Normal Cells and Cancer Cells

Wound healing and mitotic rates in the damaged cornea of a mouse. The level of DNA

replication in corneal epithelial cells in mice is high in the morning and low in the

afternoon/evening. As a consequence, injury in the morning is expected to lead to accelerated

entry into mitosis and wound repair compared to injury in the afternoon/evening. Shaded

areas indicate dark periods and ZT stands for Zeitgeber Time (24 hour period).

Based on the information provided, when is the level of DNA replication higher in mice eye

cells? (1 point)

• morning

• its always the same

• evening

Tags

NGSS.HS-LS1-4

Wound healing and mitotic rates in the damaged cornea of a mouse. The level of DNA replication in corneal epithelial cells in mice is high in the morning and low in the

afternoon/evening. As a consequence, injury in the morning is expected to lead to accelerated

entry into mitosis and wound repair compared to injury in the afternoon/evening. Shaded

areas indicate dark periods and ZT stands for Zeitgeber Time (24 hour period).

Overall, during which time is the rate of cell division higher? (1 point)

• Healing-delayed phase

• it is the same in both phases

• healing-accelerating phase

Tags

NGSS.HS-LS1-4

Wound healing and mitotic rates in the damaged cornea of a mouse. The level of DNA replication in corneal epithelial cells in mice is high in the morning and low in the

afternoon/evening. As a consequence, injury in the morning is expected to lead to accelerated

entry into mitosis and wound repair compared to injury in the afternoon/evening. Shaded

areas indicate dark periods and ZT stands for Zeitgeber Time (24 hour period).

What is the total number of dividing cells at a ZT time of 1? (1 point)

• 175

• 350

• 300

• 225

Tags

NGSS.HS-LS1-4

Which type of cell growth results in more cells being produced? (1 point)

• cancer cel growth

• normal cell growth

Which of the following is true of the two types of cell growth? (1 point)

• normal cells cannot control their growth

• cancer cells grow at a slower rate than normal cells

• cancer cells grow at a faster rate than normal cells

• normal cell growth results in more cels being produced

Which of the following seems to have caused the cells to become cancerous? (1 point)

• two copies of the mutated suppressor gene

• the amount of mutation they have

• their color

Tags

NGSS.HS-LS3-2