LS1 Midterm 1
Terms
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copy deck
- Pseudogenes
- duplicate copies of genes that have undergone one or more mutations that eliminate their ability to be expressed
- When are substitution rates in nucleotide positions the highest?
- When the positions don't change the amino acid being expressed
- If a molecule is essential of cell functioning, does it evolve fast or slow?
- slow
- Gene family
- a group of homologous genes with related functions, often arrayed in a tandem along a chromosome
- orthologs
- genes found in different organisms that arose from a single gene in their common ancestor
- paralogs
- genes that are related through gene duplication events in a single lineage
- What was Frederick Griffith's 1920's experiment?
- tested virulent and non-virulent types of pneumonia and found out that they shared genetic information
- What were the Hershey Chase experiments?
- The Hershey Chase experiments labeled proteins and DNA differently and discovered that DNA was the genetic material
- The amount of purines always equal the amount of
- pyrimidines
- Purine A =
- pyrimidine T
- Purine G =
- pyrimidine C
- What are the 4 nitrogenous bases?
- The 4 nitrogenous bases are Adenine, Cytosine, Guanine, and Thymine
- a DNA is made up of:
- a molecule of sugar deoxyribose, a phosphate group, and a nitrogen-containing base
- What is the shape of a DNA molecule?
- Double Helix
- What are the 4 key features of DNA?
-
1) it is a double-stranded helix
2) It has a uniform diameter
3) it is anti-parallel
4) it is right-handed - Adenine pairs with Thymine by forming ____ hydrogen bonds
- 2
- Guanine pairs with Cytosine by forming ____ hydrogen bonds
- 3
- Semiconservative Replication
- produce molecules with both old and new DNA, each new molecule will have one old strand and one new one
- Replication complex
- The close association of several proteins operating in the replication of DNA
- Origin of replication
- the part of the DNA where the replication complex binds
- Replication Fork
- A point at which a DNA molecule is replicating. The fork forms by the unwinding of the parent molecule.
- DNA helicase
- unwinds DNA
- single-strand binding proteins
- bind to the unwound strands strands to keep them from re associating into a double helix
- Primer
- a short, single strand of RNA , complementary to the DNA template strand
- Primase
- creates primer
- Telomere
- repetitive sequences at the end of chromosomes
- Telomerase
- catalyzes the addition of any lost telomeric sequences
- What are the three types of repair mechanisms? Describe them.
-
DNA proofreading - an incorrect base is taken out and polymerase adds a new base
Mismatch repair - proteins remove mismatched protein and bases around it and polymerase corrects the problem.
Excision repair - proteins remove damaged base and bases around it and polymerase replaces it - Instead of Thymine, RNA contains ___________
- Uracil
- The origin of genetic variation is __________
- Mutation
- what is a promoter?
- A portion of DNA where the RNA polymerase binds
- pyrophosphate
- used for energy in the RNA transcription process
- Frequency
- The relative proportions of all alleles in the population
- What are the 5 necessary conditions for the Hardy-Weinberg theorem?
-
1)Mating is random
2)Population size is very large
3)there is no migration between populations
4)there is no mutation
5)Natural selection doesn't affect the alleles under consideration - Individuals don't evolve, ___________ do
- populations