Week 3 — Readings & Resources · Biological Macromolecules

Course: Introduction to Biology — General Biology I (BIOL 101) · Silver Oak University (fictional sample) · Prof. Castellano
Objective covered: Objective 2 — Apply the chemistry of life to the four classes of biological macromolecules, explaining how structure determines function.

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: 2 short videos + 2 short readings, grouped by the ideas from the lecture, plus optional free online references. 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 40–50 minutes if you do everything, far less if you pick one per group.

Order that matches the lecture: ① the big picture — monomers, polymers & the four classes → ② carbohydrates & lipids → ③ proteins & protein structure → ④ nucleic acids (DNA vs. RNA).

A habit to start now: before you trust any biology claim — in these resources or anywhere — ask the question from class: what's the structure, and how does it create the function?

① The Big Picture · Monomers, Polymers & the Four Classes

Maps to Lecture Segments 1–2. Life is built from four macromolecule families (carbohydrates, lipids, proteins, nucleic acids); cells build polymers by dehydration synthesis and break them by hydrolysis.

Video — "Biomolecules" (Amoeba Sisters)
🔗 https://www.youtube.com/watch?v=YO244P1e9QM
Why it earns the click: a friendly ~7-minute tour of exactly the four molecules we built on the board — monomers, carbohydrates, lipids, proteins, and nucleic acids — with the same "what's its job?" framing. Watch the first two minutes for monomers and you've got Segment 2.
⏱ ~7 min

Reading — "Synthesis of Biological Macromolecules" (OpenStax Biology 2e, §3.1)
🔗 https://openstax.org/books/biology-2e/pages/3-1-synthesis-of-biological-macromolecules
Why it's assigned: the cleanest plain-language version of monomers, polymers, and the two reactions — dehydration synthesis builds (removes water) and hydrolysis breaks (adds water) — with the glucose-to-maltose example we did in class. Free to read online, no account needed.
⏱ ~8 min

② Carbohydrates & Lipids

Maps to Lecture Segments 3–4. Carbohydrates run from quick fuel (glucose) to structural fiber (cellulose); lipids store energy and build membranes — and lipids are not polymers.

Video — "Biological Molecules — You Are What You Eat" (CrashCourse Biology #3)
🔗 https://www.youtube.com/watch?v=H8WJ2KENlK0
Why it earns the click: Hank walks through carbohydrates, lipids, and proteins through the food you eat — the same everyday angle we used with the nutrition label. Great for the carbs-vs-fats "energy and structure" story.
⏱ ~12 min

Reading — "Carbohydrates" (OpenStax Biology 2e, §3.2)
🔗 https://openstax.org/books/biology-2e/pages/3-2-carbohydrates
Why it's assigned: covers monosaccharides → polysaccharides and the exact starch vs. cellulose "same glucose, different linkage, different job" comparison that anchors this week's structure→function theme. (Lipids are the next section, §3.3, if you want it: 🔗 https://openstax.org/books/biology-2e/pages/3-3-lipids)
⏱ ~10 min

③ Proteins & Protein Structure

Maps to Lecture Segments 5–6. Proteins do almost every job in the cell, and a protein's function comes from its shape, which comes from its amino-acid sequence — the four levels of structure, and why one wrong amino acid (sickle cell) matters.

Reading — "Proteins" (OpenStax Biology 2e, §3.4)
🔗 https://openstax.org/books/biology-2e/pages/3-4-proteins
Why it's assigned: lays out amino acids, the peptide bond, the four levels of protein structure (primary → secondary → tertiary → quaternary), denaturation, and the sickle-cell one-amino-acid example — the core of Segments 5–6. Read the "Protein Structure" section closely.
⏱ ~12 min

Enzymes are proteins, too (optional, ~5 min): Amoeba Sisters — "Enzymes (Updated)," a quick look at how a protein's shape (its active site) creates its function, and what denaturation does to it: 🔗 https://www.youtube.com/watch?v=qgVFkRn8f10

④ Nucleic Acids — DNA vs. RNA

Maps to Lecture Segment 7. Nucleic acids store and transmit the instructions for building proteins; DNA and RNA differ in strands, sugar, and one base (T vs. U).

Reading — "Nucleic Acids" (OpenStax Biology 2e, §3.5)
🔗 https://openstax.org/books/biology-2e/pages/3-5-nucleic-acids
Why it's assigned: the clearest side-by-side of DNA vs. RNA — double vs. single strand, deoxyribose vs. ribose, and the A-T-G-C / A-U-G-C base difference — plus how nucleotides carry the genetic blueprint. This is the bridge to the molecular-biology weeks later in the term.
⏱ ~10 min

Optional one-stop references (free online)

• Khan Academy — Chemistry of Life (AP Biology). A free unit with short articles and videos on macromolecules — monomers/polymers, carbohydrates, lipids, proteins, and nucleic acids. A good place to return to all term.
  🔗 https://www.khanacademy.org/science/ap-biology/chemistry-of-life
• Khan Academy — "Introduction to macromolecules" (article). A tight written overview of the four classes and how monomers form polymers — handy for a quick reread before the quiz.
  🔗 https://www.khanacademy.org/science/ap-biology/chemistry-of-life/introduction-to-biological-macromolecules/a/introduction-to-macromolecules

Pick-one quick path (≈19 min total)

In a hurry? Do exactly these two and you'll be ready for the quiz:
1. Watch "Biomolecules" (Amoeba Sisters — groups ①–②).
2. Read the "Protein Structure" section of "Proteins" (group ③) and skim the DNA vs. RNA table in "Nucleic Acids" (group ④).

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