Cyto Flashcards
Hybrid science which attempts to correlate cellular events, especially those of the chromosomes, with genetic phenomena
Cytogenetics
Cytogenetics is the combination of?
Cytology and Genetics
Steps of the cell cycle
G1 -> S -> G2 -> M
G1 - Prepare to Grow 10H
S - Replication 9H
G2 - Prepares to divide 4H
M - Mitosis/Meiosis 1H
Which steps of the cell cycle is considered Interphase?
G1, S, G2
Step in the M-phase that consists of:
- Condensation of chromosomes
- Each chromosome is already doubled
Prophase (1/2)
Step in the M-phase that consists of:
- Mitotic Spindle Formation (Microtubules become spindles)
- Centromeres located at polar ends of cell
Metaphase
Point of attachment for centromeres and spindles
Kinetochore
Step in the M-phase that consists of:
- Pulling apart due to progressive shortening of spindles
- Separation of chromosomes
Anaphase (1/2)
Once chromosomes are separated, they are now considered ______________. (2 words)
Sister Chromatids
Step in the M-phase that consists of:
- Formation of Nuclear Envelope
Telophase (hehe mb)
Differentiate Meiosis I and Meiosis II
Meiosis I - Reductional Division (Ploidy decreases)
Meiosis II - Equational Division (Ploidy stays the same)
Generalized Parts of Chromosome (3)
P arm - shorter arm
Q arm - longer arm
Centromere
consists of a p and q arm
Chromatid
DNA-protein structures found at each end of a chromosome
Protect the genome from degradation
Telomere
Black bands
Gene-poor
Not actively transcribing
In interphase they are condensed and tightly packed
Made up of repeated satellite DNA
Can silence euchromatic gene expression
30-nm fiber
Heterochromatin
Also called the Primary (1°ry) constriction
Region where kinetochore proteins are located
Binds two sister chromatids together
Made up of repeated α-satellite DNA
Centromere
White band
Actively transcribing
More open/loosely packed
Allow recruitment of RNA polymerase complexes and gene regulatory proteins to initiate transcription
Made up of nucleosomes
11-nm Fiber
Euchromatin
Any narrowing or constricted point in the chromosome other than the centromere
Site of Nucleolar Organizer Region (NOR)
18S and 28S ribosomal genes that synthesize rRNA for ribosomes
Forms a satellite at the distal end of the chromosome
Stalk/ 2°ry constriction
A part of the chromosome that is separated from the rest via a secondary constriction
Used as markers in research
Satellite
Types of Chromosomes based on Number and what does it mean
Monad - only one sister chromatid
Dyad - two sister chromatids
Tetrad
- Four sister chromatids
- Two homologs during synapsis pairing
Types of chromosomes based on the number of centromeres and define.
Univalent - Only one centromere; monad or dyad
Bivalent - two centromeres; only tetrad
Types based on locations of centromeres
Metacentric
Submetacentric
Acrocentric
Telocentric
Type of chromosome where both arms are equal in length
Metacentric
Type of chromosome where one arm is slightly longer than the other
Submetacentric