unit 4 exam genetics
transcription
"script" one written form to another. -both DNA and RNA use nucleic acids
translation
"tanslates" one language to another. -we go from nucleic acids to amino acids
genetic code
-"nearly universal" -only 20 amino acids make up proteins, but DNA only has four kinds of of info A, T C, G and can't use them all at one time
watson and crick
-DNA STRUCTURE -discovered the DNA double helix
gene structure is based on what two nucleic acids?
-DNA and RNA
DNA replication in bacteria
-DNA is in loops, and the parent strand double helixes -when the replication fork meets, the replication will be complete
polymerase error
-DNA polymerase, RNA polymerase -when the polymerase recognizes an error, the mismatched base is transferred to the exonuclease active site and the base is excised (cut out)
DNA transcription
-DNA to RNA -a messenger RNA (mRNA is copied from DNA by unzipping a PORTION of the DNA helix that corresponds to a gene) -entervening sequenses (introns) are removed and remaining portions (eons) are ready to be translated
sickel cell anemia as incomplete dominance, which means for each of 3 genotypes there are 3 phenotypes
-Dominant (capital) and -Recessive (lower case) alleles for Normal and Anemia -the heterozygote would be Malaria-Resitant.
In cattle, when white cattled are mated with red cattle, all the offspring are roan colored. For another trait in cattle. horniess is dominant to horned. White hornless cows are crossed with red, horned bulls. What is the genotype of the F1 generation? If many F1 X F1 crosses are made and 160 offspring are produced, how many would be expected to be roan and horned?
-F1 generation= RrHh -2/16
hemizygous
-Having only a single copy of a gene instead of the customary two copies. -All the genes on the single X chromosome in the male are hemizygous
mature mRNA
-RNA transcript that has been spliced and processed and is ready for translation in the course of protein synthesis.
Reciprocal translocation
-Segments from two different chromosomes have been exchanged into incorrect places where it didn't belong -deadly to the zygote
synonymous codons
-Three different bases (called synonymous codons), for instance, can code for the same amino acid, proline: CCA, CCG and CCC. -Because of this oversupply of possible codons, some amino acids can allow more than one codon to designate them.
test crosses
-a cross of an individual with a dominant phenotype (but an unknown genotype (AA,or Aa) with a homozygous recessive (aa) -if the ressive phenotype appear to be in in almost half of the offspring, we can determine the unknown genotype as heterozygote
deletion
-a mutation in which a part of a chromosome or a sequence of DNA is lost during DNA replication. THE DOG dog RAN; the ran
genomics
-a study of the structural and functional aspects of the entire set of genes in a species
aneuploidy
-abnormal number of chromosomes -prophase 1 -leads to turner syndrome,klinefelders syndrome- mental retardation
RH negative
-absent
amino acids
-all organsims in the world have the same genetic code, excusing a few microbes
the hardy-weinberg law
-allelic frequencies and genotypic ratios remain constant in sexually reproducing populations as long as: -mutations do not occur, -there is no net movement of individuals in or out of the populations, -all offspring have equal chances of survival, - mating is random, -population large enough to not alter frequencies of alleles
RNA polymerase
-also known as DNA-dependent RNA polymerase, is an enzyme that produces primary transcript RNA. -In cells, RNAP is necessary for constructing RNA chains using DNA genes as templates, a process called transcription
alleles
-alternate forms of the same gene that could occupy the same locus -homologous chromosomes possess two representatives of each gene
branch (fork) diagrams
-alternatives to punnet squares where the multiplication rule is used to calculate the genotypic and phenotypic ratios
polymerase chain reaction
-amplifies a segment dna without using bacteria or host organism -DNA heated until the helix denatures, creating two separate DNA strands resulting in multiple copies of DNA -creates billions in short amount of time
reverse transcriptase
-an enzyme that reverses the transcription process and causes the information to flow backwards from RNA back to DNA. -this created complimentary DNA
comparative genomics
-analysis of gene sequences of different species
the most important factor about blood transfusions are the donors _________ and the recipients ________
-antegon -antibody
RH factor
-antigen found on the surface of red blood cells in some humans and other primates -bloodtype genetype allele produced
genes that are linked
-are most likely close to eachtother on the same chromosome
genes that that are unlinked
-are on different chromosomes so they are more likely to assort independently
individuals with blood type AB have
-as both A and B antigens on red cells -no antibody
determining gamete types
-assuming there are no mutations, alleles present in gametes are determined by the diploid genotypes of parents
codon
-basic unit of the genetic code; consists of three nucleotides that code for amino acids to build proteins
mendel used brushes to act like
-bees to test 7 traits; color
paternity cases
-blood type can determine paternity
an RH negative female can have a RH positive child, but what happens during birth?
-blood will mix and contain opposite antibodies to destroy red blood cells and can kill the baby
A certain hypothetical species called an EWOK has a gene that controls "fur" color — a dominant allele causes blue fur, and a recessive allele causes red fur color. Another gene controls "ear" length — a dominant allele causes long ears, and a recessive allele causes short ears. The two genes are linked. A cross is performed between an individual homozygous for both dominant traits and an individual homozygous recessive for both traits. C. What would be the possible phenotypes of the offspring in a test cross involving the offspring of question "A." (in other words, do a test cross on the offspring listed in question "A"). ASSUME NO CROSSING OVER
-blue fur, long ears -red fur, short ears
co-dominance
-both alleles are expressed fully -difficult to distinguish from incomplete dominance
Suppose you are a marriage counselor and a young woman comes to you for advice. She tells you that her brother has hemophilia, but both her parents are normal. She wishes to marry a man who had an uncle with hemophilia and wants to know the probability of the disease in possible children she may have. What would you tell her, and how would you explain your conclusions?
