Introduction Flashcards
Major parts of cells
Cell membrane
Cytoplasm
Nucleus
Membrane bound structures
Involved in the different metabolic activities of the cell
Cytoplasmic organelles
Small, electrons opaque particles of RNA and numerous proteins.
Ribosomes
Inclusion bodies
Secretory granules
Fat droplets
Water droplets
Pigments
Structures that form the framework of the cell
Cytoskeleton
Fine filaments coursing throughout the cytoplasm
Commonly occur as a thin sheet of filaments near the plasmalema
Microfilaments
Smooth muscle filaments
Tonofilaments
Striated muscle filaments
Myofilaments
Nerve cell
Neurofilaments
Usually found at the center of the cell
Nucleus
Composition of nucleus
Nuclear membrane
Chromatin materials
Nucleolus/li
Nucleopplasm
Cellular reproduction thru mitosis
Somatic cells
Cellular reproduction of somatic cells
Meiosis
Two daughter cells are produced, each with a chromosomal karyotype identical to that of the mother cell
Mitosis
Chromosome condense to form a compact structure and become visible
Chromosomes attached to the nuclear membrane via their telomeres
Prophase 1-1. Leptotene
Pairing of homologous chromosomes- chromosomal synapsis
Formation of a complex structure - synaptonemal complex - bivalent or tetrad
Prophase 1-2 Zygotene
Crossing over of nonsister chromatids of homologous chromosomes occurs at the recombination nodules
Chromosomes remain linked at the sites o crossing over
Prophase 1 - 3 pachytene
Dissolution of the synaptonemal complex and separation of the homologous chromosomes of the bivalents or tetrad except at the sites of crossing over
Prophase 1-4 diplotene
The X shaped structures formed during the separation are known as ———
Chiasmata
Marked by the termination of chiasmata and assembly of meiotic spindle to separate the homologous chromosomes
Prophase 1-5 diakinesis
The bivalents/ tetrads align at the equatorial plate and microtubules from the opposite poles attach to the pairs homologous chromosomes.
Metaphase 1
Homologous chromosomes separate while keeping the sister chromatids associated at their centromeres
Anaphase 1
Nuclear membrane reappears and is followed by cytokinesis to give rise to a dyad of cells
Telophase 1
Creates the haploid gametes that fuse together during the process of sexual reproduction
Meiosis
Study of cells
Cytology
Study of genetic materials
Genetics
The science that converges cytology and genetics
Cytogenetics
Concerned with the study of the structure and function of the cell, especially the chromosomes
Cytogenetics
A clinical laboratory scientist who carries out diagnostic testing, including culturing, harvesting, staining, photomicroscopy and chromosome analysis.
Cytogenetic technologist
Gave the first account of mitosis
1873
Franz Anton Schneider
Discovered fertilization in both plants and animals
1875
Oscar Hertwig
Showed that nuclear division involves a longitudinal splitting of the chromosomes
1879
Walther Flemming
Coined the term mitosis
1882
Walther Flemming
Coined the term chromosomes
1888
Heinrich Wilhelm Waldeyer
Described the sex chromosome
1902
Clarence E. Chung
Advanced the chromosome theory of heredity
1902
Walter S. Sutton
Introduced the terms: genetics, homozygote, heterozygote F1 and F2
1902
William Bateson
Coined the words, gene, genotype and phenotype
1909
Wilhelm johannsen
Suggested that exchanges between non-sister chromatids produce chiasmata
1909
Frans Alfons Jansses
Discovered different types of chromosomal abnormalities and aberrations
1917-23
Calvin B. Bridges
Noble prize for his development of the “Gene Theory”
1933
Thomas Hunt Morgan
Quantity of DNA for each haploid set of chromosomes is constant in the different cells of an organisms
1948
Andre Boivin, Roger Vendrely, Collete Vendrely
Demonstrated that the numbers of adenine, thymine, guanine and cytosine groups in DNA are always equal
1950
Erwin Chargaft
Proposed the DNA model
1953
James Dewey Watson
Francis Harry Compton Crick
Cracked mRNA code
1961
Marshall W. Nirenberg
J. Heinrich Matthaei
Showed that the genetic language is made up of three letter words
1961
Francis H.C. Crick & colleagues
Nobel prize for DNA structure
1962
James D. Watson
F. H. C. Crick
Maurice Hugh Frederick Wilkins
Worked out the complete genetic code
1968
Marshall W. Nirenberg
Har Gobind Khorana
Nobel prize for deciphering genetic code
1968
Marshall W. Nirenberg
Har G. Khorana
Robert William H. Holley
Bodies of tightly bound DNA and proteins that reside inside the cells of organisms.
Chromosomes
These bodies help keep genetic information safe and compact, making replication easy when it’s time for cells to divide.
Chromosome
Site of gene location
Chromosome
The complete set of chromosomes derived from both parents
Genome
46 chromosomes
Diploid
23 chromosomes
Haploid
Composition of chromosome
Long arm “q”
Short arm “p”
Centromere
A small body at the construction in a chromosome where it is attached to spindle fibers
Centromeres
A polar body which connect two strands of the chromosome
Centromere
Types of chromosomes
Metacentric
Submeracentric
Acrocentric
Telocentric
Divides the chromosomes into two arms of equal length
Metacentric chromosome
Centromere is very close to but not located at the end of one strand
Acrocentric
The centromere is intermediate in position between that of the metacentric and acrocentric chromosomes
Sub-metacentric/ sub median centric chromosome
Centromere is found at the very distal part or at the tip of the chromosomes
Telocentric
Not normally found in humans
Telocentric
Determines the karyotype of normal human chromosomes
Done through karyotyping
Groupings
Output of karyotyping
Idiogram
Technique for preparation of chromosomes, known as culture techniques for blood or tissue
Karyotyping
The process of matching pairs of chromosomes in accordance with standard basis of classification
Karyotyping
a diagrammatic representation of a karyotype of an individual
Idiogram
Involves the use of fluorescent probes-pieces of DNA that bind to corresponding DNA chromosomes
Fluorescent In Situ Hybridization
Pyramidine base
Guanine Cytosine
Purine Base
Adenosine
Thymine
Probe tagged with fluorophores
Probe with target antibodies: biotin ID/ streptavidin
Fish :probe
Probes that hybridize along an entire chromosome are used to count the number of a certain chromosome, show translocations, or identify extrachromosomal fragments of chromatin
Whole- chromosomes painting probe
A mixture of smaller probes can be created that is specific to a particular region (locus) of DNA; these mixtures are used to detect deletion mutation
Special Locus-specific probe mixtures
Often used to count chromosomes, by binding to the centromeric region of chromosomes, which are unique enough to identify each chromosomes (except 13, 14, 21, 22)
Fish probe: special
Fish : dye
Primary colors
Secondary colors
ROY G BIV
Created by mixing the correct ratio of two sets of differently colored probes for the same chromosome
M-fish
Double vision fish
Designed so that the secondary color will be present or absent in cases of interest
D- fish
Break apart fish
Absence of secondary colors
Used to investigate translocation where only one of the breakpoints is known or constant
BA Fish
Spectral karyotyping
This technique is used to identify structural chromosome aberrations in cancer cells and other disease conditions when Giemsa banding or other techniques are not accurate enough
Sky technique
A molecular technique used to simultaneously visualize all the pairs of chromosomes in an organism in different colors
Sky technique
A technique used to quantify the DNA copy number on a genomic scale
Digital karyotyping
Also known as virtual karyotyping w
Digital karyotyping
Uses digital cytogenetic analyzer
Digital karyotyping
