Chromosomes And Cellular Reproduction Flashcards
What is a prokaryote? (3 items)
Unicellular with no compartmentalized cell structure.
DNA is circular and not highly packed.
Made up of eubacteria and archaebacteria.
How do prokaryotes replicate? (3 items)
Simple division: separation of replicated circular chromosome
Single origin of replication
High rate of replication
What is a eukaryote? (3)
Both unicellular and multicellular with compartmentalized cell structure.
DNA resides in the nucleus.
DNA is wrapped around histones to form tightly packed chromosomes.
Number of human chromosomes (1)
23 pairs = 46 chromosomes.
Chromosome structure (3)
Centromere - attachment point for spindle microtubules
Telomeres - tip of a linear chromosome
Origins of replication - where DNA synthesis begins
Chromatid (1)
One half of a paired chromosome (can also be called a chromosome)
Interphase (1)
Cell growth
Stages of interphase (3)
G1, S, G2
G1 (1)
Cell growth
G0 (3)
Non-dividing phase
Occurs when errors are present
Often leads to apoptosis
G1/S checkpoint (2)
DNA error checking point before entering S phase
Cancer blows through this checkpoint
S Phase (1)
DNA synthesis phase
G2 (1)
Mitosis preparation
G2/M checkpoint (1)
Last checkpoint before mitosis
M phase (1)
Mitosis and cytokinesis
Genetic consequences of the cell cycle (3)
Produces two cells that are genetically identical to each other
New cells contain a full complement of chromosomes
Each new cell contains approximately half (but not necessarily identical) the cytoplasm and organelle content of the original parental cell