-both parents must be heterozygous -there is a 25% chance of having a son this is diseased
inheritance patterns
-classified based on whether they are autosomal or X-linked -and whether they have a dominant or recessive pattern of inheritance.
male x-linked genes
-color-blindness -hemophilia -muscular dystrophy
how does RNA differ from DNA?
-contains ribose - uracil replaces thymine -single stranded -shorter -less stable
gregor mendel
-developed the basic ideas of genetics long before chromosomes and genes were discovered -developed ideas by studying pea plant variations -his results and interpretations contrasted with a prevailing theme-blending
segregation of alternate factors
-developed using single trait crosses -he discovered that with certain traits, there were individuals which if only crossed with identical plants, they would almost always produce the same phenotype- true breeders
mendelian genetics
-devoloped by using statistics to analyze results of crosses involving distinguishing traits of garden peas
variations on theme
-different factors can account for the sex of a species -sometimes i's not determined by two distinct sex chromosomes, sometimes its environmental -n/2N, temp-induced
transcription of RNA synthesis
-doesnt need to unwind the entire DNA, only the certain helix needed for that gene
gene actions
-dominance, incomplete dominance, codominance, pleitropy, multiple alleles, monogenic vs. polygenic inheritance, epistasis, sex determination, linked vs unlinked genes, sex-linked traits, autsosmal linkage, sex inluenced traits, sex limited traits, environmental interactions
leading strand
-during DNA replication the side of the molecule that is SYNTHESIZED continuously with no interruption
nondisjunction of sex chromosomes
-during meiosis, chromosomes and/or homologous chromosomes may fail to separate, triggering alterations in phenotypic expressions of genotypes
DNA polymerase
-elongates the leading and lagging strands -enzymes that create DNA molecules by assembling nucleotides -enzymes are essential to DNA replication and usually work in pairs to create two identical DNA strands from one original DNA molecule.
how do cells know where they are and what they must do?
-epigenetics. the DNA sequence is modified to only express a certain gene/ phenotype. -DNA methylation and histone modification
estrogen will _______, and testosterone will _______
-feminize -masculine
hardy-weinberg law and natural populations
-few populations remain at equilibrium, so gene pools do occur in natural populations
environmental effects on phenotypes of flowers
-flower color can be effected by the pH of the soil
N/2N
-fly sex determinant factor is haploid or diploid cells -females produce eggs that can be fertilized or not and still can birth. -the ones that are haploid (not fertilized) become male
the earliest human fossils found
-found in africa, which were the tropics with an abundance of sun and UV radiation. -this led to the increase of melanin to protect against radiation and darker skin
structural genomics
-gene mapping and sequencing
RNA viruses
-genetic material stored as RNA so it can just directly translate into proteins
ligase
-glues the fragments of the okazaki together
retroviruses
-group of of RNA viruses possessing a special enzyme- (reverse transcriptasse) that allows the viral genome to go in the reverse direction of the information flow on the central dogma -this allows the viral RNA to be converted into DNA, altering the host cell genome -creating new and unneeded DNA
heterozygous genotype
-haploid gametes will be different for the given traits -Aa will produce either a or A; AaBb can produce AB, Ab, aB or ab
homozygous genotypes
-haploid gametes will be identical for the given traits -AA will only produce A, AAbb will only produce Ab
individuals with blood type A have
-has only the A antigen on red cells - (and B antibody in the plasma)
individuals with blood type B have
-has only the B antigen on red cells - (and A antibody in the plasma)
the self-not-self antibodies in our blood make transfusions a problem. they are least likely to happen if you
-have the same blood type with the same antigens
color blindness, hemophilia and muscle dystrophy are all
-hemizygous -if a male gets any of these, its from his mother
temperature induced
-hotter temperature leads to female turtles -cooler temperature leads to male turtles -middle sex temperature -sea turtles, crocs, reptiles
students later took the nuclei and discovered that
-if you put it in water, it creates nucleic acids
sex linkage
-in humans, genes are found on the X (color blindness) -the Y chromosome only determines gender
sex determination
-in humans, genes found on the X or Y chromosomes-SRY gene -not all animals have separate sex chromosomes
XO (Turner's Syndrome) and XXY (Kinefelter's Syndrome) emphasized. I wonder if XYY is possible? it is. what are the affects of the extra Y?
-increased growth velocity from early childhood -taller than average -Severe acne
DNA translations
-info from RNA is then used to synthesize a protein using ribosomes -rybosomes know the genetic code and will create the correct amino acids
the sequence of info from DNA is copied by RNA and then
-introns are removed and leave original exons
Pete has type B blood and is a diabetic. His wife, Jan, has type A blood and does not have diabetes. Pete and Jan have a child who has type 0 blood and is diabetic. What are the genotypes of Pete, Jan and their child? What is the probability that their next child will have type 0 blood and have diabetes?
