Growth and Development of Organisms

Organisms growth and development are determined by the ___________________ characteristics that are passed from parent to offspring during reproduction.

• genetic

• environmental

• occasional

Other factors occur outside of the organism and can be related to their access to needed resources, the conditions in their environment, and their responses to other _______________________.

• stimuli

• adaptation

• weather

For plants, these responses are controlled by ___________________, chemicals that affect growth and development.

• tissues

• fertilizers

• hormones

It speeds up the rate at which plant cells grow and controls a plant’s response to light.

• auxin

• dioxin

• myoxine

A plant’s growth response toward or away from a stimulus is called a ____________.

• megaton

• tropism

• auxin

The stems of some plants, such as the vines in the figure, show a response to touch called ________________.

• thigmotropism

• phototropism

• malnotropism

Plants also know which direction to grow, because they respond to gravity. This response is called _______________.

• gravitropism

• thignotropism

• phototropism.

Plants’ response to light is called ______________________. The leaves, stems, and flowers of plants grow toward light.

• thignotropism

• phototropism

• gravitropism

As a vine grows, it coils around any object it touches. This is an example of positive thigmotropism. (True or False)

• True

• False

• unknown

Roots show positive gravitropism if they grow downward. (True or False)

• True

• False

• Not Identified