With Independent Assortment, the Ratio of Phenotypes in the F₂

question 172

Multiple Choice

With independent assortment, the ratio of phenotypes in the F₂ generation of a cross between true-breeding strains (AA bb × aa BB) can be described as 9:3:3:1 when A and B are dominant over a and b. What phenotype does the "9" in the ratio refer to?

• A)recessive for both traits
• B)dominant for the A trait and recessive for the B trait
• C)dominant for one trait and recessive for the other
• D)dominant for both traits

Recognize strategies and treatments for drug addiction.

Understand the biological basis for drug tolerance and withdrawal symptoms.

Comprehend how perception and behavior are influenced by psychoactive drugs.

Acknowledge the societal perceptions and myths regarding drug use.

---

Definitions:

Psychological Therapy

A treatment method for mental and emotional disorders which uses psychological techniques designed to encourage communication of conflicts and insight into problems.

Experimental Research

A scientific method that manipulates one or more variables under controlled conditions to study their effect on a certain outcome.

Independent Variable

In an experiment, the variable that is manipulated or changed to test its effects on the dependent variable.

Drug Dosage

The amount and frequency of a medication that is prescribed or advised to be taken to achieve desired therapeutic effect.