-jan=AODd pete=BOdd Oscar= OOdd -1/8% of their offspring will be type O blood and have diabetes
zebras have black stripes, the white is a result of
-lack of pigmentation -calico cats are usually female, and never males because they can't have both orange and black colors
bacteria dNA is usually in what form and separates how?
-loops, and by binary fission because there is no nucleous
gene cloning
-making exact copies of genes -involves recombinant DNA and Polymerase chain reaction
simultaneous transcription
-many mRNA make copies of the DNA while the helix is open to make sufficient amount of protein for ribosomes
the law of independent assortment
-mendel continued his crossing experiments by looking at multiple traits simultaneously -he concluded that the alleles for one trait did not affect the inheritance of alleles for the other trait
human genome project
-monumental effort to determine the actual sequence of the entire set of chromosomes in humans -gene mapping
-multiple alleles
-more than two alleles are expressed for a gene are found within a population -blood type
autosome linkage
-multiple genes are found on non-sex chromosomes
polygenic inheritance
-multiple genes contribute to a single phenotype -skin color, at least 6 other genes are linked to skin color -no 3:1 ratios
mechanisms of evolutionary change
-mutations occur -individuals leave and enter populations -non random mating and natural selection occurs -small populations exist
incomplete dominance
-neither allele is expressed fully, "blended"
DNA replication
-new DNA is copied from existing DNA, conserving or using half of the original DNA while the other half is new -by pairing new nucleotides with the proper bases on each side of the separated DNA
individuals with blood type O have
-no antigens - (but both A and B antibody are in the plasma)
linkage groups leads to the conclusion that
-not all factors would sort independently -most traits are linked (hair, skin and eyes most likely on the same chromosome)
epistasis
-one gene alters and affects the others -pigement plays big role e.g. albino
pleiotropy
-one gene effects the several phenotypes -we originally were thought to have 100,000 genes, and now we are thought to have 10/20,000 genes because we realized that one gene is capable of multiple jobs
so, mendel concluded that there had to be physical entities
-passed on by each parent of a cross=genes -these factors came in pairs which become unpaired and recombined during fertilization -and that the two original true-breeders had these factors in alternate forms-called alleles -each parent had two, but only passed on one allele, thus their kids were hybrids genotypical, but only expressed the dominant phenotype
pedigree analysis
-phenotypes of all known family members are assembled and important to trace the sources of genetic disorders
pre-mRNA vs mature mRNA
-pre-mRNA is not spliced (has introns and exons) while -mRNA is spilced (has only exons).
polyploidy
-presence of more than two sets of chromosomes -intentionally going passed ploidy, triploid
RH positive
-present
translation and protein synthesis
-proteins are synthesized from mRNA by ribosomes (rRNA) which then read from a universal triplet code (codons)
gene mapping
-recombinant progeny can be used in some organisms to map gene loci; -molecular techniques are used for multiple species, including humans
restriction fragment length polymorphisms
-relies on the enzymes that protect bacteria from foreign DNA by cutting them at specific points called restriction sites at potentially susceptible sites while protecting their own DNA
what direction must synthesizing DNA go in?
-replication always occurs 5' to 3' -DNA polymerase moves "3' to 5' along the template DNA -new strand is made 5' to 3'.
reproductive cloning
-reproduces living cells with exactly the same DNA from donor cell. -not a true clone of donor -survival rates low
genetic engineering
-research involving gene transfer in non-human organisms -much more extensive -genetically modified plants and animals are becoming more common with potential to select desirable traits -saftey concerns are still high, but have been incorporated into a modern society
sex-influenced traits
-same genotype expressed differently in males vs females. -baldness in humans-it manifests quicker in males than females -men can get baldness from mother
sex limited traits
-same genotype expressed only in one sex, and suppressed in the other. -beard development and breast development in humans -also known as sex influenced
recombination mapping
-see how often traits recombine -this can be used in some organisms to to map gene loci
primary sequence
-sequence of amino acids that result in dehydration linkages to form peptide bonds
Mary has type A blood and normal vision. Mary's mother is type 0 and has normal vision while Mary's father is type AB and color-blind. Mary is married to Bob who has type AB blood ad is color-blind. What types of children could they expect with regard to these traits? (Include the sex of the children).
-sex is 50/50 -children can have either A, B, or AB blood and any variation of vision -two trait cross
beard development and breast development are a result of what kind of traits?
