Tubulin Labeled with Caged Fluorescein Can Be Introduced into Dividing

question 25

Short Answer

Tubulin labeled with caged fluorescein can be introduced into dividing cells by microinjection. Various small regions in the mitotic spindle (made up of tubulin subunits) are briefly irradiated with laser light that uncages the fluorescent tubulin. Five minutes after irradiation, the highest spindle fluorescence is observed when the irradiated region is close to the chromosomes near the cell equator, and the lowest fluorescence is observed when regions near the spindle poles are irradiated. Based on this observation, do you think tubulin subunits are incorporated into the spindle mostly near the poles (P) or near the equator (E)? Write down P or E as your answer.

---

Definitions:

Purchased Patents

Intellectual property rights acquired from another entity, granting exclusive rights to use, make, sell, or distribute the patented technology or product.

Gain On Sale

The profit that results from selling an asset for more than its purchase price.

Net Income

The total earnings or profit of a company after all expenses and taxes have been deducted from total revenue.

Retirement Of Debt

The process of paying off or settling a debt obligation, either through periodic payments over time or a lump sum payment.