ap 2 exam 3

A & P 2 – EXAM 3 (1 APRIL 2026)

CHAPTER 3 — CELLULAR RESPIRATION

1. Know about Glycolysis, intermediate stage, citric acid cycle and electron transport chain

Glycolysis:

• Occurs: cytosol

• Anaerobic (does not require oxygen)

• Breaks glucose into pyruvate

• Produces a small amount of ATP.

• SUBSTRATE: Starting molecule (substrate) = glucose

• PRODUCT = pyruvate

• ATP: 2 net ATP produced

• CO-ENZYME PRODUCED = NADH

Intermediate stage:

• Converts pyruvate into acetyl-CoA in the mitochondria

• Links glycolysis to the citric acid cycle.

• SUBSTRATE: Starting molecule (substrate) = pyruvate

• PRODUCT = acetyl-CoA + CO₂

• ATP: 0 ATP produced

• CO-ENZYME PRODUCED = NADH

Citric acid cycle:

• Occurs in the mitochondrial matrix

• Generates electron carriers (NADH and FADH₂)

• Generates small ATP.

• SUBSTRATE: Starting molecule (substrate) = acetyl-CoA

• PRODUCT = CO₂

• ATP: 2 ATP total

• CO-ENZYME produced = NADH and FADH₂

The electron transport chain:

• Occurs in the cristae (inner mitochondrial membrane)

• Produces most ATP using oxygen (aerobic).

• Regenerates NAD+ so glycolysis can continue

• SUBSTRATE: Starting molecule (substrate) = NADH, FADH₂, oxygen

• PRODUCT = water

• ATP: Most ATP – major source

• CO-ENZYME produced = uses NADH and FADH₂

2. Know about substrate-level phosphorylation

• This is direct ATP production from a substrate.

• Occurs in glycolysis and the citric acid cycle

• Produces small amounts of ATP.

3. Know about oxidative phosphorylation

• This is indirect ATP production using NADH and FADH₂

• Occurs in the electron transport chain.

• Produces most ATP.

4. Know about acetyl-CoA

• Acetyl-CoA is formed from pyruvate and is the entry molecule into the citric acid cycle.

• It connects carbohydrate, fat, and protein metabolism.

5. Describe what happens to pyruvate with insufficient oxygen

• If oxygen is low, pyruvate is converted into lactate.

• This genenrates NAD+ so glycolysis can continue

6 Know pyruvate dehydrogenase

• This enzyme converts pyruvate into acetyl-CoA in the intermediate stage. It is a key control step.

6. Know what pyruvate is (not a enzyme but a molecule)

• Pyruvate is the end product of glycolysis.

• It is a 3-carbon molecule that either enters the mitochondria or becomes lactate.

7. Describe how other fuel molecules like fatty acids and amino acids are utilized to make ATP

• Fatty acids are broken down into acetyl-CoA and enter the citric acid cycle.

• Amino acids are deaminated (nitrogen removed), and their carbon skeleton enters cellular respiration at different points.

• All fuels ultimately feed into the pathway to produce ATP.

🚨 DIRECTLY MENTIONED = EXPECT QUESTIONS

1. Acetyl-CoA

👉 She literally said:

“you’re going to have a test question about acetyl-CoA”

Know:

Formed from pyruvate + CoA (via pyruvate dehydrogenase)

Happens in mitochondria

Required to enter Citric acid cycle

2. Oxaloacetate

👉 She said:

“you’ll have a question on oxaloacetate”

Know:

Combines with acetyl-CoA

Forms citrate

3. Citrate

👉 She tied this directly to the above

Know:

First molecule in Citric acid cycle

Formed from: 👉 acetyl-CoA + oxaloacetate

🚨 HEAVILY EMPHASIZED (WILL BE TESTED INDIRECTLY)

🔥 4. Metabolic pathways + enzymes

She OPENED with this → very important

Know:

Product → becomes next substrate

Multi-enzyme chain

Negative feedback regulation

👉 End product (ATP) shuts pathway off

🔥 5. Allosteric inhibition (PFK)

She repeated this multiple times

Know:

ATP binds enzyme → changes shape

Shuts down glycolysis

👉 This is a classic trick question

🔥 6. ATP vs ADP

She slowed down here → important

Know:

ADP + phosphate → ATP (phosphorylation)