-sex-limited traits
so mendel decided to do ______________ to determine the causes for the previously stated observations
-single trait crosses
initiation of translation and protein synthesis
-small ribosomal subunit -shift 3 slots, 3=codon until the three stop codons
elongation
-stepwise addition of amino acids to the growing protein chain. -The order of amino acids is specified by the sequence of codons in the mRNA,
termination
-stop codon- messenger RNA -doesn't stop at a fragment
proteomics
-studies the functioning of the proteins coded by the genes
functional genomics
-studying how gene sequences operate, including proteomics (study of functional proteins coded by genes)
erythroblastosis
-the abnormal presence of erythroblasts in the blood. another term for hemolytic disease of the newborn.
chargaff's rule
-the amount of A is always equal to T, as well as G to C
probability and gametes
-the chances of a baby being a girl or a boy is 50/50, almost like a coin toss. -you won't alway get a 1/2 ratio, but you will come close the bigger the number of tries are
genome
-the complete genetic composition of a species -the set of genes for a species -phylogenetic traits based on genomes -the science of now -you can't always base evolution on phenotypes
nucleotides
-the components of nucleic acids - made of three subunits: phosphate, sugar (deoxyribose or ribose) and a nitrogenous base
the blending inheritance theory
-the concept that inherited traits mixed to create a composite characteristic in offspring -if you are taller, shorter, lighter, darker than your parents
homozygous
-the diploid condition in which both alleles of the genotype are identical (AA, aa)
heterozygous
-the diploid condition where both alleles of the genotype are different (Aa)
helicase
-the enzyme that that unwinds the double helix of DNA -a nonhistone protein
dominant alleles
-the expressed allele -written in capital letters
phenotypes
-the expression of a genotype- the observational inherited traits e.g. physical, behavioral, psychological, all based on the inherited genotype
recessive allele
-the not expressed allele, in lowercase letters
addition rule
-the occurrence of a mutually exclusive event equals the sum of their individual probabilities AA= 1/4 Aa= 1/2 aa=1/4; so the probability of the dominant phenotype is equal to AA(1/4) + Aa(1/2) =3/4
the central dogma
-the rules for molecular biology -once DNA structure was discovered, the function of the nucleic acids were understood
the primary structure of RNA is
-the sequence of the amino acids
environmental effects on phenotypes
-the siamese cat and himalayan rabbit are albino except on coldest part of body with a lot of melanin causing unusual black spots
what are the gene functions?
-to be preserved and transmitted -to control various biological functions through the production of proteins and RNA
gene therapy
-treating diseases and injuries using retroviruses that possess the enzyme -reverse transcriptase- that creates genetic information into DNA -normal info flow occurs from DNA
anticodon
-triplet sequence of nucleotides on tRNA that allow for the base pairing with mRNA during protein synthesis
transfer RNA
-trna -brings specific amino acid in the sequence dictated by the mRNA, which in turn was built based on the sequence of the nucleotides in the original gene portion of the DNA
bioinformatics
-uses computer/statistical applications to access large databases concerning DNA/gene/protein information
complimentary DNA is needed for the replication of retroviruses such as HIV.
-uses reverse transcriptase to transcribe their genomes back into DNA and integrate themselves into the host genome and replicate along with it
therapeutic cloning
-using reproductive cloning to create human embryos to produce stem cells -treatment for many diseases -growing ethical and political issue
blood groups
-we make new blood every 2/3 months. -we have about one gallon of blood in us at all times
transcription unit
-what is being transcribed -make hundreds of thousands of mRNA to take to the rybosomes
cytological mapping
-what molecular biologists are doing today - a type of chromosome map. On a cytological map, genes are positioned based on cytological findings, such as staining with dyes and labeling with probes, as well as chromosomal abnormalities and mutations
rough ER
-with ribosomes that read RNA
barr bodies
-woman are genetically compassionate, so only 45 chromosomes work -inactivated, condensed X chromosome; found in female mammals with two X chromosomes in somatic cells
the genotypic ratio for a dehybrid cross of F2
1 :1:1:1:2:2:2:2:4
what is the probability that a phenotypic recessive will appear in a F2 dihybrid cross?
1/16
X-linkage
10% genetic information is on the X-chromosome
human genome has how many genes?
10/20,000 -we have less than we thought we did
mendel looked at seven traits in the pea plants, this means that they have how many chromosomes?
14
In humans, blood types A and B are equally dominant (codominant). Both types are dominant to type O. A man with type AB blood marries a woman with type O blood. Give the genotypes and phenotypes of all possible offspring.
1⁄2 AO, 1⁄2 BO
males produce how many types of gametes and what do they do?
2, and they confirm the sex
A hypothetical recessive allele in humans causes the feet to grow backwards. The normal dominant allele causes the feet to grow forwards. Another gene controls foot length, and its alleles display incomplete dominance. When a person is heterozygous for foot length alleles, he or she will have normal-sized feet. When homozygous for either of the two foot length alleles, however, the person will be either big-footed or small-footed. A cross occurs between a backwards-pointing, large-footed male and a homozygous forward-pointing, normal-sized-footed female. B. Give all possible phenotypes of the offspring
2, forward-big forward-normal
how many chromosomes are in the sperm head?
23
the expected genotypic ratio of the f2 individuals in a monohybrid cross would be
2:1:1 Pp, Pp, PP, pp
gene mapping involved over
3 billion base pairs -several molecular techniques employed with automated computer assisted analysis -number probably doesn't exceed 40,000
A hypothetical recessive allele in humans causes the feet to grow backwards. The normal dominant allele causes the feet to grow forwards. Another gene controls foot length, and its alleles display incomplete dominance. When a person is heterozygous for foot length alleles, he or she will have normal-sized feet. When homozygous for either of the two foot length alleles, however, the person will be either big-footed or small-footed. A cross occurs between a backwards-pointing, large-footed male and a homozygous forward-pointing, normal-sized-footed female. C. In the original cross, if the male parent had backwards-pointing feet, but were of normal size, how many different phenotypes in the offspring would be possible?
