Meiosis and Mendelian Ratios Flashcards
(101 cards)
Example #1 – Jojo
Short Hair L_ – LL or Ll
Not Striped – aa
Orange/Black – XoXb
Intense Color – D_ – DD or Dd
Has Plaibald Spotting – Ss
Pleibald spotting genotypes
SS = NO white – melanocytes CAN migrate
***s allele = can’t spread melanocytes
Ss (Heterozygous) – Less than 50% white BUT not no whiete (Has some white – mostly around feet
- Only have 1 allele for migration
What controls Coat Color in cats
Controlled by a gene on the X chromsome
Coat Color in cats
Only come in orange or black – reast are midifications
White = absence of color
***Get different colors in fancy cats = by selection –> picking rare mutants
Example cat #2 (Willow)
Hair length – short –> L_ –> LL or Ll
Has striping – A_ –> Aa or AA
Coat color – Black –> XbY or XbXb (is grey but that means that it is really a mutaed black = coat color is black)
Coat intesity – diluted –> dd
Pleibald spotting – has no white = ss
Example cat #3 (Gertrude)
Coat color – Black –> XbY or XbXb
Pleibald –> Ss
Black and orange in cats
Co-dominet – at the organismal level they are codominant – see BOTH colors
See both orange and black NOT mix of the two = co-dominant
Example cat #4 (Marisa)
WHITE cat – SS (all white –> Means no malanocyte movement)
- White = absence of pigment –> melanocyltes can’t move = no pgment
***Has a grey tail –> means not really white cat – she is REALLY a black cat with a large white spot
White cat coat
Absence of pigment –> SS because the melanocytes can’t move = have no pigment
Where is there usually dark places in cat
Can have dark head + the rest is white because the melanocytes start in the brain stem
What did dad look like?
Pleibald:
Kittens = have less than 50% white – have Ss + some mostly white = ss
- Mom = Ss
- Means dad = Ss or ss (needs to have one s to give to kittens)
Hair length:
Mom – Short hair
All cats = short hair
Dad = Short hair OR long hair –> bevause mom has short hair + all kittens have short hair MEANS that mom + Kittens = L_ ==> means the kittens can be L_ (already can get L from mom so dad can be anything)
Stripes:
Dad = can have stripes or NOT (Aa or aa) –> Because mom has striped
- Mom = A_
- Some kittens have stripes and some do not – kittens = have aa
- Means mom is Aa (need a a to give aa cats)
- Dad is Aa or aa (striped or not) BUT needs 1 a to give aa cats
Color:
Dad = needs to be XbY because have cats that are XoXb and mom is XoXo = dad need to have Xb to give cats
Dilute:
Mom = dilute – dd
Cats – some not dilute
Dad = NOT dilute – needs to have D to give not dilute cats – Makes him DD or Dd
- No kittens are dillute = none are dd = dad doesn’t HAVE to be Dd BUT he can be
Two less tahn 50% white cates
Answer: 25%
Work through – both cats are Ss (both less tahn 50% white) –> means that when do punent square have 25% ss –> 25% are solid white
Test Cross
Test a dominent individuals (A_) that you do not know if they are homozygous domineant or heterozygous and want to figure out their genotype –> CROSS them with a recessive individual and look at offspring
0% of cats will have long hair
50%
Galton
Statistician – described correlations and regressions towards the mean
- Firgured out finger prints ate unique to indivual -- this was right - Decribed weather patterns - Vocal to sat traits are blended -- "traits are blended through generations -- wrong" - Considered the father of Eugentioccs -- wrong about this ***Came up with idea of nature Vs. Nurture -- is it envirnment or genetocs
Eugentics
The idea that we can improve humanity by controlled breeding
Mendelian genetics (History)
Look at peas
1865 – mendle published explanation on plant hybrids
- People know that offspring look like theor parents –> was thought that it was belnding of traits
THEN have mendle –> mendle comes and says that blenidng is NOT true
Mendle = father of genetics
1900 – Mendle’s work was rediscivered – becayse Galton his work was ignored for 40 years BUT was then rediscovered
Idea of inheritance before mende
People knew that offspring look like their parents BUT thought it was blend of traits
Mendle BIG idea
Said that blending of traits is not true – said that traits are discrete and hide + reappear
- Not blend
- He said that there are versions of genes (alleles)
Mendle experimntes
Established true breeding lines – showed that F1 and F2 offspring had predicatibel phenotypes
F1 = all green
F2 = 3:1 ration of green:yellow
True breeding line
Means that green = only makes Green
Yellow - only makes yellow
BUT means that they are homozygous – So green is homozygous for green and yellow is homozygous for yellow
Crossing true breeding lines
True bree + True breed –> F1
F1 X F1 –> F2
***In F1 X F1 – get predicatble genotypes
What did mendles F1 show
F1 phenotypes show dominent vs recesisbve relationships
