Twin Studies Help Us Estimate How Much of a Trait

question 52

Multiple Choice

Twin studies help us estimate how much of a trait or behavior is attributable to _____, whereas adoption studies shed light on the extent to which attributes and behaviors are influenced by ______.

• A) genes; the environment
• B) the environment; genes
• C) siblings; parents
• D) random events; a controlled environment

---

Definitions:

Sarcoplasmic Reticulum

A specialized type of smooth endoplasmic reticulum found in muscle cells, which stores and releases calcium ions to trigger muscle contraction.

Skeletal Muscle

A type of striated muscle tissue attached to bones, responsible for voluntary movements of the body.

Smooth Muscle

A type of muscle tissue which is not under voluntary control, found in the walls of internal organs such as the digestive tract, blood vessels, and the bladder.

Cardiac Muscle

A kind of striated muscle that is involuntary and found solely in the heart, tasked with circulating blood throughout the body.