3 different types forward-big forward-normal forward-small
what is the phenotypic ratio for F1 hybrids?
3:1
the expected phenotype ratio for f2 individuals in a monohybrid cross would be
3:1 thee purples, one white
what is the probability that a a phenotypic recessive trait would occur in a dihybrid cross?
4
what is the probability that a genotypic recessive will appear in a F2 dihybrid cross?
4 1:1:1:1:2:2:2:2:4
AA, and aa would produce
4 Aa, a genotypic hybrids
how many autosomes to humans have?
44
how many functional chromosomes do we have in the human cell?
45
what is the number used for the the genetic code usage?
4x4x4=64; 4^3
In certain cats, tail length is determined by a gene that demonstrates incomplete dominance. The allele that causes a long tail (T) is not completely dominant over the allele that causes no tail (t). If a cat is heterozygous for this trait (Tt), then the cat will have a short tail. What is the probability that the offspring will be manx cats (no tail) if a short - tailed cat is bred with a manx cat (no tail)?
50 % of the offspring will be manx cats.
In pea plants, yellow seed color is dominant to green seed color. If a heterozygous pea plant is crossed with a plant that is homozygous recessive for seed color, what is the probability that the offspring will have green seeds?
50 % of the offspring will have green seeds.
If a man with blood type A, one of whose parents had blood type O, marries a woman with blood type O, what percentage of their offspring would have blood type OO?
50 % of the offspring would have blood type O
how many genotypes total in a dihybrid cross of F2
9
There is a gene that affects pea pod color and has two alleles: G = yellow and g = green. There is another gene that affects pea pod shape and has two alleles: W = round and w = wrinkled. D. If the individuals of question "C" are crossed with each other. How many genotypes will be possible in the offspring?
9 genotypes. -remember the dihybrid cross for two traits of F2 will yield 9 gametes
the phenotypic ratio for a dihybrid cross of F2
9:3:3:1
There is a gene that affects pea pod color and has two alleles: G = yellow and g = green. There is another gene that affects pea pod shape and has two alleles: W = round and w = wrinkled. E. Give the phenotypic ratios of the offspring produced in question "D" (do not list the phenotypes again here).
9:3:3:1 -remember this is the PHENOTYPIC RATIO for F2 in a two trait cross
DNA replication, translation and transcription all occur in
S phase of interphase
If all of the offspring of a particular cross have the genotype Gg, what must the genotype of the parents be?
The genotypes of the parents must be GG and gg.
two trait cross
The p generation consisting of two true-breeding parents of different forms (phenotypes purple and white) for two traits were crossed to produce F1 individuals -color and height
stop codons, how many are there and what are they?
UAA< UAG< UGA three
what is the tRNA for AUG
UAC, the anti codon
the hybrids were then cross pollinated making a monohybrid cross which is
a cross involving two individuals with the same heterozygous genotype (Aa, Aa)
back cross
a cross of an F1 individual (Aa) with either of the two P generation individuals (AA or aa)
the discovery that DNA is the informational molecule housing genes started
a revolution in biology
In rabbits, black fur (B) is dominant to white fur (b). Perform the following crosses. For each cross, give the phenotype and genotype of all offspring. A. BBxbb B. BbxBb C. BBxBb
a) Bb -black fur b) BB, Bb,bb -black and white c)BB, Bb -black
inversion
A portion of the chromosome has broken off, turned upside down, and reattached, therefore the genetic material is inverted. the NAR GOD
duplication
A portion of the chromosome is duplicated, resulting in extra genetic material THE DOG dog RAN; the ran
the F1 generation genotypic hybrids for both traits were then crossed-the dihybrid cross- and produce
F2 generations
Incomplete dominance is seen in snapdragons. The allele that causes red flowers (F) is not completely dominant over the allele that causes white flowers (f). When a plant is heterozygous for the trait of flower color (Ff), pink flowers result. Cross two pink snapdragons, and provide the genotype and phenotype of all offspring.
FF = red ff = white Ff = pink
Red - green color blindness is a sex - linked recessive trait. Suppose a man with the disease marries a normal woman. Will any of their children have the disease?
None of the offspring will be colorblind. However, all of the female offspring will be carriers for colorblindness.
what genotypes create O blood
OO
Using the information given in #10, perform a cross between two plants that are each heterozygous for both traits. Give all possible genotypes and phenotypes of the offspring.
Phenotypic ratio - 9 yellow, smooth : 3 yellow, wrinkled : 3 purple, smooth : 1 purple, wrinkled Genotypic ratio - 1/16 DDTT : 2/16 DDTt : 2/16 DdTT : 1⁄4 DdTt : 1/16 DDtt : 2/16 Ddtt : 1/16 ddTT : 2/16 ddTt : 1/16 ddtt
proteins are determined by
RNA
the molecule of life for viruses
RNA
ribo "nucleic acid"
RNA -ribo=similar sugar that lacks oxygen -mostly used in protein synthesis -the molecule of inheritance in some viruses
ncRNA
RNA that can directly perform functions in cell without translation, like transfer RNA and ribosomal RNA which are used for the translation of messenger RNA into protein
1) A segment of DNA has one strand with the following sequence of bases: AGCGCATAGCAA The complimentary strand of DNA would be: a. UGCCGUAUCGUU b. TCGCGTATCGTT c. GAUAUGCGAUGG d. CTATACGCTACC e. AGCGCATAGCAA
b. TCGCGTATCGTT
A certain hypothetical species called an EWOK has a gene that controls "fur" color — a dominant allele causes blue fur, and a recessive allele causes red fur color. Another gene controls "ear" length — a dominant allele causes long ears, and a recessive allele causes short ears. The two genes are linked. A cross is performed between an individual homozygous for both dominant traits and an individual homozygous recessive for both traits. B. How many types of gametes can be produced by the offspring listed in questions "A."
