Welcome back to the EverythingABUAD study portal! This page is a complete, student-written study companion for PHS 220 – Nervous System: Structure & Function, prepared for ABUAD 200 Level Pharmacy students (Second Semester).
This is the largest topic in the course and the foundation for the special senses guide. Students lose marks by confusing the all-or-none action potential with graded synaptic potentials, and by mixing up the autonomic divisions. Below we break the nervous system down in plain language, flag the high-yield points, and give you original practice questions with worked answers. The full study guide is available in the interactive reader at the end as a free bonus.
- Course: PHS 220 – Physiology II
- College / Department: College of Pharmacy / Pharmacy
- Level / Semester: 200 Level, Second Semester
- Topics covered: Neurons & glia, the action potential, synaptic transmission, brain anatomy, the autonomic nervous system, reflexes
- Best for: Continuous assessment + final exam revision
Topics Covered in PHS 220: Nervous System Structure & Function
1. Neurons & Glial Cells
Neurons are the signalling cells; glia (astrocytes, oligodendrocytes, microglia, Schwann cells) support and insulate them. Exam tip: know that oligodendrocytes myelinate in the CNS while Schwann cells do so in the PNS — a frequently tested distinction.
2. The Action Potential
An action potential fires all-or-none once threshold is reached: voltage-gated sodium channels open for depolarisation, then potassium channels open for repolarisation. Exam tip: describe the phases in order with the channel responsible for each, and contrast the all-or-none spike with graded synaptic potentials.
3. Synaptic Transmission
At the synapse, calcium entry triggers neurotransmitter release; the transmitter binds postsynaptic receptors to produce an excitatory or inhibitory potential. Exam tip: calcium is the trigger for vesicle release — a small but reliably examined fact.
4. Brain Anatomy & the Cortex
Learn the lobes and their functional areas (motor, sensory, visual, auditory, language). Exam tip: be able to predict the deficit from the lesion location — e.g. damage to Broca's vs Wernicke's area produces different language problems.
5. Limbic System & Basal Ganglia
The limbic system handles emotion and memory; the basal ganglia fine-tune movement. Exam tip: link basal ganglia dysfunction to movement disorders (e.g. Parkinsonism) so the function is easy to recall.
6. Spinal Cord, the ANS & Reflexes
The spinal cord carries ascending sensory and descending motor tracts and mediates reflexes; the autonomic nervous system splits into sympathetic ('fight or flight') and parasympathetic ('rest and digest'). Exam tip: tabulate the two autonomic divisions — neurotransmitters, receptors and organ effects — because matching questions are almost guaranteed.
Sample Practice Questions (With Answers)
Here are a few representative questions, written in our own words, with the reasoning explained so you understand the why — not just the answer:
Q. What causes the rapid depolarisation phase of the action potential?
Answer: The opening of voltage-gated sodium channels. Sodium rushes into the cell down its electrochemical gradient, briefly making the inside positive. The phase ends as these channels inactivate and potassium channels open to repolarise the membrane.
Q. Which ion triggers neurotransmitter release at the presynaptic terminal?
Answer: Calcium. When the action potential reaches the terminal, voltage-gated calcium channels open; the calcium influx causes synaptic vesicles to fuse with the membrane and release their neurotransmitter into the synaptic cleft.
Q. Which cells myelinate axons in the central nervous system, and which do so in the periphery?
Answer: Oligodendrocytes myelinate axons in the central nervous system, while Schwann cells myelinate axons in the peripheral nervous system. One oligodendrocyte can myelinate several axons, whereas each Schwann cell myelinates a single segment of one axon.
How to Study PHS 220 (Nervous System Structure & Function) Effectively
- Learn the action-potential phases as an ordered sequence tied to specific ion channels.
- Build one sympathetic-vs-parasympathetic table and review it daily — it pays off across many questions.
- Practise predicting the deficit from a brain lesion's location rather than memorising areas in isolation.
- Understand the concepts here, then drill recall with the workbook before your exam.
Download the Full PHS 220 Nervous System Structure & Function Study Guide
Ready to revise? Use the interactive reader below to read the full nervous system structure & function study guide with diagrams and worked detail. You can read it directly on the page or download it for offline revision before your exam.
Frequently Asked Questions
Is this PHS 220 material free?
Yes — every resource on EverythingABUAD is completely free for ABUAD students.
Does this cover the full PHS 220 syllabus?
This guide covers the nervous system structure & function portion of the PHS 220 syllabus. Work through it alongside the other PHS 220 topic guides on EverythingABUAD, and always cross-check against your lecturer’s current outline.
Will these exact questions appear in my exam?
No. These are original practice questions written for revision only and are not a prediction of the actual exam.
About this resource: All summaries, explanations, study tips, and practice questions on this page were written, paraphrased, and adapted by the EverythingABUAD student team to support exam revision. This is an original study aid, not an official ABUAD document, and it is not a prediction of any future exam.
