Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Kaplan: Biochemistry Part I > Chapter 17: Amino Acids (continued) > Flashcards

Chapter 17: Amino Acids (continued) Flashcards

(77 cards)

Start Studying
1
Q

Draw out a diagram for folate metabolism.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Vitamin B12 is reduced and activated in the body to what 2 forms?

A
  1. adenosylcobalamin (used by methylmalonyl-CoA mutase)
  2. methylcobalamin (formed from N5-methyl-THF in the N- methyl THF homocysteine methyltransferase reaction)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The full name for D. latum?

A

Diphyllobothrium latum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is D. latum?

A

a parasite found in raw fish (excess B12 is stored in the body, so deficiencies develop slowly)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What would happen to symptoms of cobalamin deficiency if you gave folate?

A

It would correct the megaloblastic anemia but does not halt the neuropathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does deficiency of Vit. B12 affect the CNS specifically?

A

causes demyelination of the posterior columns and lateral corticospinal tracts in the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are some symptoms of folate deficiency?

A

megaloblastic anemia

  • macrocytic anemia
  • MCV > 100 femtoliters (fL)
  • PMN nucleus more than 5 lobes

Homocysteinemia with risk for cardiovascular disease

  • NTD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are some causes of folate deficiency?

A
  • pregnancy (NTD)
  • alcoholism
  • severe malnutrition
  • gastric or terminal ileum resection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some of the symptoms of Vit B12 deficiency?

A

macrocytic anemia
MCV > 100 femtoliters (fL)
PMN nucleus more than 5 lobes

Homocysteinemia with risk for CVS disease

methylmalonic aciduria

progressive peripheral neuropathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Compare the time it takes for folate deficiency and B12 deficiency to be evident?

A

3-4 months folate while B12 deficiency normally takes years to develop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some specialized products that tyrosine can make?

A
  • thyroid hormones T3 and T4
  • melanin
  • catecholamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are some specialized products in the body that tryptophan can make?

A

serotonin and NAD NADP (niacin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some specialized products that arginine can make?

A

Nitric oxide (NO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some specialized products that glutamate can make?

A

y-aminobutyric acid (GABA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are some specialized products histidine can make?

A

histamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Draw out the pathway for catecholamine synthesis.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name some products in the body in which heme proteins are included?

A

hemoglobin
myoglobin
all the cytochromes (ETC)
cytochrome P-450, cytochrome b5

the enzymes catalase, peroxidase, and the soluble guanylate cyclase stimulated by NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the rate-limiting enzyme for heme synthesis?

A

δ-aminolevulinate synthase (ALA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Are compounds with an “ogen” at the end of their name colorless or colorful?

A

Compounds such as urobilinogen, are colorless

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are compounds with the suffix such as urobilin colorful or colorless?

A

colorful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does a compound like urobilinogen change to urobilin and get color?

A

In the presence of O2, they spontaneously oxidized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Draw out the pathway for heme synthesis.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are some symptoms of acute intermittent porphyria? What would increase on labs?

A
  • episodic, variable expression
  • anxiety, confusion, paranoia
  • acute abdominal pain
  • port-wine urine in some patients
  • paralysis
  • motor sensory or autonomic neuropathy
  • weakness
  • excretion of ALA (d-aminolevulinic) and PBG (porphobilinogen) during episodes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a drug you can never give individuals with acute intermittent porphyria?

