Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Cytoplasmic Inheritance

No description

Jas Dulai

on 19 March 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Cytoplasmic Inheritance

Cytoplasmic Inheritance What is Cytoplasmic Inheritance? Mitochondria and chloroplasts have their own genomes encoding small # of genes Pattern of Inheritance Most nuclear genes in diploid eukaryotes display Mendelian inheritance patterns
-Homologous chromosomes segregate during gamete production
-Offspring get 1 copy of each gene from each parent

Non-Mendelian Inheritance Not associated with meiosis and mitosis; organelles in cytoplasm not nucleus
Mitochondria and chloroplasts don’t segregate into gametes Extra-nuclear inheritance

It is the transmission of genes that occur outside nucleus, located in cytoplasmic organelles Three General Types of Cytoplasmic Inheritance Uniparental


Vegetative Segregation

Chloroplasts have been found to exhibit various modes of inheritance within the same species Uniparental Inheritance •Only 1 parent contributes DNA from organelle to offspring

•Most common type of cytoplasmic inheritance

•Example: Maternal Inheritance-transmission of mother’s mitochondria at fertilization via the egg

•Can’t predict this inheritance Biparental Inheritance Both parents contribute DNA from organelles to offspring

When 2 haploid cells from both parents fuse, they both give their mitochondria to diploid offspring

Can be seen in some types of yeast; not very common Vegetative Segregation Replicative Segregation
Random replication and partitioning of cytoplasmic organelles
Occurs in chloroplasts and mitochondria during mitotic cell divisions resulting in daughter cells with random samples of parent cell’s organelles.
Example: Asexually replicating yeast cells Homoplasmy vs Heteroplasmy Demo Activity LHON (Leber’s hereditary optic neuropathy) Mitochondrial inheritance disease with incomplete penetrance
Reasons for incomplete penetrance include:
-Effect of heteroplasmy
-Effect of genetic interactions with nuclear genes
-Effect of environmental factors with the mitochondrial gene Figure 1: Pedigree showing maternal inheritance with incomplete penetrance of LHON. Summary •Cytoplasmic inheritance transmits genes carried on organelle chromosomes
•Cells or organisms in which all genomic copies of an organelle gene have identical sequence are said to be homoplasmic for that gene, whereas, cell or organisms possessing multiple alleles for an organelle gene are heteroplasmic
•Inheritance of organelle genomes can be uniparental, biparental or vegetative. Homoplasmic cell-all copies (alleles) of a cytoplasmic organelle gene are the same
Heteroplasmic cell-a mixture of alleles of an organellar gene
Full transcript