test 3 baldini

Question 1

What are the blood group antigens composed of?

Answer 1

A Ceramide (sphingosine with fatty acid)
no antigen for type O
add Galactosamine= type A
add galactose = type B

Question 2

Spur cell anemia

Answer 2

Uncommon hemolytic anemia where increased cholesterol results in rigid “spur” red blood cells which spleen destroys

Question 3

What’s a liposome?

Answer 3

When a lipid drops in water it forms a sphere with a polar surface on the outside and inside of the sphere. Drugs, enzymes, and DNA can be packaged on the inside

Question 4

how does glucagon/epinephrine cause glycogen breakdown?

Answer 4

1. Activates adenylate cyclase to release cAMP
2. cAMP activates protein kinase A
3. PKA phosphorylates/activates glycogen phosphorylase kinase
4. Glycogen phosphorylase kinase phosphorylates glycogen phosphorylase to activate it to then breakdown glycogen
   (calcium promotes activation of phosphorylase kinase)

Question 5

how does insulin stimulate glycogen synthesis?

Answer 5

It stops the breakdown and stimulates synthesis
1. Insulin activates a receptor tyrosine kinase
2. This activates phosphoprotein phosphatase (phosphatases remove phosphate)
3. Dephosphorylates glycogen synthase to activate it

stops breakdown: Phosphoprotein phosphatase also removes the phosphate from glycogen phosphorylase kinase and glycogen phosphorylase to stop glycogen breakdown

Question 6

what is Von Gierke disease? Type I GSD

Answer 6

deficient in Glucose-6-phosphate
severe hypoglycemia, blood lactidosis, blood uric acidosis, hepatomegaly

Question 7

Pompe disease? Type II GSD

Answer 7

1,4-glucosidase deficiency
“Pompe trashes the pump”
cardiomyopathy, hypotonia, enlarged tongue
infant death due to cardiac failure

Question 8

Cori disease? Type III GSD

Answer 8

debranching enzyme deficiency
milder von gierke
“AB - CD”

Question 9

Andersen disease? Type IV GSD

Answer 9

Branching enzyme deficiency
death from liver cirrhosis due to glycogen accumulation
failure to thrive in infants
“AB-CD”

Question 10

McArdle disease? Type V GSD

Answer 10

Skeletal muscle glycogen phosphorylase deficiency
muscle cramps and pain on exertion, easily fatigued
normal life expectancy

Question 11

what is type 1a CDG

Answer 11

Phospomannose mutase 2 deficiency
cannot convert mannose 6-P into mannose 1-P
presents with seizures, hypotonia, microcephaly, stroke-like episodes
Test by detecting underglycosylated serum transferrin

Question 12

What is type 1b CDG

Answer 12

Deficiency in phophomannose isomerase
cannot convert mannose 6-P into fructose 6-P
presents with seizures, hypotonia, microcephaly, stroke-like episodes
Test by detecting underglycosylated serum transferrin

Question 13

Hereditary fructose intolerance

Answer 13

deficiency in Aldolase B
fructose and ATP is “trapped” in liver due to fructose 1-phosphate not being able to convert
hypoglycemia and liver damage

Question 14

what is GALT

Answer 14

deficiency in galactose 1-P uridyltransferase and cannot form UDP-galactose to eventually become glucose
Classic severe form with severe retardation if not treated, cataracts

Question 15

UDP-glucose-4-epimerase deficiency?

Answer 15

similar to GALT if present in all cells, but ok if just red blood cells
cataracts and retardation if not treated

Question 16

what is Crigler-Najjar syndrome?

Answer 16

deficiency in UDP-glucoronyltransferase
cannot conjugate bilirubin to excrete it in bile and instead transfers to lipids resulting in kenicturus (brain damage)
normally takes a few weeks to activate in newborns

Question 17

what is surfactant made of and why is it important?

Answer 17

AKA lecithin- a phosphatidyl choline with two fatty acids made of palmitoyl groups
Decreases surface tension of the fluid layer to prevent atelectasis (lung collapsing due to “sticking together” at end of exhaling)
deficiency results in respiratory distress syndrome, which can also occur in adults whose type II cells (secretes surfactant) are destroyed from chemo

Question 18

where does sphingolipid breakdown occur?

Answer 18

in the lysosomes

Question 19

What is Tay-Sachs disease?

Answer 19

deficiency in hexosaminidase A
cherry-red spot, with NO hepatosplenomegaly, neurodegeneration
GM2 ganglioside accumulates

Question 20

Neimann-Pick disease?

