Question

what portion of a neuron houses the nucleus and other main organelles of a neuron?
a cell body
b dendrites
c axon terminal
d axon

question 4
the primary neurotransmitter of addiction is produced in the ____ and affects the ____.
a prefrontal cortex; limbic system
b nucleus accumbens; limbic system and prefrontal cortex
c cerebellum; nucleus accumbens, prefrontal cortex, and limbic system
d ventral tegmental area; nucleus accumbens, prefrontal cortex, and limbic system
e ventral tegmental area; hippocampus

Explanation:

First Question (Neuron Structure)

To determine the portion of a neuron housing the nucleus and main organelles, we analyze each option:

• Option A (cell body): The cell body (soma) contains the nucleus and organelles like mitochondria, Golgi apparatus, etc., responsible for the neuron’s metabolic functions.
• Option B (dendrites): Dendrites receive signals from other neurons; they do not house the nucleus or main organelles.
• Option C (axon terminal): Axon terminals release neurotransmitters to communicate with other cells; they lack the nucleus and major organelles.
• Option D (axon): The axon transmits electrical signals (action potentials) and does not contain the nucleus or main organelles.

Thus, the cell body is the correct choice.

The primary neurotransmitter of addiction (dopamine) is produced in the ventral tegmental area (VTA). Dopamine from the VTA projects to the nucleus accumbens (reward pathway), prefrontal cortex (decision - making), and limbic system (emotions/memory), driving addictive behaviors. Analyzing the options:

• Option A: Prefrontal cortex does not produce the primary addiction neurotransmitter.
• Option B: Nucleus accumbens is a target, not a production site.
• Option C: Cerebellum is not involved in dopamine production for addiction.
• Option D: Matches the production site (VTA) and target regions (nucleus accumbens, prefrontal cortex, limbic system).
• Option E: Hippocampus is not a primary target of VTA - derived dopamine in addiction.

So, Option D is correct.

Answer:

A. cell body

Second Question (Addiction Neurotransmitter)