Biochem Glycogen Metabolism

Front 1

____ (3) poor in mitochondria, therefore use glucose as main source

Back 1

kidney medulla

Lens, cornea of eye

Testes

Front 2

Gluconeogenisis occurs in the _____ (2)

Back 2

liver

kidney cortex

Front 3

Short term fasting (up to 24 hours) ____ occurs

Back 3

degradation of liver glycogen

Front 4

Long term fasting (over 24 hours) ____ occurs

Back 4

gluconeogenisis mainly by liver (partly by kidney)

Front 5

Glycogen in muscle are mainly used for ____. Glycogen degradation and glycolysis are induced _____ to produce ATP

Back 5

energy

at the same time

Front 6

Muscle does not provide glucose for the ____ because it does not have the ____ to convert _____ to glucose

Back 6

blood stream

enzyme

glucose-6-P

Front 7

In liver, when glycogen degradation is _____ during fasting, glycolysis is generally _____

Back 7

activated

inhibited

Front 8

Embryo receives glucose from mothers blood and during the last 10 weeks, the baby builds _____. If mother is malnourished during last part of pregnancy, the baby will be severely _____

Back 8

glycogen stores

hypoglycemic

Front 9

Glycogen is stored as particles in the ____. The center of the particles contain _______, which bind glycogen covalently through ____ residues

Back 9

cytoplasm

glycogenin

tyrosine

Front 10

Glycogen is a _____ polymer and is ____ to be more efficient

Back 10

alpha-D-glucose

branched

Front 11

Most glucose in glycogen is linked by a ____ bonds. branches are linked by ____ bonds. Branches occur every ____ glucose molecules

Back 11

alpha(1-4) glycosidic

alpha(1-6) glycosidic

8-10th

Front 12

True/false - glycogen synthesis and degradation is reversible

True/false - glycogen synthesis and degradation can occur at the same time

Back 12

false

false

Front 13

Monosaccharides have to be _____ activated in order to build oligo- or polysaccharides

Glucose 1-phosphate + UTP -> ?

Back 13

nucleotide

UDP - glucose (catalyzed by UDP-glucose-phosphorylase)

Front 14

Glucose chain elongation is catalyzed by _____. When chain is long enough, _____ cleaves off 6-8 glucosyl residues and transfers them to another site make a ____ linkage

Back 14

Glycogen synthase

branching enzymes (4:6 transferase)

alpha (1-6)

Front 15

Glycogen degradation:

Minor route: in the ____ by ____

Major route: in the ____ by ____

Back 15

lysosome - acid alpha-glucosidase

cytoplasm - glycogen phosphorylase

Front 16

Glycogen degradation in cytoplasm uses ____ and cleaves glucose, making _____, until tetrasaccharide branches are left (4 glucose molecules), called ____. _______ enzyme transfers the trisaccharide from the tetrasaccharide to the end of another chain forming a ____ bond. The remaining glucose is ____ and released as a _____

Back 16

glycogen phosphorylase

glucose 1-P

limit dextrin

Debranching

alpha (1-4)

hydrolyzed

free glucose

Front 17

Glucose 1-P is converted to Glucose 6-P by _____

Back 17

phosphoglucomutase

Front 18

Glucose 6-P in muscle is used to _____

Back 18

produce energy

Front 19

Glucose 6-P in liver can be converted to ____. Glucose 6-P is transferred to ER by _____, then it is converted to glucose by ____. Glucose is transported out of ER to cytoplasm by _____ and is then transported from cell into circulation by ______

Back 19

glucose

glucose 6-P translocase

glucose 6-phosphatase

GLUT 7

GLUT 2

Front 20

Type Ia and b disease (1a is Von Gierke)

Deficient enzyme: (2)

organ involved: (2)

Blood metabolites

Back 20

glucose 6-phospatase
glucose 6-translocase

Hepatomegaly (liver)
renomegaly (kidney)

increase lactic acid, uric acid, lipids, decrease glucose during fasting

*causes growth retardation and delayed puberty

Front 21

Pompe disease: Type II

Deficient enzyme: (1)

organs involved: (1)

Blood Metabolites:

Back 21

acid alpha-glucosidase (lysosomal)

Cardiomegaly

Normal blood glucose

*general weak muscle tone

Front 22

McArdle Syndrome: Type V (skeletal muscle)

Deficient enzyme: (1)

Organ involved: (1)

Blood metabolites:

Back 22

glycogen phosphorylase

cramping of skeletal muscles

increased myoglobin/no increase in lactate after exercise

temporary weakness after exercise

Front 23

When in high energy state or high amounts of glucose (substrate), glycogen degradation is _____

Back 23

inhibited

Front 24

Increase in ___ and ___ causes glycogen degradation in skeletal muscle (by allosteric response). While increase in _____ and ____ inhibits glycogen degradation

Back 24

calcium - AMP

glucose 6-P - ATP

Front 25

Increase in ____ and ___ and ___ inhibits glucose degradation in liver

Back 25

Glucose - glucose 6-P - ATP

Front 26

Enzymes in liver cells: ___ when fasting, ___ when well-fed, and ____

Back 26

glucagon (phosphorylation)

insulin (dephosphorylation)

epinephrine (phosphorylation)

Front 27

Enzymes in muscle cells: ___ when well fed, and ____. No big change when fasting

Back 27

insulin (dephosphorylation)

epinephrine (phosphorylation)

Front 28

Phosphorylation of both glcogen phosphorylase and glycogen synthase pushes towards ______

Back 28

degradation of glucogen

Front 29

Insulin dephosphorylates ______ to try to synthesize glucogen

Back 29

protein phosphatase

Front 30

Glucagon and epinephrine phosphorylate _____ and ____ to induce glycogen breakdown to ____

Back 30

phosphorylase kinase - protein kinase A

Glucose 1-P

Front 31

Glucagon acts through ____ and activates ____ and _____. Protein kinase A phosphorylates _____ (active) and _____ (inactive). Phosphorylase kinase phosphorylates ____ (active). Glycogen is degraded

Back 31

G-protein-linked receptor

adenylyl cyclase - protein kinase A

phosphorylase kinase - glycogen synthase

glycogen phosphorylase

Front 32

Epinephrine stimulates glycogen degradation and acts through 2 receptors:

Back 32

Beta1-adrenergic receptor: same mechanism as for glucagon

Alpha1-adrenergic receptor

Front 33

One of the receptors epinephrine acts through is alpha 1-adrenergic receptor, which is a G-linked receptor that activates _____, which induces ______, including ___, which then induces _____

Back 33

phospholipase-Cbeta

second messengers - Ca2+

glycogen breakdown

Front 34

____ is the activator of calmodulin-dependent protein kinase and phosphorylase kinase. These enzymes activate _____

Back 34

Ca2+-calmodulin

glycogen phosphorylase (degradation)

Front 35

Insulin acts through ____ pathway, which activates _____, which dephosphorylates ____ (inactive) and _____ (active). Insulin can also activate _____ which destorys _____

Back 35

tyrosine kinase

protein phosphatases

glycogen phosphorylase - glycogen synthase

phosphodiesterase

cAMP

Front 36

Muscle glycogen phosphorylase vs liver glycogen phosphorylase. Muscle glycogen phosphorylase is _____ activated by ____. Glucose is not an allosteric inhibitor of muscle glycogen phosphorylase. ____ has no effect on muscle glycogen metabolism

Back 36

allosterically - AMP

Glucagon