Class Notes (811,431)
Canada (494,750)
Biology (2,164)
BIOL 355 (42)
Lecture 19

BIOL 355 Lecture 19: Lecture 19

3 Pages
Unlock Document

University of Waterloo
BIOL 355
Dr.Cheryl Duxbury

Lecture 19 Support for Gene Mutation Theory: 1) radiation exposure (animal systems) leads to increased mutations of DNA and decreased L.S (accelerates aging?) 2) in humans, increased radiation leads to increased cancers 3fold increase in leukemia for women given pelvic xradiation for nonmalignant gynecological problems survivors of Hiroshima and Nagasaki (atomic bomb) show increase leukemia but children dont 3) long lived mutant mice and animals under calorie restriction seem to have a lower mutation frequency, at least in some tissues 4) liver and heart cells in old mice have more DNA mutations (3fold) than liver and heart cells of young 5) liver cells from mice with short L.S (1 year) have more mutations than longer lived strains (3 years) 6) nonsmoking young adults have 6fold less mutations in DNA than 60 year olds 7) cancer: evidence of mutations. Increasing mutation levels, increasing mutation rates as animals age Evidence that mutations in DNA can lead to altered proteins and diseases such as cancer etc: changes in DNA (somatic or germ) can cause loss of function in proteins or abnormal functioning proteins Intrinsic sources such as ROS, spontaneous chemical reactions and Extrinsic sources such as chemicals and radiations leads to DNA damage (ex; strand breaks, depurination and deamination) DNA repair pathways (eg; BER, NER, NHEJ) influence DNA damage DNA damage can lead to mutations, cell cycle arrest, transcription impairment, gene expression dysregulation, apoptosis etc This leads to cell loss and cellular dysfunction Causes stem cell depletion and disruption of tissue homeostasis Results in organismal ageing
More Less

Related notes for BIOL 355

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.