23 Ketone Bodies, Complex Lipids, Adipose tissue Hormones Flashcards Preview

Biochemistry Unit 3 > 23 Ketone Bodies, Complex Lipids, Adipose tissue Hormones > Flashcards

Flashcards in 23 Ketone Bodies, Complex Lipids, Adipose tissue Hormones Deck (28):
1

In what tissue and organelle are ketone bodies made?

ketone bodies are made in the mitochondrial matrix of cells in the liver

2

What kind of conditions favor ketogenesis in liver cells?

ketone body synthesis is stimulated under these conditions: fasting, starving, high fat/low carb diet, heavy alcohol consumption, and diabetes

3

Which tissues use ketone bodies as fuel?

all tissues use it, except for 2

4

Which tissues do not use ketone bodies as fuel and why not?

Liver, it lacks enzyme, succinyl CoA: acetate transferase and Red blood cells, which do not have mitochondria, the site of ketone body synthesis

5

ketone body synthesis regulation

TBC

6

What are examples of the physiological functions of glycerophospholipids?

1. main components of cellular membranes along with sphingomyelin 2. make up lipoproteins, bile, lung surfactant 3. sources of polyunsaturated fatty acids, like Arachidonic Acid, leads to eicosanoid production

7

Phosphatidic acid is necessary for glycerophospholipid synthesis, so how is it produced?

it is made from glycerol-3-phosphate and 2 fatty acyl CoAs.

8

glycerophospholipids made from diacylglycerol

phosphatidylethanolamine,
phosphatidylcholine,
phosphatidylserine

9

glycerophospholipids made from CDP-diacylglycerol intermediate

phosphatidylinositol
phosphatidylglycerol
cardiolipin

10

How is diacylglycerol formed from phosphatidic acid?

Phosphatidic acid loses a phosphate, by the enzyme phosphatase, to form diacylglycerol

11

examples of activated head groups
(glycerophospholipid synthesis)

CDP-ethanolamine and CDP-choline

12

example of activated backbone (glycerophospholipid synthesis)

CDP-diacylglycerol

13

role of phosphatidylglycerol

it makes cardiolipin, which is found in the inner mitochondrial membrane, and makes the membrane impermeable to small molecules

14

what is phosphatidic acid?

a key intermediate and precursor of glycerophospholipids

15

purpose of ketone bodies

ketone bodies serve as a source of fuel during fasting, starvation or a high fat diet. they are synthesized mainly in the liver mitochondria whenever fatty acids are high in the blood.

16

physiological functions of sphingolipids

are involved in intercellular communication, are antigenic determinants of ABO blood groupd, used as virus receptors, and component of myelin sheaths

17

the three classes of glycolipids, and are all made by reacting with

cerebrosides, globosides and gangliosides are all made by reacting with ceramides

18

forming cerebosides

ceramide reacts with a UDP sugar, have only one sugar attached

19

forming globosides and gangliosides

ceramide reacts with additional sugars to form globosides, and ceramide reacts with additional sugars and a sialic acid (NANA) to form a ganglioside

20

the enzyme and the substrates of glycosphingolipids

use of glycosyltransferases to add activated sugars, UDP sugars

21

how are glycosphingolipids degraded?

sphingolipids are degraded by lysosomal enzymes, they are known as acid hydrolyses, until all that is left is the ceramide

22

causes of sphingolipidoses

these are lysosomal storage diseases caused by decreased activity of lysosomal enzymes, due to the mutational defects of enzymes specifically involved in the breakdown of sphingolipids

23

defective enzyme of Tay Sachs disease, what would it normally cleave

defective enzyme is called Hexosaminidase A, it normally cleaves ganglioside GM2, but causes buildup of vacuoles in cells since they're not cleaved, leading to a disruption of normal cell function

24

adipose tissue as an endocrine gland and what hormones does it release

adipose tissue not only stores TAGs, but also secretes the hormones leptin and adiponectin to regulate fat and glucose metabolism

25

what causes leptin release

an increase in TRIGYCERIDE levels, stimulates leptin release, it signals us to stop eating by binding to leptin receptors in the brain

26

what causes adiponectin release

its secretion is reduced as adipoctyes get larger

27

Adiponectin affect on muscle metabolism

adiponectin causes a signal cascade, by binding to receptors, it activates AMPK, and a nuclear transcription factor, PPAR.
Leads to enhanced fatty acid oxidation and enhanced glucose uptake by the muscle

28

conditions present for the diagnosis metabolic syndrome, and are at increased risk for

increased waist circumference, elevated triglycerides, reduced HDL, elevated blood pressure and elevated fasting glucose, are at increased risk for Type 2 Diabetes and cardiovascular disease