Coding Life: Patterns of Inheritence Flashcards

Question

mendel and the law of independent assortment

Answer 1

True breeding strain of yellow wrinkled and green round crossed Get 9 yellow round, 3 green round, 3 yellow wrinkled and 1 green wrinkled 9:3:3:1 Gametes can be AB, Ab, aB or ab These genes are acting independent to each other so we can predict this ratio

Answer 2

Diploid cell is Aa and Bb Can get AB x2 and ab x2 or Ab x2 and aB x2 Completely random, two traits controlled by two genes that behave independently

Answer 3

Two breeds of chooks One is white because of an inhibitor that inhibits pigment One does not produce pigment In F2 generation, most are white but some are brown (lack inhibitor and have one dominant allele for colour) Inhibitor masks what is happening at colour locus so the ratio is 13:3 instead Not independent assortment

Answer 4

``` Horizontal line is mating Vertical line is progeny Squares are males Circles are females Diamond is when gender is unknown Identical twins have a big triangle joining them Fraternal twins have a small triangle Double line horizontally means mating between relatives The shaded symbol is affected by a trait ```

Answer 5

Affected individuals in each generation Vertical transmission from generation to generation About half of progeny are affected Equally likely to be males or females Penetrance: has the trait or does not have it Reduced penetrance: has the alleles but does not show it and looks like the trait skips a generation Expressivity: can have it to different degrees

Answer 6

Skips generations Equally likely to be males or females Often results from incest (consanguineous)

Answer 7

``` Small circular DNA in mitochondria Mutations in it can lead to disease Passed from mother to children Affected female passes it onto all her children An affected male will not pass it on All that are affected show the trait ```

Answer 8

Only share a few genes (at the tips which helps them to pair up) 50% males and 50% females

Answer 9

Red eyes female crossed with white eyes male F1 all have red eyes F2 have females with red eyes and males are 1:1 red or white X-linked recessive (females are heterozygous or homozygous without the trait) and males have it and are affected or do not have it

Answer 10

Usually affected individuals are male (one X) Heterozygous female may be unaffected but can pass it onto sons Sisters of affected males might have affected sons If a male is affected, sons are not affected (receive the Y) x linked dominant have different frequencies (more 50/50)

Answer 11

Two genes are located on the same chromosome and do not segregate independently - always red eyes and weird wings (parental combinations) But crossing over and recombination can mean that white eyes have weird wings (recombinant)

Answer 12

Cross over in prophase 1 and physical exchange of chromosome occurs Frequency is a measure of the physical distance between the two genes - can form genetic maps The further apart, the more likely recombination will occur between them. More likely to stay together if closer Non-recombinant are parental

Answer 13

multiple genes and environmental factors influence traits Height in humans Milk production in cows Skin colour Get a distribution curve Twin studies can look at how much genes are involved

Answer 14

Genetic linage and x linkage are exceptions to Mendel

Answer 15

Males are hemizygous (only a single copy of a chromosome, resulting in expression of the phenotype)

Answer 16

the person seeking genetic counselling

Answer 17

most abundant trait in a population (anything else is a mutation)

Answer 18

``` Copper builds up in the body Autosomal recessive Pre-natal screening Discuss treatment options Better disease surveillance - keep in touch with family to see what’s going on ```

Answer 19

Humans share 99.9% of their DNA 0.01% is large and can be used to build a unique profile like a fingerprint Used in forensics, paternity testing etc.

Answer 20

Short Tandem Repeats (STR) is used - consider them like alleles. All are equal but have different numbers of repeat 15/11 heterozygous or 15/15 homozygous No dominant or recessive Inherited from parents Can see what repeat come from each parent We will use STR to determine what baby belongs to what mother We will have 3 loci Less repeats = shorter PCR

Answer 21

Amplifies specific sections of DNA Increases exponentially Requires primers that bind to the chromosome at specific regions Bind outside the STR region Replication forks form and move towards each other Use temperature (94) to seperate strands, decrease to 64 for annealing and raise again for extension

Answer 22

DNA is negative when dissolved in water Oxygens lose a hydrogen and become negative Apply electric current and it moves away from the cathode (negative electrode) to positive electrode Smaller molecules will move further Longer ones have more resistance Wear gloves to prevent cancer (chemical binds to DNA permanently) Use pipette to load ladder (DNA strands) Load into well Use a new tip for each sample Thicker, brighter band (doublet) means they are homozygous for the same locus 50% DNA will be shared with the mother so we can work out whose baby is whose

Answer 23

Turning genes off and on Looking at prokaryotic gene structure Organised in operons (grouped genes that have same function) No introns Promoter - located upstream of genes. RNA polymerase binds here to transcribe Operator may inhibit RNA polymerase by putting proteins on the operator araC binds to operator and bends DNA so that the RNA polymerase is blocked Insulin is produced by using recombinant plasmids - needs to be controlled otherwise cells die

Answer 24

Using reporter genes (gfp) behind op and prom and this allows us to determine the amount of therapeutic generated Strength of promoter determined by the amount of GFP produced Tight = how stringent it is = specificity of regulation Only want it expressed when it is turned on Be given different op and prom mutants and work out when best GFP production occurs GFP will glow green under UV light In silico analysis we will look at sequences of DNA Compare each mutant to the wild type Lack of asterixes mean there is disparity and might be the cause of change in results