Chapter 11 The Cell CycleA PPT by Mrs. Morton at Buffalo Acadamy of the Sacred Heart and Andrea Wise of Providence HS

Bacterial Cells

Binary Fission Circular DNA replicates Cell divides

The Cell Cycle Interphase (90% of

cycle) • G1 phase growth • S phase synthesis of DNA • G2 phase preparation for

cell division Mitotic phase • Mitosis nuclear division • Cytokinesis cytoplasm

division

Cell Division: Key Roles Genome: cell’s genetic

information Somatic (body cells) cells Gametes (reproductive cells):

sperm and egg cells Chromosomes: DNA molecules Diploid (2n): 2 sets of

chromosomes Haploid (1n): 1 set of

chromosomes Chromatin: DNA-protein

complex Chromatids: replicated strands

of a chromosome Centromere: narrowing

“waist” of sister chromatids Mitosis: nuclear division Cytokinesis: cytoplasm

division Meiosis: gamete nuclear

division

Chromosomes

Contain genetic information. Made of DNA.

Numbers of chromosomes per cell Humans--46 Total (23 from each parent) Fruit fly- 8 total Chicken--78

The # of chromosomes is not correlated with the complexity of the organism

Chromosomes

MITOSIS

DEFINITION Division of the Cell’s Nucleus

PURPOSE To ensure that each daughter cell

gets an exact copy of the chromosomes

Mitosis

Why cells must divide... List 3 reasons why cells must divide.

1 Growth of organism While each cell remains tiny

2 Repair

3 Reproduce (Mitosis-Asexual, Meiosis Sexual)

Why Cells Must Divide

Mitosis Prophase Metaphase Anaphase Telophase

Prophase Chromosomes

visible Nucleoli

disappear Sister chromatids Mitotic spindle

forms Centrioles move

to opposite poles

Metaphase Centrioles are at

opposite poles Centromeres are

aligned Kinetochores of

sister chromatids attached to microtubules (spindle)

Anaphase Paired centromeres

separate; sister chromatids liberated

Chromosomes move to opposite poles

Each pole now has a complete set of chromosomes

Telophase Daughter nuclei

form Nuclear

envelopes arise Chromatin

becomes less coiled

Two new nuclei complete mitosis

Cytokinesis

Cytoplasmic division

Animals: cleavage furrow

Plants: cell plate

Cell Cycle regulation Cell cycle

control system Checkpoint Cyclin- cell

division protein Levels of cyclins

ebb and flow depending on where in cycle

Cell Cycle regulation Growth factors

Mitosis promoting factor (MPF)- a cyclin

Grows blood vessels to new tissues

Density-dependent inhibition

Anchorage dependence

Cyclins Regulate Cell Cycle

MPF -Mitosis Promoting Factor Contains the enzyme CDK- Cyclin-

Dependent Kinase

Kinase transfers phosphate from ATP to protein (energizes a molecule).

Growth Factors

G1 Checkpoint: External Growth Factors Platelet Derived GF (PDGF)- stimulates

cell division near a wound G2 Checkpoint

Checks the DNA for damage

M -spindle checkpoint Checks the spindle is correctly anchored

to kineticore

Cancer Transformation of DNA Tumor: benign or malignant Metastasis

Cancer: breast cancer cell & mammogram

What phase is this?

What phase is this?

Count cells in the area ofCell division

C C

E e

KARYTYPE

CROSSING OVER- RECOMBINATION FREQUENCY

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Yellow body color

White eye color

Vermilion eye color

Miniature wing

Rudimentary wing

y

y

w

w

v

vm

mr

r

Five characters onX chromosome

0 .01 .31 .34 .58

Wild type

Fig. 13.32(TE Art)

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Duchenne muscular dystrophyBecker muscular dystrophy

Ichthyosis, X-linkedPlacental steroid sulfatase deficiencyKallmann syndromeChondrodysplasia punctata, X-linked recessive

HypophosphatemiaAicardi syndromeHypomagnesemia, X-linkedOcular albinismRetinoschisis

Adrenal hypoplasiaGlycerol kinase deficiency

Incontinentia pigmentiWiskott-Aldrich syndromeMenkes syndrome

Charcot-Marie-Tooth neuropathyChoroideremiaCleft palate, X-linkedSpastic paraplegia, X-linked, uncomplicatedDeafness with stapes fixationPRPS-related gout

Lowe syndrome

Lesch-Nyhan syndromeHPRT-related goutHunter syndromeHemophilia BHemophilia AG6PD deficiency: favismDrug-sensitive anemiaChronic hemolytic anemiaManic-depressive illness, X-linkedColorblindness, (several forms)Dyskeratosis congenitaTKCR syndromeAdrenoleukodystrophyAdrenomyeloneuropathyEmery-Dreifuss muscular dystrophyDiabetes insipidus, renalMyotubular myopathy, X-linked

Androgen insensitivity

Chronic granulomatous diseaseRetinitis pigmentosa-3

Norrie diseaseRetinitis pigmentosa-2

Sideroblastic anemiaAarskog-Scott syndrome

PGK deficiency hemolytic anemia

Anhidrotic ectodermal dysplasia

AgammaglobulinemiaKennedy disease

Pelizaeus-Merzbacher diseaseAlport syndrome

Fabry disease

Albinism-deafness syndrome

Fragile-X syndrome

Immunodeficiency, X-linked,with hyper IgM

Lymphoproliferative syndrome

Ornithine transcarbamylase deficiency

Fig. 13.33(TE Art)