Week 14 — Readings & Resources · The Peripheral & Autonomic Nervous System

Course: Anatomy & Physiology I (BIOL 2301 + BIOL 2101) · Silver Oak University (fictional sample) · Prof. Navarro
Objective covered: Objective 7 — Describe the organization of the nervous system (CNS, PNS, ANS); contrast the sympathetic and parasympathetic divisions.

How to use this page

Everything here is a link to an external resource — open it in your browser, the same way you'd open a YouTube link. Nothing needs to be downloaded.

This week's load is deliberately light: 1 video + 2 short readings + 1 interactive atlas, grouped by the ideas from the lecture. Watch or read one item per group and you're ready for the quiz; do all of them and you'll be very comfortable. Total time is roughly 35–45 minutes if you do everything, far less if you pick one per group.

Order that matches the lecture: ① the PNS — cranial & spinal nerves, afferent/efferent, somatic/autonomic → ② the autonomic system: sympathetic vs. parasympathetic → ③ explore the nerves on a virtual atlas.

A habit to start now: before you trust any A&P claim — in these resources, in a chatbot, or anywhere — ask the questions from class: Is this effect fight-or-flight (sympathetic) or rest-and-digest (parasympathetic)? Is the signal afferent (sensory, in) or efferent (motor, out)? Voluntary (somatic) or involuntary (autonomic)?

① The Peripheral Nervous System — Cranial & Spinal Nerves, Somatic vs. Autonomic

Maps to Lecture Segments 2–4. The CNS is the brain and spinal cord; everything else — 12 cranial + 31 spinal nerve pairs — is the PNS. Signals run in two directions (afferent/sensory, efferent/motor), and the motor side splits into voluntary (somatic) and involuntary (autonomic).

Reading — "Anatomy and Physiology 2e," Ch. 13 Introduction & the nervous-system overview (OpenStax)
🔗 https://openstax.org/books/anatomy-and-physiology-2e/pages/13-introduction
Why it's assigned: the cleanest plain-language statement that the nervous system controls the body through somatic (voluntary) and autonomic (involuntary) functions, and the framework for the central vs. peripheral divisions. A free online textbook page, no account needed. (Use the "Next" links to step into the regional anatomy of the cranial and spinal nerves.)
⏱ ~10 min

Interactive reading — InnerBody "The Nervous System" (free, no download)
🔗 https://www.innerbody.com/image/nervov.html
Why it earns the click: a clear, free walkthrough that explicitly lays out afferent (sensory) vs. efferent (motor) neurons, the 12 pairs of cranial nerves and 31 pairs of spinal nerves, and the somatic vs. autonomic split — with the sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) divisions defined side by side. Scroll to "Divisions of the Nervous System." You'll also use this atlas in Lab 14.
⏱ ~12 min (read the divisions section)

② The Autonomic Nervous System — Sympathetic vs. Parasympathetic

Maps to Lecture Segments 5–6. The headline of the week: two antagonistic branches. Sympathetic = fight-or-flight (↑ heart rate, dilates pupils, inhibits digestion). Parasympathetic = rest-and-digest (↓ heart rate, constricts pupils, stimulates digestion; the vagus nerve).

Video — "Autonomic Nervous System" (CrashCourse Anatomy & Physiology #13)
🔗 https://www.youtube.com/watch?v=71pCilo8k4M
Why it earns the click: an energetic ~9-minute tour of exactly our headline — how the sympathetic and parasympathetic systems work as foils that balance each other, why one is "fight or flight" and the other "rest and digest," and where their nerve fibers originate. Watch the whole thing; it nails the contrast the quiz, lab, and assignment all turn on.
⏱ ~9 min

Reading — "Anatomy and Physiology 2e," §15.1 Divisions of the Autonomic Nervous System (OpenStax)
🔗 https://openstax.org/books/anatomy-and-physiology-2e/pages/15-1-divisions-of-the-autonomic-nervous-system
Why it's assigned: the single best reference for the sympathetic (fight-or-flight, thoracolumbar) vs. parasympathetic (rest-and-digest, craniosacral) divisions, the dual innervation of organs like the heart (one branch speeds it, the other slows it), and the chemical messengers (norepinephrine vs. acetylcholine). It also explains the vagus nerve's parasympathetic role. Read the opening and the two division sections; the rest is detail beyond our scope.
⏱ ~12 min

③ Explore the Nerves (free virtual atlas)

Maps to Lecture Segment 8 + Lab 14. See where the cranial and spinal nerves emerge, and find the vagus nerve's path to the heart and gut.

Interactive — InnerBody "Anatomy Explorer," Nervous System (free, no download)
🔗 https://www.innerbody.com/image/nervov.html
Why it earns the click: the same clickable atlas from group ①, used here to locate structures — where the cranial nerves leave the brain, where the spinal nerves exit along the cord, and the vagus nerve's wandering route. Spend five minutes getting comfortable before the lab.
⏱ ~5 min (browse)

Optional one-stop references (free online)

• Khan Academy — Human Anatomy & Physiology. A free unit with short articles and videos covering the nervous system, including the autonomic divisions. A good place to return to all term.
  🔗 https://www.khanacademy.org/science/health-and-medicine/human-anatomy-and-physiology
• GetBodySmart — interactive A&P tutorials. Clean, labeled, interactive diagrams of the nervous system; handy when you want to drill structure names and pathways.
  🔗 https://www.getbodysmart.com/

Pick-one quick path (≈20 min total)

In a hurry? Do exactly these two and you'll be ready for the quiz:
1. Watch "Autonomic Nervous System" (CrashCourse A&P #13 — the sympathetic/parasympathetic contrast in one video).
2. Skim OpenStax §15.1 Divisions of the Autonomic Nervous System (the two branches, dual innervation, and the vagus — the heart of the quiz).

Heads-up (links rot): these point to outside sites that occasionally move or rename pages. If a link ever fails, tell Prof. Navarro and use the OpenStax or Khan Academy references above in the meantime.