Week 5 Flashcards
Biotin fxn
cofactor for carboxylation rxns
Folic acid fxn
Vitamin B9; cofactor (tetrahydrofolate) for 1 carbon transfers in biosynthesis of AAs
This vitamin is needed to prevent neural tube defects.
Vitamin B9 (folic acid)
Vitamin C
collagen formation, CT maintenance, antioxidant
Vitamin B1
Thiamine; TPP (cofactor); decarboxylation rxn
Vitamin B2
Riboflavin; active forms are FAD and FMN; redox rxns
Vitamin B3
Niacin; NAD+ and NADP+; repair UV light damage; redox rxns
Role of Vitamin B6
transamination; active form is PLP which is involved in glycogenolysis
Vitamin B12
Cobalamin; methylmalonyl CoA mutase (breakdown odd-numbered fatty acids); methionine synthesis
Vitamin B5
pantothenic acid; CoA; acyl transfer
Which vitamin is derived from Tryptophan?
Niacin (vitamin B3)
The PDH complex requires the cofactors:
TPP (thiamine), FAD+, Lipoic Acid, NAD+, and CoA
A deficiency in vitamin B6 (pyridoxine) will cause:
*abnormal AA metabolism
*2nd pellagra
*microcytic anemia
What causes deficiency in vitamin B6?
primary deficiency is rare; seen in women on OC and alcoholics
Define electrogenic.
A net charge of movement across a cell membrane.
The negative Vm potential of neurons develops bc
the non-zero membrane permeability for K+ moves Vm closer to Veq
This vitamin’s function is gamma carboxylation of glutamate residues and to activate clotting factors.
Vitamin K
This vitamin’s function is important for bone and calcium homeostasis.
Vitamin D
This vitamin’s function is important for retinols
Vitamin A
Deficiency in this vitamin causes night blindness.
Vitamin A
Deficiency in this vitamin causes rickets and osteomalacia.
Vitamin D
Without Vitamin B12 there would be a ____ in the body.
accumulation of fatty acids
A deficiency in Vitamin B12 can be caused by:
*not eating enough animal protein
*diseases of ileum (like Crohn’s disease)
*pancreatic insufficiency
*pernicious anemia
chondroitin sulfate role in the body
support for collagen and CT; deficiency leads to osteoarthritis
Dermatan sulfate role in the body
flexibility for skin, blood vessels, and heart valves
Keratan sulfate role in the body
cornea
Heparin/Heparan sulfate
anticoagulant
What are the products and substrates of the glutamate dehydrogenase rxn?
Glutamate –> alpha-keto acid + NH3
Where do the two nitrogens come from in the molecule of urea?
*Aspartate
*free NH4+ from glutamate
Which enzyme catalyzes the rate limiting step in the urea cycle?
Carbamoyl phosphate synthetase I (CPSI)
Where do the first two rxns of the urea cycle take place?
mitochondria
What is the name of the cofactor that is needed for activation of the CPSI?
N-acetylglutamate
Why is hyperammonemia deadly?
the increase in ammonia will deprive alpha ketoglutarate from the TCA cycle
Ketogenic AAs
Leucine, Lysine; can be metabolized to produce acetyl-CoA and acetoacetyl-CoA which are precursors to ketone bodies
Which AAs are both ketogenic and gluceogenic?
Phenylalanine, Isoleucine, Tyrosine, Tryptophan
What are the products of metabolism of glucogenic AAs?
fumarate, succinyl-CoA, oxaloacetate, alpha ketoglutarate, pyruvate
Which AAs enter TCA cycle as oxaloacetate?
Asparagine, Aspartate
Which enzyme is deficient in disease phenylketonuria?
phenylalanine hydroxylase; high [Phe] causes mousey odor, hypopigmentation, and CNS symptoms
Which enzyme is deficient in disease alkaptonuria?
homogenic acid oxidase; homogenic acid can be present in the urine which causes it to turn black one it touches air (oxidized)
Which enzyme is deficient in disease classic homocystinuria?
cystathionine synthase; causes high [met] and [Hcy] which can have symptoms of brittle bones and eye issues
Which enzyme is deficient in disease maple syrup urine disease?
alpha keto acid dehydrogenase
Which AAs will accumulate in maple syrup urine disease?
Isoleucine, lysine, valine
For muscle grading, what is a normal score?
5
For muscle grading, what is moves with gravity eliminated?
2
For cardiac grading, what is a normal score? and what is the range?
2+; 0-3+
What is the range for muscle grading score?
0-5
What is the grading response for a reflex with clonus?
4+ (scale is 0-4+)
Hyperkalemia will ____ the resting membrane potential.
raise (make more positive)
Catecholamines (epi/nor-epi) stimulate the ____ in the liver, _____ in skeletal muscle, and ____ in adipose tissue.
glycogenolysis, glycogenolysis, lipolysis
Type I diabetes is characterized by ______, ________ and _______.
hyperglycemia, hypertriacylglycerolemia and ketonemia
Type 2 diabetes is characterized by ______ and _____.
hyperglycemia, dyslipidemia
Which vitamin is most closely involved in the clotting cascade?
Vitamin K
What is the total energy requirement for gluconeogenesis?
4 ATP, 2 NADH, 2 GTP
Which AAs are involved in O-linked glycoproteins?
Serine, Tyrosine
Which AA is involved in N-linked glycoproteins?
Asparagine
Which nerve innervates the flexor carpi radialis m.?
median n.
Which nerve innervates the flexor carpi ulnaris?
radial n.
What type of nerve fibers are generally found in the lateral horns of the spinal cord?
sympathetic nerves
The nipple line can be found within which dermatome?
T4
Deficiency of which of the following vitamins can affect activity of the PDH complex and cause edema, cardiac failure, and/or peripheral neurologic dysfunction?
Vitamin B1 (Thiamine); TPP cofactor
What disease is caused by a deficiency of vitamin B3 (niacin)?
Pellagra
What disease is caused by a deficiency in vitamin B1 (thiamine)?
Beriberi
Aldolase converts _____ to ______.
F1,6-BP to G3P
What 3 molecules are the only 3 that are allosterically regulated in glycolysis?
hexokinase, PFK-1, pyruvate kinase
Name 3 ketone bodies.
acetoacetic acid, acetone, beta-hydroxybutyric acid
Cholesterol derived from the liver is delivered to peripheral tissues by:
LDL
Which molecule acts as the carrier to move acetyl-CoA across the mitochondrial membrane for fatty acid biosynthesis?
Citrate
How are long chain FAs moved into the mitochondria for fatty acid beta oxidation?
Carnitine Shuttle
