INTRODUCTION TO CYTOGENETICS Flashcards
is the study of inheritance in all its manifestations, from the distribution of human traits in a family pedigree to the biochemistry of the genetic material in our chromosomes - deoxyribonucleic acid, or DNA.
GENETICS
is the field of genetics that involves the microscopic examination of chromosomes.
CYTOGENETICS
The most basic observation that a cytogeneticist can make is to examine the
chromosomal composition of a particular cell.
Structures within living cells that contain genetic material.
CHROMOSOME
physically located within the chromosomes. Biochemically, each chromosome contains a very long segment of DNA
GENES
Coined the term cell in his studies of cork. Hooke saw, in fact, empty cells observed at a magnification of about thirty power
ROBERT HOOKE BEFORE 1860
hooke’s discovery
Empty hexagonal cells that looks like a honeycomb
Discovered living organisms (protozoa an bacteria) in rainwater
ANTON VANN LEEUWENHOEK BEFORE 1860
Produced magnifications of several hundred power from single lenses
ANTON VANN LEEUWENHOEK BEFORE 1860
Both organisms are unicellular
Protozoa and Bacteria
Bacteria has no
nucleus, membrane bound organelles
Protozoa has
nucleus, membrane bound organelles
Example of protozoa
Ameoba
Example of bacteria
streptococcus pyogenes
- (discoverer of Brownian motion) discovered the nuclei of cells
BEFORE 1860 - ROBERT BROWN
contain organized nucleus and organelles which are enveloped by membrane- bound organelles
- CELL (Eukaryote)
- Described mitosis in nuclei
BEFORE 1860 - HUGO VON MOHL
a process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells.
- MITOSIS
- summed the concept of the cell theory with his latin aphorism omnis cellula e cellula: all cells come from preexisting cells.
BEFORE 1860 - RUDOLF VIRCHOW
- Publication of his work on Pea Plants.
- Includes the discovery of chromosomes and their behavior.
1860-1900 - GREGOR MENDEL
- first used the term chromosome
1860-1900 - WILHELM GOTTFRIED VON WALDEYER
- Stated that inheritance is based exclusively in the nucleus.
1860-1900 - AUGUST WEISMANN
- Described the fusion of sperm and egg to form the zygote
1860-1900 - OSCAR HERTWIG
1900 - Three biologist working independently rediscovered Mendel’s landmark work on the rules of inheritance, beginning the era of Modern genetics
- HUGO DE VRIES
- CARL CORRENS
- ERICH VON TSCHERMAK
- Hypothesized that the behavior of chromosomes during meiosis explained Mendel’s rules of inheritance, thus leading to the discovery that genes are located on chromosomes
1900-1944- WALTER SUTTON
- Created the first genetic map, using the fruit fly.
- He showed that genes existed in a linear order on chromosomes.
1900-1944 - ALFRED STURTEVANT
- Showed that genes can be mutated artificially by X rays
LEWIS STADLER and HERMAN JOSEPH MULLER
- Showed conclusively that deoxyribonucleic acid - DNA - was the genetic material
1944- PRESENT - OSWALD AVERY
- worked out the structure of DNA - double helix structure
JAMES WATSON and FRANCIS CRICK
- expert in X-ray imaging that caught a photograph of a DNA but could not piece together the exact DNA structure.
- Controversy regarding the male- dominated world of genetics.
- Died at the age of 36 due to cancer.
1944- PRESENT - ROSALIND FRANKLIN
