Purdue Biol 241 Exam 2

Inversion

chromosome segment inverted

Pericentric inversion

centromere is included in the inverted segment

Paracentric Inversion

centromere is NOT included in the inverted segment

Results of Pericentric Inversion

1 normal non-recombinant gamete

2 nonviable recombinant gametes

1 non-recombinant gamete w/ pericentric inversion

Results of Para centric Inversio

1 normal non-recombinant gamete

2 nonviable recombinant gametes

1 non-recombinant game w/ paracentric inversion

Dicentric chromosome

2 centromeres, gets pulled apart by spindle fibers

Acentric Chromosome

no centromere, get lost w/out centromere

Translocation

movement of a chromosomal segment to a new location in genome

Nonreciprocal translocation

segment moves w/out reciprocal change

Reciprocal translocation

exchange of segments between 2 non-homologous chromosomes, semisterility

Alternate (reciprocal translocation)

yield viable progeny

Adjacent (reciprocal translocation)

huge loss of genetic information, does not yield viable progeny

Robertsonian translocation

2 nonhomologous chromosomes break at ends and larger segments fuse and smaller segments fuse

Familial Down Syndrome

Mechanism: Robertsonian translocation

1.) 46 normal

2.) 46 with "Down"

3.) Not survive (loss of other 21 chromosome)

4.) 45 "normal" carrier

Chronic Myelogenous Leukemia

translocation of chromosome 22 and 9, produces BCR-ABL (always on), uncontrolled cell division

4 characteristics of genetic material

Replicate, store info, express info, allow variation by mutation

Chargaff's Rule

Amt of A = Amt of T, Amt of G = Amt of C

Avery (1944)

Transformation principle is DNA

Hershey Chase

Demonstrated DNA enters bacterial cell during bacteriophage infection and directs viral reproduction, Labeled DNA with (32P), Labeled Protein with (35S)

Nucleotide

Nitrogenous base, Pentose sugar, Phosphate group

Purine

A and G

Pyrimidines

C, T, and U

C-2' location

presence of OH determines deoxyribose or ribose

C-5' location

location of phosphate group

Nucleotides Linked

Phosphodiester bond between phosphate of C5 and OH of C3

Rosalind Franklin

X ray diffraction --> helix

Watson and Crick

Right handed double helix, antiparallel strands, bases stacked, connected by base pairing, 10 bps per turn

mRNA

template for protein synthesis

tRNA

carry amino acids for protein synthesis

rRNA

most abundant, components of ribosome for protein synthesis

Higher Melting point of a DNA molecule

1.) stand could be longer

2.) Higher concentration of G/C base pairing