b/c the two are linked, it produces FL and fl. two gametes
A hypothetical recessive allele in humans causes the feet to grow backwards. The normal dominant allele causes the feet to grow forwards. Another gene controls foot length, and its alleles display incomplete dominance. When a person is heterozygous for foot length alleles, he or she will have normal-sized feet. When homozygous for either of the two foot length alleles, however, the person will be either big-footed or small-footed. A cross occurs between a backwards-pointing, large-footed male and a homozygous forward-pointing, normal-sized-footed female. D. In the original cross, if the female parent had normal-sized feet but backwards-pointing, how many different phenotypes in the offspring would be possible?
bbLL, bbLl back-big back-normal
why do males have the most health afflictions?
because X has 10% of all genes
hense, traits did not _______ in these individuals
blend
A certain hypothetical species called an EWOK has a gene that controls "fur" color — a dominant allele causes blue fur, and a recessive allele causes red fur color. Another gene controls "ear" length — a dominant allele causes long ears, and a recessive allele causes short ears. The two genes are linked. A cross is performed between an individual homozygous for both dominant traits and an individual homozygous recessive for both traits. A. Give the phenotypes(s) of all possible offspring.
blue fur, long ears
A certain hypothetical species called an EWOK has a gene that controls "fur" color — a dominant allele causes blue fur, and a recessive allele causes red fur color. Another gene controls "ear" length — a dominant allele causes long ears, and a recessive allele causes short ears. The two genes are linked. A cross is performed between an individual homozygous for both dominant traits and an individual homozygous recessive for both traits. D. Do the same thing here as you did in question "C," but now give the possible phenotypes ASSUMING CROSSING HAS OCCURRED.
blue-long blue-short red-long red short
fetal karnenus
born without pheanase and can't process certain sugars that are in soft drinks
In cats, black fur and orange fur are determined by alleles on the X-chromosome with the heterozygous cat being a calico with patches of black and patches of orange fur. If a calico female is mated to a black male, what is the probability that a female kitten will be black? What is the probability a male kitten will be calico?
a)25 % probability of a female black cat b)0% probability a male kitten will be calico
A segment of DNA has one strand with the following sequence of bases:AGCGCATAGCAA The complimentary strand of RNA would be: a. UCGCGUAUCGUU b. TCGCGTATCGTT c. AGCGCAUAGCAA d. CTATACGCTACC e. AGCGCATAGCAA
a. UCGCGUAUCGUU
what are the four nitrogenous bases found in DNA?
adenine, guanine, cytosine, and thymine
think of the 5 end to 3 end as a
anti-parellel. -like the north and south of I95. they are parallel, but run in opposite directions
mutation
any random, permanent change in the DNA. -many are harmful, some have no affect, and some are even beneficial and will become adaptations that shape the course of evolution
in genetics, always
assume no mutations
2) The following sequence codes for which of the following sequences of amino acids - 5' - AUGUCUUUAUCCUUG - 3' a. met-arg-glu-arg-glu b. met-glu-arg-arg-glu c. met-ser-leu-ser-leu d. met-ser-ser-leu-ser e. met-leu-phe-arg-glu
c. met-ser-leu-ser-leu
probability rules
can be used to calculate genotypes and phenotypes, in place of using punnet squares -are especially useful in multiple trait crosses
chromosomal mutations
change in chromosome # or structure
point mutation
change in one nucleotide base pair -has a better chance at not making an impact
autosomes
chromosomes that don't determine sex
the chiasmata needs to be at the exact point or else
chromosonal mutations will occur, along with errors to the organism -deletion, duplication, inversion, reciprocal translocation
mendel discovered that factors are passed on from parents and
come in pairs
human genomics is extremely
concise but complex
most phenotypes are
extremely complex to understand
monohybrid cross: once mendel realized that the f1 individuals were genotypic "hybrids", he predicted the recessive trait that "disappeared" would reappear if
f1 hybrids were crossed to produce F2 offspring -and if they had heterozygous gametes
the monohybrid cross produced
f2 indivduals
pedigree
figure showing phenotypes of all known relatives
proposita
first diagnosed female
propositus
first diagnosed male
proband
first person a particular gene condition was diagnosed
RFLP is used often in
forensic, criminal and paternity cases
the fragments created by these restriction points will be the same if
from the same individual, and different from anyone else-like a fingerprint
tests on linked genes were run mostly on
fruit flies by intentional crosses
every cell in our body contains all 23 pairs of chromosomes except
gametes
paired gene alleles are segregated and independently assorted during meiosis, producing
gametes that combine to form offspring
factors/genes separated during
gametogenesis
mendel is to gene function, as Meischer is to
gene structure
hereditary information
genes are found along the linear sequence of nucleotides in the DNA molecule
gene pool
genetic composition of a population of individuals -(all the alleles for all genes in a population) -populations evolve just as species do
when crossing over occurs, the more likely it is to
get all for genotypic combinations
gene therapy raises many ethical questions but
has tremendous potential -limited success and legal restrictions
male chromosomes are
hemizygous: XY
all genetic "carriers" are
heterozygous
however their children would be AaBb, meaning they would be considered
heterozygous
mendel also found that some individuals with similar appearance when crossed, would not have offspring of the same kind, these have what kind of genotype?
