a particular environment) |
|
Definition
|
|
Term
_______ ________ Wallace drew on his own observations of plant and animal
species and proposed that natural selection is a driving force of evolution |
|
Definition
|
|
Term
| Remains of bones, teeth, shells, seeds, spores, or other body parts |
|
Definition
|
|
Term
| Evidence of an organism’s activities (nests, trails, footprints, burrows, bore holes, eggshells, feces) |
|
Definition
|
|
Term
| Substantial enough to help reconstruct patterns and trends in the history of life, and establish some lines of descent |
|
Definition
|
|
Term
| Reveals the age of a material by determining its radioisotope and daughter element content |
|
Definition
|
|
Term
• A form of an element with an unstable nucleus
• Decays into atoms of another element
• Example: uranium 238 →lead 206 |
|
Definition
|
|
Term
The time it takes for half of a radioisotope’s atoms to decay into a
daughter element |
|
Definition
|
|
Term
|
Definition
|
|
Term
• The chronology of Earth’s history
• Measured by radiometric dating and fossils in similar sequences of sedimentary rock layers around the world |
|
Definition
|
|
Term
All continents were once part of a supercontinent – Pangea – that split and drifted apart
• Evidence: Magnetic rocks |
|
Definition
|
|
Term
• The mechanisms of continental drift
• Plate grow from ridges and sink into trenches |
|
Definition
|
|
Term
• Ancient supercontinent, older than Pangea
• Similar fossils and geologic formations in Africa, India, South
America and Australia |
|
Definition
|
|
Term
| Individuals of the same species in the same area |
|
Definition
|
|
Term
• All individuals of a species share certain traits
• Individuals of a population vary in the details of their shared traits |
|
Definition
|
|
Term
| All genes found in one population |
|
Definition
|
|
Term
• Different forms of the same gene
• Determine genotype and phenotype
• Dimorphism and polymorphism |
|
Definition
|
|
Term
Mutations are the source of new alleles that give rise to differences
in details of shared traits
• ______ mutations usually result in death
• ________ mutations have no effect on survival or reproduction
• ________ mutations convey an advantage |
|
Definition
-Lethal
-Neutral
-Beneficial |
|
|
Term
| Relative abundance of alleles of a given gene in a population |
|
Definition
|
|
Term
Natural populations are never in _______ ________
• A theoretical state which occurs when a population is not evolving |
|
Definition
|
|
Term
Four processes of ________ (small-scale changes in a population's allele frequencies) prevent genetic equilibrium
• Mutation
• Natural selection
• Genetic drift
• Gene flow |
|
Definition
|
|
Term
| Five conditions required for a stable gene pool: |
|
Definition
1) Mutations do not occur
2) Population is infinitely large
3) No gene flow
4) Random mating
5) All individuals survive and reproduce equally |
|
|
Term
The Hardy-Weinberg formula can be used to determine if a
population is in genetic equilibrium
p
2
(AA) + 2pq (Aa) +q
2
(aa) = 1.0
• The frequency of the dominant allele (A) plus the recessive allele (a)
equals 1.0
p + q = 1.0 |
|
Definition
|
|
Term
• The differential survival and reproduction among individuals of a
population that vary in details of their shared traits
• A driving force of evolution
• Occurs in recognizable patterns depending on the organisms and their
environment |
|
Definition
|
|
Term
• Changing environmental conditions can shift allele frequencies in a
consistent direction
• Forms of traits at one end of a range of phenotypic variation become more common |
|
Definition
|
|
Term
Natural selection that favors an intermediate phenotype and eliminates
extreme forms |
|
Definition
|
|
Term
Natural selection that favors extreme forms of a trait and eliminates
the intermediate forms |
|
Definition
|
|
Term
| With ______ ________, some version of a trait gives an individual an advantage over others in attracting mates |
|
Definition
|
|
Term
Distinct male and female phenotypes (______ _________) is one outcome of sexual selection
-can easily tell the difference between males & females |
|
Definition
|
|
Term
• A state in which natural selection maintains two or more alleles at
relatively high frequencies
• Occurs when environmental conditions favor heterozygotes