ATP → ADP (dephosphorylation)

👉 reversible

🔥 7. Substrate vs Oxidative phosphorylation

She clearly contrasted these

Know:

Substrate-level = direct (low ATP)

Oxidative = indirect via NADH/FADH₂ (HIGH ATP)

👉 She emphasized: indirect = most ATP

🔥 8. NAD⁺ / NADH

She spent time explaining this

Know:

NAD⁺ = accepts electrons

NADH = carries electrons

Feeds into ETC

👉 Required for ATP production

🔥 9. Glycolysis basics (but focus on control)

She did NOT want steps memorized

Know:

Occurs in cytosol

No oxygen required

2 ATP invested

👉 Control point:

PFK inhibited by ATP

🔥 10. Fate of pyruvate (VERY IMPORTANT)

She used exercise example → big signal

With oxygen:

→ acetyl-CoA → Krebs

Without oxygen:

→ lactate

👉 WHY:

Regenerate NAD⁺

👉 She tied this to:

Muscle soreness

🔥 11. Intermediate stage

She simplified it

Know:

Pyruvate → acetyl-CoA

Produces NADH

Happens twice per glucose

🔥 12. Citric acid cycle(what she cares about)

She said: 👉 don’t memorize steps

👉 focus on key parts

Know:

Location: matrix

Produces:

NADH

FADH₂

ATP

CO₂

👉 Regulation:

Citrate synthase

Controlled by ATP levels

🔥 13. Energy demand regulation

She clearly explained this

High energy demand → ↑ cycle activity

Low energy demand → ↓ cycle activity

👉 ties to ATP levels

🔥 14. Electron Transport Chain (VERY HIGH-YIELD)

She emphasized HARD:

Know:

Location: cristae

Uses:

NADH

FADH₂

🔥 Core mechanism:

Hydrogen pumps

Create gradient

ATP synthase makes ATP

🔥 Oxygen:

👉 final electron acceptor

👉 forms water

🚨 If ETC stops:

No NAD⁺ regeneration

Glycolysis stops

ATP collapses

👉 She explicitly walked through this

🔥 15. ATP Synthase

She highlighted:

👉 builds ATP

👉 uses proton gradient

🔥 16. Fat + protein entry into pathway

She mentioned near the end

Know:

Fats → acetyl-CoA

Proteins → enter at different points

Nitrogen → urea

🚨 VERY HIGH-YIELD SUMMARY (what to memorize cold)

If you ONLY know this, you’re in a strong position:

Acetyl-CoA, oxaloacetate, citrate

ATP inhibits glycolysis (PFK)

NAD⁺ / NADH role

Pyruvate → lactate (no O₂)

ETC = H⁺ gradient + ATP synthase

Oxygen = final electron acceptor

Substrate vs oxidative phosphorylation

Fats/proteins enter pathway

CHAPTER 26 — DIGESTIVE SYSTEM

1. Know organs of the GI tract

• Mouth

• Pharynx

• Esophagus

• Stomach

• Small intestine (duodenum, jejunum, ileum)

• Large intestine

2. Know accessory digestive organs

• Salivary glands (submandibular, sublingual, parotid)

• Liver

• Gallbladder

• Pancreas

3. Know the function of the GI tract

• To break down food into absorbable molecules and move them through the body.

4. Know the function of digestive organs

• Each organ contributes to digestion, absorption, movement, or secretion.

5. Know the stages and functions of the phases of digestion

• Cephalic phase: brain prepares digestion

• Gastric phase: stomach digestion

• Intestinal phase: small intestine digestion and absorption

6. Tunics of the GI wall

• Mucosa (innermost)

• Submucosa

• Muscularis externa

• Serosa (outermost)

8. Describe regulation of the digestive system (ENS, ANS and hormones!)

Systems:

• Enteric nervous system (ENS) – controls digestion locally.

• Autonomic nervous system (ANS) – modifies digestion (parasympathetic increases, sympathetic decreases).

Hormones:

• Gastrin increases secretion (acid) and motility

• Cholecystokinin (CCK) releases bile and pancreatic enzymes

9. Describe serous membranes of the GI tract

They reduce friction and cover organs.