heterozygous
what kind of genotype is a hybrid?
heterozygous genotype
the exact position of restriction points are
highly individual, reproducible and measurable
true breeders of opposite forms, AABB-aabb, would be considered
homozygous
F1 generations would have what kind of genotype?
hybrids, because they are now no longer homozygous
introns is short for
interveining sequence and needs to be removed
this "junk" DNA is known as
introns
what does RNA process?
introns and exons
the more complex an animal is the
less likely it is to regenerate
genes on the same chromosome are
linked
locus
location of a specific gene on homologous pair of chromosomes
homologous pairs have the same
loci, thus genes -when the two chromosomes are present=diploid -when only half of the pair is present (gametes)= haploid
meischer started to
look at the DNA -he isolated the pus nuclei and found the nuclein
most animals produce sperm via
meiosis
where does nondisjuntions occur?
meiosis 1, 2. extra/lacking chromosomes
independent assortment
mendel concluded that statistically, these results occurred b/c the allele of one trait did not affect the inheritance of allele for the other trait
what is the start codon
methianine
male bees create sperm via
mitosis
Three children are left orphans when their parents are killed in an automobile crash. The physician finds that the one boy of the three is color-blind, one girl is color-blind, and the second girl has normal color vision. Show the genotype and phenotype of each parent.
mom= XCxc -normal vision female father=XcY -color blind male
In some cases, distinguishing between incomplete dominance and codominance is difficult. For example, although a pink flower appears to be blended from white and red alleles, on a microscopic level it is possible that both red and white spots are present.
on a microscopic level it is possible that both red and white spots are present.
complete dominance
one allele dominates another allele
one codon=
one amino acid
monogenic inheritance
one gene contributes to a single phenotype
organismal reproduction
one of the most important requisites of all life
a parental generation would initiate these experimental crosses by using two true breeding pea plants for
opposite phenotypes-purple vs white
DNA copies the entire strand, where as RNA just
copies a certain portion
recombinant DNA includes restriction enzymes that
create DNA fragments with the gene of interest, and DNA
A hypothetical recessive allele in humans causes the feet to grow backwards. The normal dominant allele causes the feet to grow forwards. Another gene controls foot length, and its alleles display incomplete dominance. When a person is heterozygous for foot length alleles, he or she will have normal-sized feet. When homozygous for either of the two foot length alleles, however, the person will be either big-footed or small-footed. A cross occurs between a backwards-pointing, large-footed male and a homozygous forward-pointing, normal-sized-footed female. E. In the cross with the female above ("D"), will any offspring have forward-pointing feet?
nope
a heterozygous female for a sex-linked trait should be considered to have a "________" phenotype.
normal
molecular biotechnology
now a pervasive component in modern societies
only one side of the DNA will be transcribed and
nucleotides with the proper bases will be sequenced to build pre-mRNA
DNA is found in the
nucleus
DNA synthesis and replication
occurs in the S phase of interphase
messenger RNA
serve as temporary copies of the information found in DNA
codons
sets of three nucleic acid, with 64 different possibilities -aaa, ccc, ggg, uuu
monohybrid
single trait, Aa x Aa
with 20 amino acids, the genetic code leads to
some repeats= a good thing why? because there are synonymous codons that create the same amino acid
allosomes
special chromosomes that determine sex in animals
loci
specific positions on DNA
RNA processing is also called
splicing
human pedigree
studying inheritance patterns of humans is complex both biologically and ethically. thus, much of what we know is based on looking at family history and trees
punnet squares
summarize results in a single-trait cross similar to those done by mendel on pea plants and there organisms
semiconservative DNA replication
temple of making DNA
genes
the functional unit of inheritance and the basis for most traits -located at a loci to be preserved and transmitted
genotype
the genetic composition of an organism -the specific alleys present in the organism
mendels 2nd law
the law of independent assortment
the farther apart genes are
the more likely recombinations would be
multiplication rule
the probability of independent events occurring simultaneously is equal to the products of their individual probabilities AABbcc= (1/4)(1/2)(1/4)= 1/32
genetics
the study traits and their inheritance
If you are talking about two traits, always assume that
their are 4 chromosomes unless linked
9/16 of the F2 would express both dominant traits; 3/16 expressed 1 dominant trait and 1 recessive; 3/16 expressed the opposite recessive and 1/16 expressed both recessive
this is the phenotypic ratio for a dehybrid cross of F2
there, he found that 3/4s of the individuals expressed the dominant trait, while 1/4 expressed the trait that wasn't represented in F1 (white)
this latter trait is known as the recessive
t/f, males can get breast cancer
true
true or false? the majority of genes are pleiotropy
true -one gene affects several phenotypes
progeny tests
true breeders creating hybrid
t/f we know more about the genetics of many organisms than that of humans
true. -b/c there are fewer ethical issues and shorter generation times for non-human organisms
what are the advantages of being diploid?
