Extranuclear inheritance, imprinting, & maternal effect Flashcards
Genes that follow the mendelian pattern follow what four rules?
- The genes obey mendel’s law of segregation
- Except in the case of rare mutation the genes are passed unattered from generation to generation
- The expression of the genes in the offspring directly influence
- For crosses involving two or more genes & th genes obey mendel’s law of independent assortment
Nuclear genes
Genes located in the nucleus
Extranuclear inheritance (Cytoplasmic inheritance)
Type of non-mendelian inheritance pattern that involves genes that are not located in the cell nucleus & where the inheritance of organellar genetic material (from the chloroplast & mitochondria)
Chloroplast contains ___________ chromosomes with many genes
Circular chromosomes
Nucleoid
Where the genetic material of the chloroplast is loacted at
Extranuclear inheritance produces _______________ results in reciprocal crosses
Non-mendelian
Inheritance of ______________ genetic material doesn’t display mendelian pattern because chloroplast & mitchondria are not sorted during meiosis (& don’t segregate into gamtes as nuclear chromosomes do)
Extranuclear
Reciprocal Cross
The phenotype of the maternal (mom) & paternal (dad) parents are reversed
Maternal inheritance
The maternal phenotype determines the offspring phenotype
chloroplast usually inherits traits from the __________ parent
Maternal parent (because the egg provides the genetic material)
To predict the phenotype of extranuclear offsprings can’t use a punett square instead have to look for what two things?
- Need to know if the offspring inherits the gene from the mom, dad or both
- Need to know if heteroplasmy (carries both normal & mutant genes) is present & who transmit the extranuclear gene
(ex. If a gene is inherited from the mother & the mother has white leaves than can predict that the offspring will have white leaves)
The primary role of the mitochondria is to provide cell with _______
ATP
The transmission of the mitochondria usually follows the _______________
Maternal inheritance (the female determines the offsprings phenotype)
Many human diseases are caused by ________________
Mitochondrial mutations
Disease can occur in what two ways?
- Mitochondrial mutations that cause disease may be transmitted from mother to offspring
- Mitochondrial mutation may occur in somatic cells & accumulate as a person ages
Endosymbosis
A symbiotic relationship in which the symbiont actually lives inside the host
Endosymbiosis theory
Indicates that the acient origins of chloroplast was initated when a cyanobacterium took up residence within a primordial eukaryotic cell
Epigenetic inheritance
A pattern in which a modification occurs to a nuclear gene or chromosome that atters gene expression
_______________ results of DNA & chromosomal modification that occur during oogenesis, spermatogensis, or early stages of embroyogensis
Epigentic inheritance
Genomic impriting (impriting)
A type of epigenetic inheritance wherre a modification occurs to a nuclear gene that atters gene expression
The _____________ of an imprinted gene depends on the sex of the parent from which the gene was inherited
Expression
_______________ is a segment of DNA that is marked & that mark is retained & recognized throughout the life of the organism inheriting the marked DNA (depends if htey get the mark from mom or dad)
Genomic imprinting
To predict the phenotype of offsrping from a imprinted gene can’t use a punett square instead need to know what?
- Need to know if the offspring expresses the allele that is inherited from the mother or the father
- Need to know which allele was inherited from the mother & which allele was inherited from the father
The imprint is established during ______________
Gametogenesis
