A Researcher Presents Two Lights of Varying Brightness to a Subject

question 655

Multiple Choice

A researcher presents two lights of varying brightness to a subject who is asked to respond same or different as he or she compares the intensities. The researcher is seeking the __________ threshold.

• A)difference
• B)absolute
• C)subliminal
• D)phosphene

---

Definitions:

Branch Roots

Secondary or lateral roots that originate from the primary root, increasing the root system's overall surface area for water and nutrient absorption.

Root Hairs

Thin, hair-like extensions of root epidermal cells that increase surface area for water and nutrient absorption from the soil.

Xylem

is a type of tissue in plants that transports water and dissolved nutrients from the roots to the rest of the plant.

Meristem

Regions in plants where new cells are continuously produced, allowing for plant growth.