Question | Answer |
What does Hardy-Weinberg Equilibrium demonstrate? | The persistence of allele frequencies over time |
What did Dobzhansky do? | Linked mechanism (ns) w |
What happened in 1952? | The discovery of the significance and structure of DNA |
When did the ability to sequence DNA come about? | 1960s |
Allele | a different form of a gene |
Genotype | the specific allele combinations in an individual |
Phenotype | The observed traits of an individual affected by both genotype and environment |
Does natural selection operate on genotype or phenotype? | Phenotype |
What are 3 ways to describe genotypes? | Homozygous, heterozygous, hemizygous |
Homozygous (aka ?) | aka “true breeding”- Both alleles are the same |
Heterozygous | A genotype that has 2 different alleles |
Hemizygous | A haploid genotype- there is only 1 allele present |
What are 4 ways to describe phenotype? | dominant, recessive, incomplete dominance, codominance |
Dominant | A given allele is expressed |
Recessive | A given allele is masked |
Incomplete dominance | phenotype is intermediate (~pink) |
Codominance | Both alleles are expressed (intermediate- ~red & white) |
How do we get blood type? | A transferase creates specific glycoproteins that act as antigens and are placed on the cell's surface; These antigens give you your blood types (A antigens = type A, no antigens = type O) |
What are the 4 blood types? | A (A glycoprotein), B (B glycoprotein), AB (both A & B glycoproteins), O (no recognizable glycoprotein) |
How many alleles are there for blood type? | 3 (A, B, & O) |
At what gene locus is blood type? | Transferase |
How many genotypes are there for blood type? | 6 (A, AO, B, BO, AB, OO) |
How many phenotypes are there for blood type? | 4 (A, AB, B, O) |
How are genotypes translated into phenotypes? | Replication, transcription, & translation |
Replication | The process by which DNA is copied |
Transcription | The process by which information in DNA is transferred into messenger RNA (mRNA); mRNA is created in the nucleus & must be transported to the cytoplasm where ribosomes await |
Translation | The process by which information in mRNA is utilized to create proteins on ribosomes |
Why are there different genotypes? | Mutation |
Mutation | An inherited change in the DNA |
Does order of the nucleotides matter and why? | Yes- specific nucleotide sequences make up specific amino acids which help to create a protein |
What are the two major types of mutations? | Micromutations and macromutations |
What are the 4 types of micromutations? | Synonymous, missense, nonsense, frameshift |
Synonymous mutation | A change in a nucleotide base doesn't cause a change in an amino acid [sequence] |
Missense mutation | A change in a nucleotide base causes a change in amino acid [sequence] |
Frameshift mutation | A change in amino acid sequence occurs following the insertion of one nucleotide base |
Nonsense mutation | When a nucleotide mutation causes a stop codon to be translated and there is premature termination of protein synthesis |
Which of the four micromutations have the least impact on phenotype? | Synonymous (no change in amino acid sequence) |
Which of the four micromutation shave the greatest impact on phenotype? | Frameshift & nonsense |
What are the four types of macromutations? | Deletions, duplications, Inversions, & Reciprocal Translocations |
Deletion | ABCDEFG → ABEFG |
Duplication | AB\CDEFG + ABCD\EFG → AB\EFG + ABCDCDEFG |
Inversion | ABCDEFG → ABEDCFG |
Reciprocal translocation | AB\CDEFG + HIJKL\MNOP → ABMNOP + HIJKLCDEFG |
What are 3 types of posttranslational processing? | Proteolysis, glycosylation, & phosphorylation |
Proteolysis | In creating a protein the mRNA is spliced |
Glycolysation | In creating a protein the mRNA has sugar added to it |
Phosphorylation | In creating a protein the mRNA has phosphate added to it |
What happens after posttranslational processing? | Proteins are assembled into functional molecules (like hemoglobin, a tetramer) |