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- B1 ✏︎ Molecules -

B1.1 - Carbohydrates (SL/HL)

LECTURE VIDEO

DESCRIPTION

They’re not just pasta—they’re your body’s primary fuel source and a structural marvel. Unwrap the sweet science of carbohydrates for IB Biology. This video breaks down the sugars, from the simplest monosaccharides to the complex polymers. We’ll make it crystal clear:

  • How a glucose molecule is structured (and why its isomerism matters).
  • The difference between glycogen, starch, and cellulose (and why you can digest one but not the other).
  • Why cellulose is the ultimate plant superhero.

Stop cramming and start understanding the energy of life.

TIMESTAMPS

STUDY RESOURCES

00:00 – The Macromolecules

01:21 – Monosaccharide, Disaccharide, & Polysaccharide

03:52 – Digestion Of Glycogen/Starch To Glucose

10:01 – Alpha Glucose Use Overview

11:50 – Hydrolysis & Condensation

14:58 – Alpha Glucose Structure

19:46 – Properties Of Glucose

21:20 – Beta VS Alpha Glucose Structure

23:10 – Quick Recap

23:51 – Ribose

26:06 – Glucose Use: ATP Formation

27:36 – Glycogen Formation (Animals)

34:11 – Starch Formation (Plants)

35:51 – Quick Recap

36:36 – Lactose

39:06 – Sucrose

40:16 – Quick Recap

41:12 – Cellulose

46:07 – Conjugated Molecules

47:28 – Glycoproteins & Function

52:43 – Questions & Answers

54:19 – Summary

NOTES – All you need to know in one place!

QUESTIONS – Test your Big Brain! 

B1.1 - Lipids (SL/HL)

LECTURE VIDEO

DESCRIPTION

They’re not just fats (that give you a triple chin)—they’re insulation, protection, and a powerhouse of energy storage. Dive into the hydrophobic world of lipids for A-Level Biology. This video cuts through the grease to explain:

  • The structure of a triglyceride and why it’s so efficient for storage.
  • The undeniable difference between saturated & unsaturated fats (no confusion!).
  • The amazing dual-nature of the phospholipid and why it’s the foundation of every cell membrane.

Understand the molecules that shape your cells and store your energy.

TIMESTAMPS

STUDY RESOURCES

00:00 – The Macromolecules

01:21 – What Are Lipids?

04:19 – Adipose Tissue

05:14 – Functions Of Lipids

13:53 – Basic Chemistry Knowledge

17:01 – The Fatty Acid

19:57 – Saturated, Mono & Poly Unsaturated

24:24 – Properties Of Fatty Acids

25:31 – Triglycerides Explained (Lipid)

33:11 – Condensation + Hydrolysis

34:23 – Solvent Property Of Lipids

36:06 – Eating & Digesting Triglycerides

38:43 – Phospholipids Explained (Lipid)

43:58 – Cholesterol & Steroid Hormones Explained (Lipid)

49:29 – Questions & Answers

NOTES – All you need to know in one place!

QUESTIONS – Test your Big Brain! 

B1.2 - Proteins (SL/HL)

LECTURE VIDEO

DESCRIPTION

Forget “protein shakes.” Proteins are the original multi-tools of life—they build you, power you, defend you, and control you. But they’re also divas with a fragile ego that can’t handle a little heat or pH change.

This video deconstructs the amazing, versatile, and surprisingly delicate world of proteins, from the tiniest amino acid building block to the functional powerhouse it becomes (and how it can spectacularly unravel).

