Chromatin
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Chromosomes
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sister chromatid
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Centromere
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kinetochore
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centrosome
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centriole
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somatic cells
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gametic cells
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mitosis
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cytokinesis
division of cytoplasm, cell divides into two. Animal cell- cleavage furrow forms. Plant cell- cell plate forms
G1 checkpoint
checks for nutrients, growth factors, DNA damage, most important checkpoint
G2 checkpoint
checks for cell size and DNA replication
interphase
cell spends 90% of time here, cell growth, DNA replication, preparation for division, organelle replication
G0
resting state after G1 checkpoint, cells do this when not ready to move on in the process
DNA sythesis
DNA is replicated in the stage
metaphase checkpoint
checks for spindle attachment
Mitotic phase (mitosis)
5 suphases
* prophase
* prometaphase
* metaphase
* anaphase
* telophase
prophase
nucleoli disappear, chromatin condense into chromosomes, mitotic spindle begins to form in the cytoplasm, centrosomes (with centrioles) move away from each other
prometaphase
nuclear envelope disappears, bundles of microtubules extend from each pole towards equator of cell, some microtubules attach to kinetochores
Metaphase
centrosomes are at opposite poles, chromosomes line up on metaphase plate, mitotic spindle is fully formed
anaphase
sister chromatids seperate at centromere, chromatids move towards pole, each becomes own chromosome, cell becomes more oval in shape
Telophase
daughter nuclei begin to form at poles of cell, nuclear envelopes reform, nucleoli reappear, chromatin becomes less condensed, chromosomes disappear
growth factor
substance that is required for certain cells to divide
MPF (maturation promoting factor)
specific type of cyclin-Cdk, master switch for cell's passage from interphase to mitosis
cancer
results from uncontrolled cell division, ignores density-dependent inhibition, continue to divide as long as they have nutrients, single cells undergoes transformation
tumor
forms if cell evades destruction after transformation, mass of cancer cells within an otherwise normal tissue
benign tumor
cancerous cells remain in one spot, some of these tumors are not cancerous or life threatening (warts)
malignant tumor
becomes invasive enough to impair functions of one or more organs (carcinoma, sarcoma, lymphoma)