two chances to make something work, less mutations
dihybrid
two traits, AaBb x AaBb
3:1 and 9:3:3:1 phenotypic ratios are
uncommon in nature
genes on different chromosomes are
unlinked and assort independently
we all have the same genome t/f
we have 46 chromosomes, 23 pairs
which sperm is faster?
y sperm, more likely to be involved in fertilization=twice as many male embryos conceived -most miscarriages are males
does a gamete posses the same genome as the individual who produces it?
yes
can enviromental factors affect phenotypes?
yes, the genotype and environment interact to form a phenotype
evolution involves changes in gene pools overtime. in order to understand the changes in gene pools
you must have an understanding of non evolving populations
-what genotypes create A blood
AA, AO
what genotypes create AB blood
AB
the start codon
AUG= produces the start codon
what genotypes create B blood
BB, BO
A hypothetical recessive allele in humans causes the feet to grow backwards. The normal dominant allele causes the feet to grow forwards. Another gene controls foot length, and its alleles display incomplete dominance. When a person is heterozygous for foot length alleles, he or she will have normal-sized feet. When homozygous for either of the two foot length alleles, however, the person will be either big-footed or small-footed. A cross occurs between a backwards-pointing, large-footed male and a homozygous forward-pointing, normal-sized-footed female .A. The female can produce how many gametes as far as these traits are concerned?
BL, Bl
you can only reference a punnet square if
Colum and rows produce a unique gametes,
RNA is determined by
DNA
mRNA seeks info from
DNA
the molecule of inheritance for all cellular life forms
DNA
what serves a template for the RNA
DNA
deoxyribo nucleic acid
DNA -molecule of inheritance in all cellular forms of life
mendels 1st law
segregation of alternate factors
There is a gene that affects pea pod color and has two alleles: G = yellow and g = green. There is another gene that affects pea pod shape and has two alleles: W = round and w = wrinkled. A. Mendel's original crosses (P generation) would have consisted of what two genotypes? (Hint: this is progeny testing)
GGWW, ggww or ggWW, GGww
There is a gene that affects pea pod color and has two alleles: G = yellow and g = green. There is another gene that affects pea pod shape and has two alleles: W = round and w = wrinkled. B. List all of the possible gametes produced by these first or original parent plants.
GW, gw, OR Gw, gW
Hemophilia is a disease caused by a gene found on the X chromosome. Therefore, it is referred to as a sex - linked disease. The recessive allele causes the disease. A normal man marries a woman that is heterozygous for the trait. Give the genotypes and phenotypes of all possible offspring.
Genotypes: 1⁄4 XH XH , 1⁄4 XH Xh, 1⁄4 XHY, 1⁄4 XhY Phenotypes: 1⁄4 normal females, 1⁄4 carrier females, 1⁄4 normal males, 1⁄4 hemophiliac males
In corn, seeds can be either yellow (D) or purple (d). Seed texture can either be smooth (T) or wrinkled (t). Suppose a plant that is homozygous dominant for color and heterozygous for texture is crossed with a plant that is purple and wrinkled. Give all possible phenotypes and genotypes of the offspring.
Genotypic ratio - 1 DdTt : 1 Ddtt yellow, smooth seeds,yellow, wrinkled seeds
There is a gene that affects pea pod color and has two alleles: G = yellow and g = green. There is another gene that affects pea pod shape and has two alleles: W = round and w = wrinkled. C. If the gametes of question "B" are joined, what will the genotype(s) be in the offspring?
GgWw
dehydration linkage
Monomers are connected together by the removal of H2O from BETWEEN them
Diabetes, a recessive trait, occurs in 10% of a certain population. What is the proper letter used as a symbol for the gene concerned? If a normal female and a normal male in this population have a child who is diabetic, what is the probability that their next child will be a diabetic?
d= diabetes female= Dd male=Dd 25% chance that they will have a child with diabetes
what do you call 2 amino?
dipeptide
okazaki fragments
during DNA replication, the side of the molecule that must be synthesized in fragments
the genome of the organism is represented in
each cell
-true breeders
either all purple or all white -they have a homozygous genotype
where does DNA copying occur?
outside the nucleus? -rybosomes make protein outside the nucleus
algebraic equivalent of the hardy weinberg law
p2 + 2pq+ q2 = 1
DNA fragments are then fused together with DNA from a bacterium called
plasmid
genes control biological processes through the
production of proteins and RNA
and DNA determines
protein
newly recombinant DNA is placed into bacteria and the bacteria produce
protein for which the cloned gene coded. -and large quantities of the gene and thus the protein are produced as the bacterial cell reproduces
the offspring only showed one of the traits which was ______. this was considered
purple, the dominant trait
ribosomal RNA=
rRNA -physically move along an mRNA molecule -catalyze the assembly of amino acids into protein chains. -They also bind tRNAs and various accessory molecules necessary for protein synthesis.
what two kinds of genetic mapping are there?
recombination mapping, and cytological mapping
tripeptide =
release