Figure 12.5-3 Chromosomal Chromosomes DNA molecules 1 Centromere Chromosome arm Chromosome duplication (including DNA replication) and condensation 2 Sister chromatids Separation of sister chromatids into two chromosomes 3
Figure 12.14 EXPERIMENT Experiment 1 Experiment 2 S G1 M G1 RESULTS S S M M When a cell in the S When a cell in the phase was fused M phase was fused with with a cell in G1, a cell in G1, the G1 the G1 nucleus nucleus immediately immediately entered began mitosis—a spindle the S phase—DNA formed and chromatin was synthesized. condensed, even though the chromosome had not been duplicated.
Figure 12.17 M G1 S G2 M G1 S G2 M G1 MPF activity Cyclin concentration Time (a) Fluctuation of MPF activity and cyclin concentration during the cell cycle 1 S G Cdk M Degraded 2 G cyclin G2 Cdk Cyclin is checkpoint degraded Cyclin MPF (b) Molecular mechanisms that help regulate the cell cycle
Figure 12.18 1 A sample of human Scalpels connective tissue is cut up into small pieces. Petri dish 2 Enzymes digest the extracellular matrix, resulting in a suspension of free fibroblasts. 4 PDGF is added 10 µm 3 Cells are transferred to to half the culture vessels. vessels. Without PDGF With PDGF
Figure 12.20 Lymph vessel Tumor Blood vessel Glandular Cancer tissue cell Metastatic tumor 1 A tumor grows 2 Cancer 3 Cancer cells spread 4 Cancer cells from a single cells invade through lymph and may survive cancer cell. neighboring blood vessels to and establish tissue. other parts of the a new tumor body. in another part of the body.