• Example: Sickle cell anemia and malaria
• HbA/HbS heterozygotes survive malaria more often than people who make only normal hemoglobin |
|
Definition
|
|
Term
• A random change in allele frequencies over time
• Can lead to a loss of genetic diversity, especially in small populations |
|
Definition
|
|
Term
________ has occurred when all individuals in a population are
homozygous for one allele |
|
Definition
|
|
Term
• A drastic reduction in population size brought about by severe pressure
• After a bottleneck, genetic drift is pronounced when a few individuals
rebuild a population
• Example: Northern elephant seals, cheetahs
-severe, environmental, catastrophic |
|
Definition
|
|
Term
Genetic drift is pronounced when a few individuals start a new
population |
|
Definition
|
|
Term
• Breeding or mating between close relatives who share a large number of
alleles
• Example: Old Order Amish in Lancaster County, Pennsylvania (Ellis-van
Creveld syndrome) |
|
Definition
|
|
Term
• Physical movement of alleles caused by individuals moving into and
away from populations
• Tends to counter the evolutionary effects of mutation, natural
selection, and genetic drift on a population
• Example: Movement of acorns by blue jays
-good thing = more diversity |
|
Definition
|
|
Term
• Evolutionary process by which new species form
• Reproductive isolating mechanisms are always part of the process |
|
Definition
|
|
Term
• The end of gene exchange between populations
• Beginning of speciation
-occurs when the gene flow stops |
|
Definition
|
|
Term
Reproductive isolating mechanisms prevent interbreeding among
species |
|
Definition
• Heritable aspects of body form, function, or behavior that arise as
populations diverge
• Prezygotic isolating mechanisms prevent pollination or mating
• Postzygotic isolating mechanisms result in weak or infertile hybrids |
|
|
Term
• Reduced hybrid viability (ligers, tigons)
• Extra or missing genes
• Reduced hybrid fertility (mules)
• Robust but sterile offspring
• Hybrid breakdown
• Lower fitness with successive generations |
|
Definition
|
|
Term
• A physical barrier arises and ends gene flow between populations
• Genetic divergence results in speciation
• Example: llamas, vicunas, and camels |
|
Definition
|
|
Term
new species form within a home range of an existing species, in the absence of a physical barrier
-does not happen very often
-occurs more frequently in plants, not animals |
|
Definition
|
|
Term
| A change in chromosome number (________) can cause instant speciation |
|
Definition
|
|
Term
populations in contact along a common
border evolve into distinct species
-2 species that live near/border eachother |
|
Definition
|
|
Term
• Large-scale patterns of evolutioary change
• Includes patterns of change such as one species giving rise to multiple
species, the origin of major groups, and major extinction events |
|
Definition
|
|
Term
Two species in close ecological contact act as agents of selection on
each other (_______)
• Predator and prey
• Host and parasite
• Pollinator and flower |
|
Definition
|
|
Term
A lineage exists for millions of years with little or no change (e.g.
coelacanth) |
|
Definition
|
|
Term
Some complex traits in modern species held different adaptive value in
ancestral lineages (e.g. feathers in birds and dinosaurs) |
|
Definition
| Exaptation (preadaptation) |
|
|
Term
A burst of speciation that occurs when a lineage encounters a new set of
niches |
|
Definition
|
|
Term
A structural or functional adaptation that allows individuals to exploit
their habitat in a new way |
|
Definition
|
|
Term
| The irrevocable loss of a species from Earth |
|
Definition
|
|
Term
• Extinctions of many lineages, followed by adaptive radiations
• Five catastrophic events in which the majority of species on Earth disappeared |
|
Definition
|
|
Term
-normally copied from left to right
-reversed DNa, not parallel
-this copies in segments from end to beginning |
|
Definition
|
|
Term
-Adenine & Thymine
-Deoxyribose
-Double strand |
|
Definition
|
|
Term
-Adedine and Uracil
-ribose
-single strand |
|
Definition
|
|
Term
| How do translation and transcription differ? |
|
Definition
Transcription- involves a promoter, occurs in the nucleus
Translation- begins with a start codon |
|
|
