Lipids Metabolism: Lipids, Lipoproteins, Trafficking

Question 1

What lipids are used for cell membranes?
What does it mean to be amphipathic?
What is an esterified Cholesterol?
What lipids are synthesized by the Liver?

Answer 1

phospholipids (amphipathic)
have a charge near hydrophobic group
OH replaced with fatty acid chain
Triglycerides, Cholesterol, Ketone B. phospholipids
(other by other cells)

Question 2

Name 4 functions of Lipids

Answer 2

1. Energy
2. Hormones
3. Solubilizing NP substances in body fluid
4. Supporting alveolar lung integrity

Question 3

Cells that are not liver cells and make cholesterol use it for ______

Answer 3

themselves

Question 4

Most commonly ingested lipids

Answer 4

TG, PL - Phospholipids, CH - cholesterol esterase

Question 5

Bile is a _______, that creates a _______ around ______ particles and allows for _______ to attach and digest

Answer 5

cholesterol derivative
mixed micelle
lipids (non polar)
enzymes

Question 6

Where do they cut? Absorbable Products?

Pancreatic Lipase (2)
Phospholipase A2
Lysophospholipase
Cholesterol Esterase - *formed from ingested cholesterol

Answer 6

hydrolyz-ERS
PL: frees 2 FA, from TG, and PL;
monoGlycerol & Glycerol-phosphorylcholine
PA2: cleaves glycerolphophorylcholine base from ((P))
LPL: frees 1 FA from TG
CE: Cleaves FA from Cholesterol Esterase –> Cholesterol

Question 7

Name the lipid transporters (2)? What do they carry?
What can pass through enterocytes to portal circulation?
Give a general pathway summary of Cholesterol & Long TG
What is packaged into the chylomicron?
Free FA in blood are from where? carried by?
What carrier protein is used to transfer ketone bodies?

Answer 7

FATP4 - Monoglycerides, FA (long) NPCL-1 - Cholesterol
Short/Medium Chain FA
Digested particles absorbed –> reformed in enterocyte –> put in chylomicron –> lymph –> Venous Circ.
Triglycerides, Cholesterol ester.
Stored TG, albumin
none needed

Question 8

Name the pancreatic, exocrine hormones, what stimulates their release?

Does the pancreas secrete bicarbonate? what stimulates?
What stimulates gallbladder release of bile salts?

Answer 8

{pancreatic lipase, phospholipase A2, lysophospholipase, cholesterol esterase} CCK - by Small Intestines

yes; secretin by small intestines

BS: cholecystokinin - CCK by small intestines

Question 9

What is the condition with fat in stool (floating)

Answer 9

Steatorrhea

Question 10

Name the source and apoprotiens on each lipoprotien

Answer 10

Chylomicron (SI) - B48, E, C2; Chylomicron R - B48, E
VLDL (L): B100, E, C2; VDL R (IDL): B100, E
LDL: B100
HDL (SI, L): A-1, E, C2;

Question 11

Cholesterol make a lipoprotein more ________; HDL’s ______ cholesterol before internalization; this prevents the lipoprotien from becoming rigid; The enzyme that catalyzes this reaction is called ______; ______ is the name of the receptor that binds Apo - 1 on liver. Name the special HDL/VDL relationship; What happens to glycerol when lipoportiens are giving up TG

Answer 11

rigid
esterify
LCAT; lecithin
scavenger receptor SR-B1
HDL gives cholesterol to VLDL –> making LDL; also give C2 and E receptors to VLDL
LDL on cells cleaves TG. takes in FA. glycerol enters blood to liver for gluconeogenesis etc.