PORTAGE LEARNING BIOD 101 EXAMS SCRIPT LATEST
QUESTIONS AND ANSWERS GRADED A+
✔✔Cytoskeletal apparatus composed of different types of microtubules to separate
sister chromatids. Includes centrosomes, spindle microtubules, and asters - ✔✔Mitotic
spindle
✔✔Synthesizes ribosomal subunits, breaks down during prophase - ✔✔Nucleolus
✔✔Characteristics of Prophase - ✔✔1. Condensation of chromatin fibers
2. Centrosome movement
3. Formation of mitotic spindle
4. Breakdown of nucleolus
✔✔Characteristics of Prometaphase - ✔✔1. Continued chromatin condensation
2. Changes to nuclear envelope
3. reorganization and changes to mitotic spindle
✔✔kinetochore - ✔✔structured region used for microtubule attachment, face in opposite
directions
✔✔Characteristics of metaphase - ✔✔1. polarization of centrosomes
2. chromosome alignment along equatorial line of cell
3. kinetochore attachment
✔✔metaphase plate - ✔✔symmetrical plane across cell formed by centrosome
placement
✔✔Characteristics of anaphase - ✔✔1. Separation of sister chromatids
2. movement of separated chromatids toward centrosome poles
3. elongation of cell
✔✔Characteristics of telophase - ✔✔1. reformation of nuclei, some organelles, and
nuceoli
2. decondensing of chromosomes
3. dissolution of spindle microtubules
4. mitotic phase completion
5. Cytokinesis
✔✔Cleavage - ✔✔Process through which cytokinesis occurs in animal cells
✔✔Cleavage furrow - ✔✔visible groove along metphase plate of cell. Actin and myosin
interact to contract actin ring like a drawstring and divide the cell
, ✔✔Cell cycle control system - ✔✔molecular surveillance mechanisms that can halt the
cell cycle or allow it to proceed
✔✔Checkpoints - ✔✔places along the cycle where processes are halted and
mechanisms are deployed to ensure cell is ready to proceed to next phase
✔✔cycle locations of checkpoints - ✔✔G1+S, G2+M, metaphase+anaphase
✔✔phosphorylation - ✔✔chemical addition of a phosphate group
✔✔protein kinases - ✔✔enzymes that phosphorylate other proteins to activate or
inactivate them
✔✔cyclin - ✔✔protein that fluctuates in concentration at different phases of the cycle
✔✔-dependent kinases (Cdks) - ✔✔depend on presence of cyclins to become active or
inactive
✔✔MPF (maturation-promoting factor) - ✔✔A cyclin-Cdk complex that causes the cell to
move from interphase into mitosis.
✔✔G1 checkpoint - ✔✔major checkpoint, cell is committed to division after passing
✔✔growth factor - ✔✔protein messenger released from neighboring cells stimulating
nearby cells to divide
✔✔density dependent inhibition - ✔✔cell surface proteins signaling adjoining cells to
stop dividing if too crowded
✔✔anchorage dependence - ✔✔The requirement that to divide, a cell must be attached
to a solid surface.
✔✔G2 checkpoint - ✔✔where newly duplicated DNA is evaluated before division
✔✔M checkpoint - ✔✔Spindle checkpoint, during anaphase, ensures daughter cells will
have correct number of chromosomes
✔✔tumor - ✔✔a mass of abnormal cells within normal body tissues
✔✔benign tumor - ✔✔An abnormal mass of cells that have not developed the ability to
spread to other areas of the body
✔✔malignant tumor - ✔✔a mass of abnormal cells that can grow without restraint and
can spread to other areas of the body
QUESTIONS AND ANSWERS GRADED A+
✔✔Cytoskeletal apparatus composed of different types of microtubules to separate
sister chromatids. Includes centrosomes, spindle microtubules, and asters - ✔✔Mitotic
spindle
✔✔Synthesizes ribosomal subunits, breaks down during prophase - ✔✔Nucleolus
✔✔Characteristics of Prophase - ✔✔1. Condensation of chromatin fibers
2. Centrosome movement
3. Formation of mitotic spindle
4. Breakdown of nucleolus
✔✔Characteristics of Prometaphase - ✔✔1. Continued chromatin condensation
2. Changes to nuclear envelope
3. reorganization and changes to mitotic spindle
✔✔kinetochore - ✔✔structured region used for microtubule attachment, face in opposite
directions
✔✔Characteristics of metaphase - ✔✔1. polarization of centrosomes
2. chromosome alignment along equatorial line of cell
3. kinetochore attachment
✔✔metaphase plate - ✔✔symmetrical plane across cell formed by centrosome
placement
✔✔Characteristics of anaphase - ✔✔1. Separation of sister chromatids
2. movement of separated chromatids toward centrosome poles
3. elongation of cell
✔✔Characteristics of telophase - ✔✔1. reformation of nuclei, some organelles, and
nuceoli
2. decondensing of chromosomes
3. dissolution of spindle microtubules
4. mitotic phase completion
5. Cytokinesis
✔✔Cleavage - ✔✔Process through which cytokinesis occurs in animal cells
✔✔Cleavage furrow - ✔✔visible groove along metphase plate of cell. Actin and myosin
interact to contract actin ring like a drawstring and divide the cell
, ✔✔Cell cycle control system - ✔✔molecular surveillance mechanisms that can halt the
cell cycle or allow it to proceed
✔✔Checkpoints - ✔✔places along the cycle where processes are halted and
mechanisms are deployed to ensure cell is ready to proceed to next phase
✔✔cycle locations of checkpoints - ✔✔G1+S, G2+M, metaphase+anaphase
✔✔phosphorylation - ✔✔chemical addition of a phosphate group
✔✔protein kinases - ✔✔enzymes that phosphorylate other proteins to activate or
inactivate them
✔✔cyclin - ✔✔protein that fluctuates in concentration at different phases of the cycle
✔✔-dependent kinases (Cdks) - ✔✔depend on presence of cyclins to become active or
inactive
✔✔MPF (maturation-promoting factor) - ✔✔A cyclin-Cdk complex that causes the cell to
move from interphase into mitosis.
✔✔G1 checkpoint - ✔✔major checkpoint, cell is committed to division after passing
✔✔growth factor - ✔✔protein messenger released from neighboring cells stimulating
nearby cells to divide
✔✔density dependent inhibition - ✔✔cell surface proteins signaling adjoining cells to
stop dividing if too crowded
✔✔anchorage dependence - ✔✔The requirement that to divide, a cell must be attached
to a solid surface.
✔✔G2 checkpoint - ✔✔where newly duplicated DNA is evaluated before division
✔✔M checkpoint - ✔✔Spindle checkpoint, during anaphase, ensures daughter cells will
have correct number of chromosomes
✔✔tumor - ✔✔a mass of abnormal cells within normal body tissues
✔✔benign tumor - ✔✔An abnormal mass of cells that have not developed the ability to
spread to other areas of the body
✔✔malignant tumor - ✔✔a mass of abnormal cells that can grow without restraint and
can spread to other areas of the body
