Extra nuclear Inheritance And Maternal Effect

Question 1

Do cytoplasmic inheritance follow medilian inheritance

Answer 1

No

Question 2

Is cytoplasmic inheritance biparental or uniparent

Answer 2

Biparental - rare
Uniparental- mostly

Question 3

Which parents is usually involved in extranuclear uniparental transmission

Answer 3

Maternal

Question 4

Maternal inheritance vs maternal effect

Answer 4

Maternal inheritance - cytoplasm and extranuclear by mother

Maternal effect- nuclear genotype of mother determines phenotype of offspring even when genes transmitted by both sexes

Question 5

Example of cytoplasmic/extranuclear inheritance

Answer 5

Mirabilis jalapa- fouroclock plant

Seed from white branch gave white progeny no matter on pollen

If branch has both white and green, it can be white or green or both white and green

Reciprocal cross different

Question 6

Phenotype controlled by mitochondrial gene

Answer 6

1. Petite( small colony of yeast) mutants of baker’s yeast ( saccharomyces cerevisiae)

Petite if small- bc low respiration, low groeth rate

Petite × wild
Segregation (mutation in nuclear gene - follow mendel)
Vegetative- neutral or suppressive (mutation in mitochondrial gene)

Segregation × wild- both petite and wild
Neutral× wild- wild all
Supressive × wild- mostly petite

2. Cytoplasmic male sterility
   Plant can’t form functional pollen
   Had S sterility factor instead of F fertility factor
   Recessive trait
   Dominant allele of nuclear fertility restorer fene- Rf- NO CMS
3. Endosymbiont
   Paramecium release paramicin which toxic to other bacteria - but requires kappa particals

If mu partical present kills other cells by conjugation

Question 7

Example of maternal effect

Answer 7

Coiling direction of shell 🐚 in lymnaea peregra
Mother controls
Coiling - left handed (sinister)
Right handed (dextral)
Till F2 result same as mendel
F3 difference