Pathology (Robbins) Chapter 3 - Part 2 of 2, Tissue
Renewal and Repair: Regeneration, Healing, and
Fibrosis
1. 9 An experiment analyzes factors involved in the cell cycle during
growth factor-induced cellular regeneration in a tissue culture. Cyclin B
synthesis is induced; the cyclin B binds and activates cyclin-dependent
kinase 1 (CDK1). The active kinase produced by this process is most likely
to control progression in which of the following phases of the cell
cycle?
□ (A) G0 to G1
□ (B) G1 to S
□ (C) S to G2
□ (D) G2 to M
□ (E) M to G1
5 (D) G2 to M : CDK1 controls an extremely important transition point,
the G2 to M transition during the cell cycle, which can be regulated by
CDK inhibitors. The other checkpoints are regulated by a distinct set of
proteins.
,1. 10 An experiment is conducted involving cellular aspects of wound
healing. Components of the extracellular matrix are analyzed to
determine their sites of production and their binding patterns to other
tissue components. Which of the following molecules synthesized by
fibroblasts can best bind to cellular integrins and extracellular collagen
and attach epidermal basal cells to basement membrane?
□ (A) Heparin
□ (B) Dermatan sulfate
□ (C) Procollagen
□ (D) Fibronectin
□ (E) Hyaluronic acid
1 0 (D) Fibronectin is a key component of the extracellular matrix and
has a structure that looks like a paper clip. Fibronectin can be
synthesized by monocytes, fibroblasts, and endothelium.
Heparin that is infused has an anticoagulant function.
Dermatan sulfate, a glycosaminoglycan, acts to form a gel that provides
resilience and lubrication.
Procollagen produced by fibroblasts is formed into ropelike strands of
collagen, which provide tensile strength.
Hyaluronic acid binds water to form a gelatinous extracellular matrix.
, 1. 11 An 18-year-old man lacerated his left hand and required sutures. The
sutures were removed 1 week later. Wound healing continued, but the
site became disfigured by a prominent raised, nodular scar that
developed over the next 2 months. Which of the following terms best
describes the process that occurred during this 2-month period?
□ (A) Organization
□ (B) Dehiscence
□ (C) Resolution
□ (D) Keloid formation
□ (E) Secondary union
1 1 (D) Keloid formation: The healing process sometimes results in an
exuberant production of collagen, giving rise to a keloid. This tendency
may run in families.
Organization occurs as granulation tissue is replaced by fibrous tissue.
Dehiscence occurs when a wound pulls apart. If normal tissue
architecture is restored, resolution of inflammation has occurred.
Secondary union describes the process by which large wounds fill in
and contract.
Renewal and Repair: Regeneration, Healing, and
Fibrosis
1. 9 An experiment analyzes factors involved in the cell cycle during
growth factor-induced cellular regeneration in a tissue culture. Cyclin B
synthesis is induced; the cyclin B binds and activates cyclin-dependent
kinase 1 (CDK1). The active kinase produced by this process is most likely
to control progression in which of the following phases of the cell
cycle?
□ (A) G0 to G1
□ (B) G1 to S
□ (C) S to G2
□ (D) G2 to M
□ (E) M to G1
5 (D) G2 to M : CDK1 controls an extremely important transition point,
the G2 to M transition during the cell cycle, which can be regulated by
CDK inhibitors. The other checkpoints are regulated by a distinct set of
proteins.
,1. 10 An experiment is conducted involving cellular aspects of wound
healing. Components of the extracellular matrix are analyzed to
determine their sites of production and their binding patterns to other
tissue components. Which of the following molecules synthesized by
fibroblasts can best bind to cellular integrins and extracellular collagen
and attach epidermal basal cells to basement membrane?
□ (A) Heparin
□ (B) Dermatan sulfate
□ (C) Procollagen
□ (D) Fibronectin
□ (E) Hyaluronic acid
1 0 (D) Fibronectin is a key component of the extracellular matrix and
has a structure that looks like a paper clip. Fibronectin can be
synthesized by monocytes, fibroblasts, and endothelium.
Heparin that is infused has an anticoagulant function.
Dermatan sulfate, a glycosaminoglycan, acts to form a gel that provides
resilience and lubrication.
Procollagen produced by fibroblasts is formed into ropelike strands of
collagen, which provide tensile strength.
Hyaluronic acid binds water to form a gelatinous extracellular matrix.
, 1. 11 An 18-year-old man lacerated his left hand and required sutures. The
sutures were removed 1 week later. Wound healing continued, but the
site became disfigured by a prominent raised, nodular scar that
developed over the next 2 months. Which of the following terms best
describes the process that occurred during this 2-month period?
□ (A) Organization
□ (B) Dehiscence
□ (C) Resolution
□ (D) Keloid formation
□ (E) Secondary union
1 1 (D) Keloid formation: The healing process sometimes results in an
exuberant production of collagen, giving rise to a keloid. This tendency
may run in families.
Organization occurs as granulation tissue is replaced by fibrous tissue.
Dehiscence occurs when a wound pulls apart. If normal tissue
architecture is restored, resolution of inflammation has occurred.
Secondary union describes the process by which large wounds fill in
and contract.
