Unit 1: The Cell Cycle Flashcards
DNA is packaged into multiple chromosomes as ?
Chromatin
Where are chromatins stored?
The nuclear envelope
The two main phases of the cell cycle are?
M phase and interphase
Within interphase there are three sub phases called?
G1 phase, S phase and G2 phase
What happens in the G1 phase?
Protein synthesis occurs and new organelles are formed
What happens in the Synthesis phase?
Replication of nuclear DNA
What happens in the G2 phase?
Duplication of centrosome
By the end of interphase the parent cell has usually ____ in size?
Doubled
What two processes occur during the M phase?
-Mitosis and Cytokinesis
What generally takes place in mitosis?
The separation and segregation of replicated chromosomes and the formation of daughter nuclei.
What generally takes place in cytokinesis?
division of cytoplasm into two separate daughter cells
Mitosis is split into four phases which are:
Prophase, Metaphase, Anaphase and Telophase
In prophase, what happens to the chromosomes?
replicated chromosomes condense and appear as identical chromatids which are held together by protein glue
In prophase, what happens to the centrosomes?
They move apart and microtubules radiate from them to form spindle fibres
In prophase, what cellular structure is broken down?
The nuclear envelope
In metaphase, what do the spindle fibres attach to?
The sister chromatid
In metaphase, what happens to the chromosomes?
They align along the equator, this position is called the metaphase plate
In anaphase, what happens to the protein ‘glue’ that was holding the sister chromatids together?
It is degraded
In anaphase, due to the protein glue being degraded what happens to the sister chromatids?
They separate and are now known as daughter chromosomes
In anaphase, the spindle fibres attached to each of the daughter chromosomes shorten and?
Pull the daughter chromosomes to opposite poles of the cell
In telophase, What happens to the daughter chromosomes when they arrive at the cell poles?
They decondense or unravel
In telophase, what is formed around each group of daughter chromosomes?
A new nuclear envelope
Cytokinesis overlaps with which two mitosis stages?
anaphase and telophase
Cytokinesis is accompanied by the insertion of what to compensate for the increased surface area of the daughter cells?
Plasma membrane
Cytokinesis is achieved by the action of what?
A contractile ring of structural and regulatory proteins
The location of the contractile ring in cytokinesis is specified by what?
The spindle fibres
Cytokinesis in plant cells: The cytoplasm is sectioned off by the formation of a new what?
Cell wall (the cell plate)
Cytokinesis in plant cells: The formation of the cell plate is guided by the remains of what?
Spindle fibres
In order beginning with interphase, what are all the sections of cell division?
Interphase: G1, S, G2 The M Phase: Prophase, Metaphase, Anaphase, Telophase, Cytokinesis
