biol 112 cell reproduction and cancer

centorsome

• at pole

• ‘microtubule organising complex’

centriole

pair of spindle fibres

centromere

in the middle of sister chromatids

mitotic spindle

machinery that organises mitosis

aster/astral

anchor for chromosome

metaphase plate

where chromosomes align during metaphase, equator

what happens when sister chromosomes are separated

each becomes a new chromosome

order of mitosis

• interphase

• prophase

• prometaphase

• metaphase

• anaphase

• telophase

non kinetochore microtubules

• polar (from poles)

• cell elongation

• not attached to a kinetochore

kinetochore

on chromosomes where kinetochore microtubules bind

kinesin…

add subunits to polymerise microtubules and push poles apart

dynein

depolymerise mirotubules to pull chromosomes to opposite poles

what does chromatin do at the end of mitosis?

de-condense

in plant cells…

• vesicles form between 2 nuclei

• cell plate forms between

• new cell wall formed

mitogens/growth factors…

regulate cell division

cyclin dependent kinases

expressed internally in response to mitogens to regulate cell division

m phase + G2 phase

M phase

M phase + S,G1

M phase

interphase order

G1, S, G2

M phase includes

mitosis, cytokinesis

G1

• cell grows

• prepares to replicate dna

S phase

• cell grows

• synthesis of dna ready for mitosis

G2

• intact nuclear envelope

• chromosomes replicated - remain indistinct as loosely packed chromatin fibres

• centromeres replicated

• microtubules extend radially forming asters

Prophase

• chromatin fibres condense - formingn discrete chromosomes

• nucleoli disappear

• centrosomes move away from each other

• mitotic spindle begiins to form

prometaphase

• breakdown of nuclear envelope

• some microtubules attach to chromosomes at their kinetochores

• other microtubules interact with those from opposite poles

metaphase

• centrosomes at opposite poles

• chromosomes align on the metaphase plate

• sister kinetochores attached to microtubules coming from opposite poles

anaphase

• begins with separation of centromeres

• sister chromatids move towards opposite poles of the cell

• each chromatid becomes a new chromosome

• poles move further apart

telophase

• elongation of cell by polar microtubules

• daughter nucleoli begin to form at poles of the cell

• nuclear envelope form

• chromatin begins to decondense

what tubules is mitotic spindle made of

• Astral

• Kinetochore

• Non-k inetochore

mitotic spindle function

to organise chromatids along metaphase plate

pulls chromatid pairs apart using microtubule motors

growth factor example

platelet derived growth factor

cancer cells can (regular cells cant)

• grow in multiple layers

• grow without growth factors

• no anchorage dependent growth

• replicate indefinitely

stages of cancer

• initiation mutation

• clonal expansion

• primary tumor

• secondary mutation

• malignancy

• invasion

• metastasize

way to remember stages of cancer

if many cats eat pate then simon must murder infinite mice

g1 checkpoint growth factor

SPF ( sphase promoting factor)

G2 checkpoint growth factor

MPF (mitosis/maturation promoting factor)

metaphase checkpoint growth factor

APC (anaphase promoting complex)

way to remember growth factors at each checkpoint

if it has f at the end it is cyclin dependent

carcinoma

epithelial

sarcoma

connective tissue

myeloma

plasma cells

lymphoma

solid tumor of the lymphatic system

leukaemia

blood

mixed classification

from germ cells/stem cells - can make any type of tissue

how do mitogens regulate cell division

regulating transcription in the nucleus

what happens when mitogens are activated

reception → transduction → response

G1 + S

S

G2 + S

G2

transduction

relay molecules in a signal transduction pathway

T/F all checkpoints are regulated by cyclin dependent kinases

F, metaphase checkpoint regulated by MPF and APC

T/F checkpoints prevent cell cycle progression in the event of incorrect signalling

T

T/F cell cycle regulated by phosphorylation

T

T/F cell cycle can be regulated by ubiquitination

T

Bid

P53 regulator gene

what does p53 regulate

G1 and G2

Bad

in mitochondria

capsases

regulate mitosis in cells

what expresses fas ligand

killer lymphocyte