• Visceral peritoneum (innermost)

• Parietal peritoneum (outermost)

10. Describe intraperitoneal organs

• Organs fully surrounded by peritoneum (serous membrane of the GI tract) and suspended by mesentery (organ that anchors intestines to abdominal wall, supplies blood, nerves and houses lymph nodes)

11. Describe retroperitoneal organs

• Organs behind the peritoneum, not fully covered.

12. Individual mesenteries of the abdominopelvic cavity

• They anchor organs and carry blood vessels and nerves.

13. Describe each of the components of the GI tract

• Oral cavity → ingestion, mechanical breakdown, salivary enzymes

• Pharynx → passageway, swallowing

• Esophagus → peristalsis → moves bolus

• Stomach → storage, mixing, protein digestion → chyme

• Small intestine → digestion + major absorption in duodenum

• Large intestine → water and electrolyte absorption, feces formation

14. Describe the anatomy of the GI tract

• Continuous muscular tube from mouth → anus

Layers (tunics 4):

• Mucosa (innermost)

• Submucosa

• Muscularis externa

• Serosa/adventitia (outermost)

Specialized structures:

• Stomach folds (rugae)

• Small intestine → villi + microvilli (these increase surface area and therefore absorption)

15. Describe the histology of the GI tract

Mucosa:

• Epithelium → absorption/secretion

• Lamina propria → connective tissue with blood and lymph vessels

• Muscularis mucosae → smooth muscle for local movement

Submucosa:

• Blood vessels, nerves and glands

Muscularis externa:

• Circular layer → mixing

• Longitudinal layer → movement

Serosa:

• Outer covering

👉 Key idea:

Structure supports digestion + absorption

16. Describe the processes of the GI tract

Ingestion:

• Taking food into the mouth

Motility = movement of food:

• Peristalsis – moving food forward

• Segmentation – mixing

Secretion:

• Release of enzymes

• Release of acid

• Release of bile

• Release of hormones

Digestion = breaking down of food:

• Mechanical (chewing, churning)

• Chemical (enzymes)

Absorption:

• Nutrients enter blood

• Fats enter lymph (lacteals)

Elimination

• Waste removal (feces)

17. Describe the secretions of the GI tract

Saliva:

• Amylase (enzyme that breaks down starch)

• Lingual lipase (enzyme that breaks down lipids)

Stomach cells in the gastric pits:

Parietal cells

• Secrete hydrochloric acid (HCl)

• Secrete intrinsic factor

Chief cells

• Secrete pepsinogen → becomes pepsin (protein digestion)

Mucous cells

• Secrete mucus → protects stomach lining from acid

G cells

• Secrete gastrin (hormone) → increases: acid secretion and motility

Pancreas:

• Releases emzymes like amylase, lipase, proteases

• Bicarbonate (neutralizes acid)

Liver:

• Bile (fat emulsification)

Small intestine:

• Enzymes

• Hormones such as secretin which is released from the duodenum and stimulates the pancreas to release bicarbonate. CCK is also released from the duodenum and contracts gallbladder for bile release, and stimulates pancreas for enzyme secretion

18. Describe the functions of the GI tract

Break down food into absorbable molecules (catabolism)

Absorb nutrients into:

• Blood (most nutrients)

• Lymph (fats)

Maintain fluid balance

Eliminate waste

👉 Core purpose: Food → small molecules → absorption → energy (ATP)

19. Describe the regulation for the oral cavity

• Voluntary control (you choose to eat)

• Salivation reflex: triggered by sight, smell, taste

• Controlled by ANS: parasympathetic nervous system which increases saliva because digestion gets “turned on”

20. Describe the regulation for the salivary glands

• Controlled by ANS

• Parasympathetic (rest and digest) → watery saliva

• Sympathetic (flight or flight) → thicker saliva

Triggered by:

• Food presence

• Sensory input

21. Describe the regulation for the pharynx (throat)

• Controlled by swallowing reflex

• Involuntary phase

• Regulated by the Medulla (brainstem)

• Ensures epiglottis closes airway

• Food directed to esophagus

22. Describe the regulation for the esophagus

• Controlled by peristalsis (reflex)

• Upper esophageal sphincter → voluntary start

• Lower esophageal sphincter: relaxes → allows food into stomach

• Controlled by ANS + ENS

23. Describe the regulation for the stomach

• Controlled by ANS (parasympathetic increases activity)

Hormones: (gastrin)

• Increases HCl secretion

• Increases motility

Triggered by:

• Food in stomach

• Baroreceptors (stretching)

24. Describe each of the components of the lower GI tract

• Small intestine → digestion + absorption

• Liver → produces bile

• Gallbladder → stores/releases bile

• Pancreas → enzymes + bicarbonate

• Large intestine → water and electrolyte absorption, feces

25. Describe the anatomy of the lower GI tract

Small intestine:

• Duodenum, jejunum, ileum

• Villi + microvilli

Liver:

• Largest organ, produces bile

Gallbladder:

• Small sac under liver

Pancreas:

• Behind stomach

Large intestine:

• Cecum → colon → rectum

26. Describe the processes of the lower GI tract

Small intestine:

• Digestion + absorption

Liver:

• Bile production

Gallbladder:

• Bile release and storage

Pancreas:

• Enzyme secretion

Large intestine:

• Water and electrolyte absorption

• Feces formation

27. Describe the secretions of the lower GI tract

• Small intestine → digestive enzymes, hormones

• Liver → bile

• Gallbladder → releases and stores bile

Pancreas:

• Amylase (starch/carbs)

• Lipase (fats)

• Proteases (proteins)

• Bicarbonate

28. Describe the functions of the lower GI tract

• Complete digestion

• Absorb nutrients

• Absorb water

• Form and eliminate feces

• Emulsify fats via bile

29. Describe the regulation for the small intestine

Controlled by:

• ENS (local control)

• ANS

Hormones (CCK)

• Released from duodenum

• Stimulates gallbladder contraction

• Stimulates pancreatic enzyme release

30. Describe the regulation for the liver

Regulated indirectly by hormones:

• CCK (bile release via gallbladder)

Also regulated by:

• Nutrient levels in blood

31. Describe the regulation for the gallbladder

Controlled by CCK

CCK causes:

• Contraction → bile release

32. Describe the regulation for the pancreas

Controlled by:

• CCK → enzyme release

• Secretin → bicarbonate release

Triggered by:

• Chyme entering duodenum

33. Describe the regulation for the large intestine

Controlled by:

• ENS (local reflexes)

• ANS

Functions regulated:

• Water and electrolyte absorption

• Defecation reflex

34. Describe the major classes of macromolecules

• Carbohydrates → sugars/starches → main energy source

• Proteins → amino acids → structure, enzymes

• Lipids (fats) → fatty acids + glycerol → long-term energy

• Nucleic acids → DNA/RNA → genetic material

35. Describe the structures of macromolecules

• Carbohydrates → monosaccharides (e.g., glucose) → linked sugars

• Proteins → chains of amino acids (peptide bonds)

• Lipids → triglycerides (glycerol + 3 fatty acids)

• Nucleic acids → nucleotides (sugar + phosphate + base)

36. Describe the process of the digestion of macromolecules

Carbohydrates:

• Broken down → glucose

Proteins:

• Broken down → amino acids

Lipids:

• Emulsified (bile) → digested → fatty acids

Nucleic acids:

• Broken into nucleotides

👉 Key idea:

Large → small = absorbable

37. Describe the location of digestion of macromolecules

Carbohydrates:

• Mouth (amylase)

• Small intestine

Proteins:

• Stomach (pepsin)

• Small intestine

Lipids:

• Mostly small intestine (lacteals)

Nucleic acids:

• Small intestine

38. Describe the important enzymes in their digestion

Carbohydrates:

• Salivary amylase

• Pancreatic amylase

Proteins:

• Pepsin (stomach)

• Proteases like trypsin and chymotrypsin (come from the pancreas)

Lipids:

• Pancreatic lipase

Nucleic acids:

• Nucleases

39. Describe the three classes of carbohydrates

• Sugars (simple carbs) → quick energy

• Starch (complex carbs) → stored glucose

• Fiber → not digested → helps movement

40. Describe proteins

Made of amino acids

Functions:

• Structure

• Enzymes

• Repair

• Hormones

• Fluid balance

Digestion:

• Broken into amino acids

Excess amino acids:

• Deamination (removal of an amino acid group) – occurs in the liver and urea is eliminated

41. Describe lipids

Made of fatty acids + glycerol

Functions:

• Long-term energy storage

• Insulation

Digestion:

• Bile → emulsifies

• Lipase → breaks down

Absorption:

• Lacteals (lymph) then it enters the bloodstream (fats are too large to enter blood capillaries directly)

42. Describe nucleic acids

DNA and RNA

Made of nucleotides

Digested into:

• Nitrogen bases

• Sugars

• Phosphates

Occurs in:

• Small intestine

🚨 DIGESTIVE SYSTEM — what SHE emphasized (from your lectures)

🔥 1. SMALL INTESTINE = MOST IMPORTANT ORGAN

She emphasized this multiple times

👉 Know:

~90% digestion + absorption happens here

WHY:

Circular folds

Villi

Microvilli

👉 Translation (how she tests):

“Where does most absorption occur?”

