How are lipids transported around the body, what apolipoproteins make up these lipoproteins,
where are they transporting the lipids?
Chylomicrons
VLDL, LDL, HDL
Adipose tissue released FAs correct answers Chylomicron is the lipoprotein that is made in the
intestinal epithelial cell and secreted into the Lymphatic system and the thoracic duct before
entering the blood stream. Is it made by Apolipoprotein B48 surrounding a group of TAGs
HDL: ApoE, ApoCII, ApoA
VLDL, LDL: Apo100 & TAGs
Fatty acids release by the adipose tissue bind to albumin for transport in the blood
Lipolysis correct answers TAG to 3 FA + GLycerol
Beta Oxidation correct answers FA to Acetyl CoA
TCA cycle correct answers Acetyl CoA to 2 CO2
Ketogenesis correct answers 2 Acetyl CoA to Acetoacetate or Beta-Oh Butyrate
Ketolysis correct answers Acetoacetate or β-OH butyrate → 2 Acetyl CoA
Lipogenesis correct answers 3 FA + Glycerol → TAG
FA Synthesis correct answers Acetyl CoA or Malonyl CoA → FA
Gluconeogenesis correct answers Malate → Glucose
Glycolysis correct answers Glucose → Pyruvate
How are fatty acids released from adipose tissue transported around the body? correct answers
Fatty acids are released from adipose by hydrolysis of their stored form, triacylglycerol. After
release from adipocytes, unesterified fatty acids are transported in the blood bound to serum
albumin to tissues such as liver, heart and muscle, where they are taken up and oxidized
Why can't β-oxidation and fatty acid synthesis occur at the same time in any tissue? correct
answers Beta oxidation breaks down fatty acids and fatty acid synthesis creates fatty acids both
pathways can't happen at the same time because it would be energetically inefficient
Also malonyl CoA that is formed during fatty acid synthesis inhibits CPT1 which stops the
progression of beta oxidation
, Explain the role of electron transport chain and oxidative phosphorylation in regulating flux
through β-oxidation, TCA cycle, Ketogenesis. correct answers If there is an increase in ATP,
then there will be a decrease of ADP which mean hydrogens won't be able to be pumped through
ATP Synthase channel and the reverse reactions will take place.
Think about the advantage of producing β-OH butyrate instead of acetoacetate if you are the
liver. What is the advantage to the brain? correct answers Liver: live like to provide energy to the
body. β-OH butyrate is an essential carrier of energy from the liver to peripheral tissues when the
supply of glucose is too low for the body's energetic needs
Brain: β-OH butyrate is able to cross the blood-brain-barrier into the central nervous system and
provide the brain with energy
Please list the pathways that are active in the tissues listed below in the postprandial
(immediately after a meal) carnivore and omnivore (30).
Pathways: glycolysis, gluconeogenesis, glycogenolysis, glycogenesis, lipolysis, lipogenesis, fatty
acid synthesis, and β-oxidation correct answers Liver
Ruminant: Gluconeogenesis, Glycogenolysis, TCA Cycle, Ketogenesis
Monogastric Herbivore: Glycolysis, Glycogenesis, TCA Cycle,
FA Synthesis, Lipogenesis
Muscle
Ruminant: TCA Cycle, Lipolysis
Monogastric Herbivore: Glycolysis, Glycogenesis, TCA Cycle, Lipogenesis
Adipose tissue
Ruminant: TCA Cycle, FA Synthesis, Lipogenesis
Monogastric Herbivore:Glycolysis, TCA Cycle, Lipogenesis
The pancreatic enzymes important for lipid digestion are secreted as inactive zymogens, why?
Describe their activation. correct answers The Pancreas secretes inactive enzymes pro-pancreatic
lipase A2, pro-phospholipase A2, and Trypsinogen to to avoid digesting itself
Trypsinogen uses Enteropeptides to make trypsin
pro-phospholipase use trypsin to make phospholipase A2
pro-pancreatic lipase use trypsin to make pancreatic lipase
pancreatic lipase use MAG mutase to make glycerol and fatty acid
What is the lipoprotein that is made in the intestinal epithelial cell and secreted into the lymph
before entering the blood stream? What apolipoprotein best characterizes this lipoprotein? Where
does this lipoprotein enter the blood stream? correct answers Chylomicron: Apolipoprotein B48
+ TAGs