Mutations Flashcards
What is a mutation?
A change in the DNA sequence
What do mutations result from?
DNA replication errors made during cell division
Exposure to ionizing radiation
Exposure to chemicals
infection by viruses
What is a Germ line mutation?
A mutation that occurs in the egg or sperm, affect all cells in the body and can be passed on to offspring
What is a somatic mutation?
occur in a body cell and is not passed on to offspring
Why are there more errors in RNA?
RNA polymerase does not proof read like DNA polymerase
Why do errors in transcription and translation matter less than errors in genome?
The cell will be making multiple copies of RNA, unlikely to make same mistake in exactly the same place
RNAs are quickly degraded so bad copies will be quickly removed,
Not inherited or permanent
What are mitochondria?
Energy producers
Where do mitochondrial diseases usually affect?
Heart
Brain
Muscles
What problems do people with mitochondrial disease usually suffer from?
muscle weakness, problem with movement, diabetes, kidney failure, heart disease, dementia, hearing loss, vision abnormalities
What happens with mitochondrial somatic mutations?
Can not repair themselves so build up over time- raging
What must happen for someone to spontaneously get an autosomal recessive disorder?
Mutation of the same gene on both chromosomes at the same time
What mutations lead to a frameshift?
Insertions and deletions
How can errors at mitosis produce chromosomal mutations?
if chromosomes do not pair correctly at the metaphase plate may cause two copies of the chromosome in one cell and not
What does PGC mean?
Primordial Germ cells
What are the stages of Oogenesis?
PCG Oogonia Some enter prophase- primary oocytes Primordial Follicle- primary oocyte surrounded by flattened epithelial cells secondary Oocyte and polar body ovulation Egg and polar body
800,000 at birth,
due to apoptosis 40,000 at pubery
500 ovulated