This video unpacks the protein powerhouse to explain:

  • Amino Acids: The 20-Letter Alphabet of Life: Meet the squad of organic molecules with an amino group, a carboxyl group, and a personality-defining R group.
  • Essential vs. Non-Essential Amino Acids: Why your body can wing some (non-essential) but you absolutely must eat others (essential). It’s the ultimate dietary to-do list.
  • The Condensation Reaction (Peptide Bonding): How amino acids perform a molecular handshake, losing a water molecule to form a dipeptide, then a polypeptide chain. This is how the blueprint becomes a 3D machine.
  • Uses of Proteins: More Than Just Muscle: Are they a building block (structural, enzymes, antibodies)? Absolutely. Are they a last-resort energy source? Sadly, yes—your body will burn its own architecture in a pinch.
  • Denaturation: The Great Unraveling: Why cooking an egg solidifies it, why a fever is dangerous, and why lemon juice “cooks” ceviche. It’s the process of destroying a protein’s delicate 3D shape, turning a precise tool into a useless, tangled mess.

Understand the molecules that do literally everything in your body—and how a bit of heat can turn them into biological scrambled eggs.

TIMESTAMPS

STUDY RESOURCES

00:00 – Intro To Macromolecules

02:02 – DNA Codes For Proteins

03:45 – Examples Of Proteins

09:21 – Amino Acids Form Proteins

12:33 – Essential VS Non-Essential Amino Acids

16:31 – Amino Acid STRUCTURE

22:36 – Linking 2 Amino acids (Peptide Bond)

28:42 – Condensation & Hydrolysis

29:58 – Polypeptide Structure

30:47 – Protein Digestion & Absorption

34:11 – Denaturation & Renaturation

40:17 – IB Questions & Answers

NOTES – All you need to know in one place!

QUESTIONS – Test your Big Brain! 

B1.2 - Proteins (HL)

LECTURE VIDEO

DESCRIPTION

Forget random clumps. Proteins don’t just exist—they perform an intricate, four-act origami routine to become the functional machines of life. Get one fold wrong, and the whole show collapses.

This video unfolds the epic journey of a protein, from a simple linear sequence to a complex, coiled, and sometimes multi-part masterpiece… or a denatured disaster.

This video follows the protein’s structural journey:

  • Primary Structure: The simple, brutal truth. It’s just a specific sequence of amino acids in a chain—the unspooled string of pearls. This sequence dictates everything that follows.
  • Secondary Structure: The first fold. Local coiling into predictable patterns: the elegant Alpha Helix (a molecular spiral staircase) and the pleated Beta Pleated Sheet (a molecular accordion). Held by humble hydrogen bonds.
  • Tertiary Structure: The full, functional 3D glob. The entire polypeptide chain folds in on itself, forming a unique, globular shape via hydrophobic interactions, ionic bonds, and disulfide bridges. This is where it becomes an enzyme or an antibody.
  • Quaternary Structure: The Final Assembly
    • For Collagen (Fibrous): The tough guy. Three separate polypeptide chains twist into a super-strong, rope-like triple helix. It’s the structural steel of your skin, bones, and tendons.
    • For Hemoglobin (Globular): The sophisticated team player. Four separate polypeptide subunits (two alpha, two beta) assemble into a perfect, globular complex that efficiently carries oxygen in your blood.

Witness the precise, layered architecture that turns a simple chain into a molecular machine, from the solo artist to the multi-subunit corporation.

TIMESTAMPS

STUDY RESOURCES

00:00 – DNA Codes For Proteins

01:39 – Diversity In Proteins

02:26 – Amino Acids Structure

04:51 – R-Groups

09:19 – Primary, Secondary, Tertiary & Quaternary Structure

16:04 – Primary Structure Explained

17:36 – Secondary Structure Explained

23:15 – Tertiary Structure Explained

30:55 – Primary Structure determines folding

31:39 – Protein Solubility (Eg Lipase & Glycoprotein)

37:49 – Quaternary Structure Explained

38:21 – Insulin (Unconjugated Protein)

41:01 – Collagen (Unconjugated Protein)

42:08 – Hemoglobin (Conjugated Protein)

44:41 – Globular VS Fibrous Protein

46:07 – Quick Recap

47:08 – Questions & Answers

NOTES – All you need to know in one place!

QUESTIONS – Test your Big Brain! 

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