Concept 9.1
What is one of the observations that pointed to the possibility that DNA is the genetic material?
- is present in the cell nucleus and in condensed chromosomes
-doubles during S phase of the cell cycle
-it is twice as abundant in diploid cells as in the haploid cells of a given organism
List the base pairs with their appropriate complementary nucleotide. (what pairs with what in base pairing)
Adenine pairs with Thymine
Cytosine pairs with Guanine
What are mutations?
changes in the nucleotide sequence of DNA that are passed on from one cell organism to another
DNA was first isolated in 1868 by the young Swiss researcher-physician named?
Friedrich Miescher
What is a primer?
a short single strand of RNA that is the necessary starting material for the synthesis of a new DNA strand, which is synthesized from the 3' end of the primer
What is the difference between point mutations and silent mutations?
Point mutations are alterations in single base pairs of DNA. Silent mutations occur in genes or non transcribed regions and do not affect the amino acid sequence of proteins.
Describe antiparallel as it relates to DNA
pertaining to molecular orientation in which a molecule or parts of a molecule have opposing directions
A single replication fork opens up in one direction. True or False?
True
What causes spontaneous mutations to occur versus what causes induced mutations to occur?
Spontaneous mutations occur because of instabilities in DNA or chromosomes and induced mutations occur when a mutagen damages DNA
What did Crick and Watson build to establish the general structure of DNA?
They built the first accurate model of DNA
What are the two major repair mechanisms for DNA?
1) proofreading
2) mismatch repair
Define somatic mutations and gremlin mutations
- somatic mutations: occur in the body cells of an individual and are passed on to daughter cells during mitosis
- gremlin mutations: (mutations in the cells that give rise to gametes) can be passed on to sexually produced offspring
What are the four important functions of the genetic material?
1) Storage of genetic information
2) Precise replication during the cell division cycle
3) Susceptibility to mutations
4) Expression of the coded information as phenotypes
DNA replication takes place in what two general steps?
1) The DNA double helix is unwound to separate the two template strands and make them available for new base pairing.
2) As newly added nucleotides form complementary base pairs with template DNA, they are covalently linked together by phosphodiester bonds.
What are the four types of chromosomal mutations?
1) deletions
2) duplications
3) inversions
4) translocations