Which Statement Is Unsubstantiated

question 21

Multiple Choice

Which statement is unsubstantiated?

• A)Intense endurance exercise is associated with the release of three types of endogenous opioids into the blood,of which endorphins are one type.
• B)The hypothesis that released blood chemicals,such as endorphins,is responsible for positive changes in mood and affect is based largely upon logic and not cause and effect research.
• C)Endogenously produced endorphins mimic the effects of injected morphine in rats.
• D)The release of endorphins into the blood stream,during intense aerobic exercise,is responsible for the "runners high" and for positive changes in mood and affect.

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Definitions:

Recessive Trait

A genetic trait that is expressed in offspring only when inherited from both parents, masked by the presence of a dominant trait in a heterozygote.

Genotype

The genetic makeup of an organism, including all of its genes, as opposed to its physical appearance or phenotype.

Tay-Sachs Disease

A genetic disorder characterized by the absence of an enzyme that helps break down fatty substances in the brain, leading to severe neurological impairment and early death.

Autosomal Recessive Disorder

An autosomal recessive disorder is a genetic condition that occurs only when an individual inherits two copies of an abnormal gene, one from each parent.