“Why is the small intestine so efficient?”

🔥 2. FAT DIGESTION (VERY HIGH-YIELD — SHE REPEATED THIS)

Steps (know in order):

Bile (from liver)

Emulsifies fat

NOT an enzyme

Pancreatic lipase

Digests fat

Absorption

Fats → lacteals (lymph)

Then → bloodstream

👉 She will ask this indirectly:

“Why does lymph flow increase after a fatty meal?”

✔ Because fats enter lacteals

🔥 3. CCK (SHE CLEARLY EMPHASIZED THIS HORMONE)

👉 Released from:

Duodenum

👉 Function:

Contracts gallbladder

Releases bile

Stimulates pancreatic enzymes

👉 Expect:

“What triggers bile release?”

✔ CCK

🔥 4. PANCREAS (REPEATED FUNCTION)

👉 Know:

Releases:

Amylase (carbs)

Lipase (fats)

Proteases (proteins)

Bicarbonate

👉 Bicarbonate:

Neutralizes stomach acid

🔥 5. STOMACH — HCl FUNCTIONS (SHE EMPHASIZED THIS)

👉 Hydrochloric acid:

Activates pepsin

Denatures proteins

Kills microbes

👉 She likes this as a multi-answer concept

🔥 6. PERISTALSIS vs SEGMENTATION (SHE LIKES THIS DISTINCTION)

Peristalsis → movement forward

Segmentation → mixing

👉 Simple but she will twist wording

🔥 7. DIGESTION PURPOSE (FOUNDATION — SHE REPEATED)

👉 Big idea:

Large molecules cannot cross membranes

So:

Carbs → glucose

Proteins → amino acids

Fats → fatty acids

👉 Expect:

“Why is digestion necessary?”

🔥 8. LIVER + GALLBLADDER (LINKED CONCEPT)

Liver → makes bile

Gallbladder → stores bile

👉 Released when:

CCK is present

🔥 9. ABSORPTION PATHWAYS (IMPORTANT CONNECTION)

Most nutrients → blood

Fats → lymph first (lacteals)

👉 She connects this to:

Nutrition

Circulation

🔥 10. MOTILITY + DIGESTION INTEGRATION

She tied this together conceptually:

Motility → moves + mixes

Enzymes → chemically break down

Surface area → absorbs

👉 This is how she builds multi-step questions

CHAPTER 27 — NUTRITION

1. Compare / contrast macronutrients

Provide energy (calories)

Types:

• Carbohydrates

• Lipids

• Proteins

👉 Main role: fuel for ATP

2. Compare / contrast micronutrients

Do NOT provide energy

Types:

• Vitamins

• Minerals

👉 Main role: regulation of body processes

3. Compare / contrast essential nutrients

• Must be obtained from diet

• Body cannot make them

4. Compare / contrast non-essential nutrients

• Body can synthesize them

• Not required from diet

5. Describe the major categories of macronutrients (digestion + use)

Carbohydrates:

• Digestion = broken down into glucose

• Use = primary source of energy + used to produce ATP + stored as glycogen

Lipids:

• Digestion = emulsified by bile + broken down by lipase

• Use = long-term energy storage + insulation and protection + can be converted to acetyl-CoA for ATP

Proteins:

• Digestion = broken down into amino acids

• Use = build and repair tissue + enzymes, hormones, immune function + can be used for energy after deamination

7. Identify dietary sources and examples

Carbohydrates:

• Sugar → fruit, sweets

• Starch → bread, rice

• Fiber → vegetables, whole grains

Lipids:

• Triglycerides → oils, butter

• Saturated fats → animal fats

• Unsaturated fats → plant oils

• Polyunsaturated → fish oils

• Cholesterol → animal products

Proteins:

• Complete (has all the essential 9 amino acids present) → quinoa (planted based), eggs (animal-based)

• Incomplete (missing one of more essential animo acid) → most plant sources, such as beans lentils, peanuts rice, wheat, corn, oats

8. Compare / contrast water-soluble vitamins

• Dissolve in water

• Not stored

• Need regular intake

• Eg: Vitamin C and any B vitamins

9. Compare / contrast how water-soluble vitamins function

• Act as coenzymes

• Help metabolic reactions

10. Compare / contrast fat-soluble vitamins

• Vitamins A, D, E, K

• Absorbed with fats

• Stored in body

11. Compare / contrast how fat-soluble vitamins function

• They are absorbed with fats and transported through lymph (lacteals)

• They are stored in the body (mainly liver and adipose so they don’t need to be consumed daily

A = vision

D = calcium – bones

E = antioxidants

K = clotting

12. Identify important minerals and functions

• Iron → oxygen transport (hemoglobin)

• Calcium → bones, muscle contraction

• Sodium / potassium → nerve signals, fluid balance

• Iodine → thyroid hormones

• Zinc → enzyme function, immunity

13. List the MyPlate items included in a food label

• ½ plate → Fruits + Vegetables

• ¼ plate → Grains (preferably whole grains)

• ¼ plate → Protein

• + Dairy on the side

14. Compare / contrast fed (absorptive) state

• Occurs after eating

• Insulin dominant

• Nutrients stored

15. Compare / contrast how fed state is regulated

Insulin (this is when blood sugar is too high):

• Increases glucose uptake into cells

• Increases glycogen storage

16. Compare / contrast fasting (postabsorptive) state

• Occurs between meals

• Glucagon dominant

• Energy released

17. Compare / contrast how fasting state is regulated

Glucagon (this is when blood sugar is too low)

• Glycogenolysis which takes place in the liver needs to occur, which is breaking glycogen into glucose

• Releases glucose into bloodstream

18. Compare / contrast cholesterol synthesis in the liver

• Liver produces cholesterol

Used for:

• Cell membranes

• Hormones

19. Describe the transport of lipids within the blood

• Lipids transported as lipoproteins

Fats absorbed via:

• Lacteals → lymph → bloodstream

20. Understand how nutrients enter cellular respiration

Carbohydrates

• Broken down into glucose

• Glucose enters glycolysis then continues through intermediate, citric and electron

• Carbs enter at the very beginning

Lipids

• Broken down into fatty acids

• Fatty acids are converted into acetyl-CoA

• Enters at the citric acid level

Proteins

• Broken down into amino acids

• Undergo deamination

• Then enters as pyruvate or enters a section of the citric acid cycle (it can enter at different points of this cycle)

🔥 MOST LIKELY TESTED

1. Fed vs Fasting State (VERY HIGH-YIELD)

Fed (absorptive)

Hormone: insulin

Effect:

Glucose enters cells

Glycogen stored

Fasting (postabsorptive)

Hormone: glucagon

Effect:

Glycogen → glucose (glycogenolysis)

Glucose released into blood

👉 She will NOT ask definition

👉 She WILL ask:

“after a meal what happens?”

“low blood glucose → what pathway activates?”

2. Insulin vs Glucagon (CORE MECHANISM)

Insulin → lowers blood glucose

Glucagon → raises blood glucose

👉 MUST know:

Where glucose is going

Where it’s coming from

3. Lipid transport (ties to digestion)

👉 This is a crossover topic she likes

Fats absorbed → lacteals (lymph)

Then → bloodstream

👉 Expect:

“why don’t fats go directly into blood?”

4. Macronutrients → where they go

She connects this to respiration

Carbs → glycolysis

Fats → acetyl-CoA

Proteins → Krebs

👉 This is integration question territory

5. Complete vs Incomplete proteins

You already caught this ✔

👉 Expect:

Definition

Possibly:

Eggs

Quinoa

6. Water vs Fat-soluble vitamins

She won’t go deep—but:

Know:

Water-soluble:

B + C

Not stored

Fat-soluble:

A, D, E, K

Stored

Absorbed with fat

👉 She may connect this to:

Fat digestion

7. Fat absorption connection

👉 This overlaps with digestion (VERY important)

Bile → emulsifies fat

Lipase → digests

→ lacteals → lymph