Answer 20

Deficient in Sphingomyelinase
“sphinger picks nose”
cherry-red spot, WITH hepatosplenomegaly, neurodegeneration
sphingomyelin accumulates

Question 21

Gaucher disease?

Answer 21

deficiency in glucocerebrosidase
hepatosplenomegaly, anemia, thrombocytopenia, Gaucher cells

Question 22

Fabry disease?

Answer 22

deficiency in alpha-galactosidase A- X linked
“fabry is fabulous” affects the skin
angiokeratomas, lack of sweat, renal disease
ceramide trihexoside accumulates

Question 23

Fatty acid synthesis step 1?

Answer 23

Committed step
Acetyl-CoA carboxylase with biotin (B7) attached
converts Acetyl-CoA using HCO3+ATP into
Malonyl-CoA

Question 24

Fatty acid synthesis step 2?

Answer 24

Malonyl-CoA donates carbons to form fatty acids such as Palmitic Acid (requires 8 Acetyl-CoA)
fatty acid synthesis requires a bunch of NADPH

Question 25

Acetyl-CoA carboxylase (ACC) regulation

Answer 25

Active when dephosphorylated
inactive when phosphorylated
Activation: insulin (hormonal) and citrate (allosteric)
deactivation glucacon/epinephrin (hormonal) long chain fatty acids like palmitoyl (allosteric)

Question 26

Type II diabetes effect on GLUT4

Answer 26

Elevated free fatty acids promoted insulin resistance by decreasing the response of GLUT4 so that it does not move to cell surfaces. Eventual overproduction of insulin can “burn out” pancreatic beta-cells

Question 27

Acetyl-CoA carboxylase (ACC) regulation

Answer 27

Active when dephosphorylated
inactive when phosphorylated
Activation: insulin (hormonal) and citrate (allosteric)
deactivation glucagon/epinephrin (hormonal) long chain fatty acids like palmitoyl (allosteric)

Question 28

Steps of fatty acid oxidation?

Answer 28

1. acyl-CoA synthetases activate fatty acids by converting to acyl-CoA
2. Carnitine shuttle transports fatty acyl-CoA into mitochondrium
3. beta-oxidation of fatty acids in the matrix

Question 29

what is omega oxidation?

Answer 29

a small component of fatty acid oxidation that occurs in ER that forms decarboxylic acids that are present in urine
Primary pathway if beta oxidation is inhibited

Question 30

what are ketone bodies and their use?

Answer 30

3 substances formed from acetyl-CoA
: acetoacetate, beta-hydroxybutyrate, and acetone
fasting increases levels to supply brain and muscles

Question 31

what does an error in beta-oxidation lead to?

Answer 31

decreases Acetyl-CoA generation
Reduced gluconeogenesis in liver, increased glucose consumption in muscle
Hypoketosis and Dicarboxylic aciduria due to increased omega-oxidation

Question 32

Primary Carnitine deficiency

Answer 32

defect of plasma membrane carnitine transporter “on the outside”
affects muscle, heart, and kidney
low amount of carnitine in the blood

Question 33

Secondary carnitine deficiency

Answer 33

Carnitine palmitoyl transferases deficiency “on inside”
not a deficiency of carnitine but the carnitine is lost in the urine also
MCAD is a type of secondary

Question 34

Cortisol release

Answer 34

1. hypothalamus releases CRH (corticotropin releasing hormone)
2. CRH causes anterior pituitary to release ACTH (adrenocorticotropic hormone)
3. Adrenal cortex releases corticosteroids which causes Na absorption, epinephrine secretion, and gluconeogenesis

Question 35

T3 and T4 release

Answer 35

1. Hypothalamus releases TRH (thyrotropin-releasing hormone)
2. TRH causes the anterior pituitary to release TSH (thyrotropin)
3. TSH causes the thyroid to release T4/T3 which increases metabolism

Question 36

Vasopressin effects and what is a defect called?

Answer 36

also called ADH (antidiuretic hormone)
when blood pressure falls or if Na levels are high, ADH is released to increase aquaporins in the kidneys to dilute blood and increase BP
Diabetes insipidus when defective- results in thirst and lots of piss. Caused by defect of pituitary or Kidneys

Question 37

What does renin and aldosterone do?

Answer 37

when blood volume is low renin is released
Renin is converted to angiotensin by ACE
causes smooth muscle contraction and increased water reabsorption