Happily Ever After: The Hydra

What does the phrase "almost immortal" from paragraph 1 suggest?

• Hydra is difficult to find.

• Hydra has an odd appearance

• Hydra has super strength.

• Hydra lives for a long time.

Which detail from paragraph 2 suggests that the hydra has regeneration capabilities?

• "These one-inch-long, cylindrical, solitary, plant-like organisms..."

• "Hydra is the common name for animals that are members of the phylum Cnidaria."

• "...slow-moving streams of temerate climates."

• "...they are able to make more stem cells by dividing and producing different cell types, such as those of a limb..."

What are two of the author's purposes for writing the passage?

• to describe medical practices

• to encourage people to collect hydra

• to inform people about hydra

• to persuade people to study hydra

How does the structure of the passage help the reader?

• It explains when scientists first became interested in researching stem cells.

• It describes the process of making new organs from stem cells.

• It explains how the hydra may play a role in solving certain problems.

• It describes the hydra in detail to create a visual image for readers.

Which phrase from paragraph 1 provides a clue to the meaning of the word regeneration as it is used in the passgage?

• "...or a new heart or live sick with cancer..."

• "...disease and accidents won't be a problem for us..."

• "Perhaps sometime in the future..."

• "If we could grow another arm or leg lost in an accident..."

According to the text, why do scientists study hydras?

• because they are trying to improve the life of humanity

• because they are hoping to learn how to change the way human cells function

• because they are trying to discover how to reduce diseases and accidents

• because they want to learn how to improve the performance of different organs.

Which two details should be included in a summary of the passage?

• The hydra is related to jellyfish and corals.

• Cells have particular tasks they perform within the body.

• The hydra can manufacture many stem cells.

• The hydra is a unique animal that is of inerest to scientists.

Read the sentence from the passage. "Galliot calls the hydra a "bag of stem cells' because it constantly can make numerous stem cells from mother stem cells, which constantly produce daughter cells, some remaining identical to the mother stem cells and others becoming more specialized cells." (paragraph 4)

What does the word identical help the reader understand about stem cells?

• Some cells are specialized while others can change jobs as needed.

• Different mother cells produce the same type of daughter cells.

• A cell copies itself to do the same specialized job.

• The daugher cells have the same properties as the mother cells.

Part A. What is the central idea of the passage?

• The biology of hydra may yield medical benefits.

• Humans have a limited number of stem cells.

• Scientists want to increase the human life span.

• The hydra is a common aquatic animal.

Part B. Which sentence from the passage best supports the central idea in Part A?

• "Just a tiny fraction of our adult stem cells remain, such as in those of the skin and hair." (paragraph 4)

• "Perhaps sometime in the future, disease and accidents won't be a problem for us." (paragraph 1)

• "If applied to human cells, we might be programmed to regrow a severed limb or grow a new heart." (pargraph 3)

• "These one-inch-long, cylindrical, solitary, plant-like organisms live in the lakes, ponds,, and slow-moving streams of temperate climates." (paragraph 2)