16.1 The cell cycle Flashcards
Rudolph Virchow
concluded that new cells arise only form the division of other cells
cell cycle +two stages (3)
- growth stage
- division stage
life cycle of the cell
DNA (3)
- where genetic information of a cell is contained,
- a molecule of nucleic acid that governs processes of heredity in the cells of organisms
- found in each chromosome of a cell
chromosome (2)
- a length of DNA and its associated proteins
- found in the nucleus
Histones
highly organized arrangements of proteins found in eukaryotic cell nuclei that package and order the DNA into structural units to make it fit
Chromatin (3)+ what happens in cellular division?
- Long interlined strands of genetic material
- most of a cell’s life its genetic matter is in this state
As the genetic material is reorganized during the process of cellular division, the threads of chromatin condense and become visible under a light microscope as distinct chromosomes.
Centromere
- the constricted pinched in region in the condensed chromosome
How many chromosomes do human somatic cells have? (The details of the separations) (3)
46 chromosomes
- 22 pairs of homologous chromosomes=autosomes
- twos ex chromosomes
Homologous chromosomes: (3)
- carry the same genes
- not identical to each other
- they carry different forms or alleles of the same gene
Diploid (2)
A cell that contains pairs of homologous chromosomes
- 2n=46
Haploid with example (3)
- a cell that contains umpaired chromosomes
- Human gametes or repro cells
- n=23
Polypoid+ex: (2)
- have sets of more than two homologous chromosomes
- 4n/3n/8n
similarity of homologous chromosomes (3)
- length
- centromere location
- banding pattern
karyotype
the particular set of chromosomes that an individual possess
Interphase+ ends when (5)
- growth phase
- most of the life of the cell is spent in this stage
- cell carries out its regular metabolic functions and prepares for its next division.
- three phases in interphase: G1, G2, S
- ends when the cell gains the process of nuclear division: mitosis
G1
Rapid growth and metabolic activity
S phase (3)
DNA synthesis and replication
- cell DNA is copied
- DNA in the chromatin replicates to create a second identical set
G2 (4)
Cell prepares for division
- second growth period
- allows cell to rebuild its reserves of energy to prepare for division
- manufactures proteins and other molecules to make structures for division
2 main processes in cell division:
- Mitosis
- cytokinesis
Mitosis
the division of the genetic material and the contents of the nucleus into two complete and separate sets
Cytokinesis
The division of the cytoplasm and the organelles into two separate cells