A

never give barbituates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are some symptoms of porphyria cutanea tarda?
* most common porphyria * photosensitivity * inflammation, blistering, shearing of skin in areas exposed to sunlight * hyperpigmentation * exacerbated by alcohol * red-brown to deep-red urine (tea colored urine)
26
What are other names for acute intermittent porphyria?
- porphobilinogen deaminase deficiency - hydroxymethylbilane synthase deficiency
27
Inheritance pattern of acute intermittent porphyria?
AD
28
When, in a humans life, will acute intermittent porphyria typically appear?
late onset
29
T/F. Some of the individuals suffering with acute intermittent porphyria are incorrectly diagnosed and placed in psychiatric institutions.
True
30
Do individuals with acute intermittent porphyria have photosensitivity?
no
31
Porphyria cutanea tarda results because of a deficiency of what enzyme?
deficiency of uroporphyrinogen decarboxylase
32
What are substances that can exacerbate porphyria cutanea tarda?
hepatotoxic substances, such as excessive alcohol or iron deposits
33
What are the skin lesions in porphyria cutanea tarda caused by?
related to high circulating levels of porphyrins
34
What drug is associated with B6 deficiency?
deficiency of pyridoxine is associated with isoniazid therapy for tuberculosis
35
What is the enzyme that introduces the iron into the heme ring?
ferrochelatase introduces Fe2+ into the heme ring
36
Give the MOA by which barbiturates can exacerbate prophyrias?
barbiturates are hydroxylated by microsomal cytochrome P-450 system in the liver to facilitate their efficient elimination from the body. Administration of the barbiturates results in stimulation of cytochrome P-450 synthesis, which in turn reduces heme levels. Reduction in heme lessens the repression of ALA synthase, causing more porphyrin precursor synthesis. The indirect production of more precursors by barbiturates exacerbates the disease
37
What are some enzymes that that lead inactivates?
many including ALA dehydratase and ferrochelatase (heme synthase)
38
Another name for ferrochelatase.
heme synthase
39
What are some symptoms of lead poisoning?
* coarse basophilic stippling of erythrocytes * headache, nausea, memory loss * abdominal pain, diarrhea (lead colic) * lead lines in gums * lead deposits in abdomen and epiphysis of bone seen on radiography * neuropathy (claw hand, wrist-drop) * increased urinary ALA * increased free erythrocyte protoporphyrin
40
MOA of your body creating zinc-protoporphyrin?
failure of ferrochelatase to insert Fe2+ into protoporphyrin IX to form heme, such as in lead poisoning or iron deficiency anemia, results in the nonenyzymatic insertion of Zn2+ to form zinc-protoporphyrin
41
What is an important property of zinc protoporphyrin?
This complex is extremely fluorescent and easily detected
42
What is the inheritance pattern of hemochromatosis?
AR
43
How is hemochromatosis caused?
when there is a daily intestinal absorption of 2-3 mg of iron compared with the normal 1 mg because of a hepcidin mutation over several years then this condition occurs
44
Ferritin binds what type of iron?
Fe3+ ferric iron
45
Fe2+ is what type of iron?
ferrous iron
46
Which type of anemia can cause coarse basophilic stippling in the erythrocyte?
lead poisoning
47
What type of anemia is caused by pyridoxine deficiency? (macrocytic, normocytic, or microcytic?)
mirocytic
48
Which type of anemia is caused by iron deficiency anemia?(macrocytic, normocytic, or microcytic?)
microcytic
49
Which type of anemia is caused by lead poisoning? (macrocytic, normocytic, or microcytic?)
microcytic
50
Which type of anemia will cause ringed sideroblasts in bone marrow to be seen?
lead poisoning
51
Describe protoporphyrin levels in Vit. B6 deficiency, iron deficiency, and lead poisoning.
B6 Protoporphyrin: decreased Iron def: Protoporphyrin: increased Lead poisoning Protoporphyrin: increased
52
Describe d-ALA levels in vitamin B6 deficiency, iron def., and lead poisoning.
B6 def ferritin: decreased Iron deficiency: normal lead poisoning: increased
53
Describe serum iron in B6 def, iron def, and lead poisoning.
B6 serum iron: increased Iron deficiency serum iron: decreased Lead poisoning serum iron: increased
54
What are some ways in which one can get lead poisoning?
lead paint, pottery glaze, batteries
55
How would you diagnose if one has lead poisoning?
by measuring blood lead levels
56
What is another name for ferroxidase?
aka ceruloplasmin
57
What is ceruloplasmin?
a Cu2+ protein enzyme that oxidizes Fe2+ to Fe3+ for transport and storage
58
How do we lose ferritin from the body?
by bleeding and shedding epithelial cells of the mucosa and skin
59
What binds excess Fe3+ to prevent escape of free Fe3+ into the blood?
hemosiderin
60
Be able to draw out a diagram for iron metabolism.
refer to diagram
61
How do hepatocytes make bilirubin water soluble?
they conjugate it to glucuronic acid
62
What converts conjugated biilrubin to urobilinogen?
intestinal bacteria
63
Bile duct obstruction can lead to what colored stools?
clay colored
64
What causes the red-brown color of feces?
urobilinogen being further converted to bile pigments (stercobilin) and excreted in the feces
65
AT , very high levels, how can bilirubin lead to kernicterus?
bilirubin may cross the blood brain barrier and precipitate in the basal ganglia, causing irreversible brain damage
66
Be able to create a diagram on heme catabolism and bilirubin.
Refer to diagram.
67
Another name for UCB?
unconjugated bilirubin (indirect bilirubin)
68
Another name for conjugated bilirubin?
direct bilirubin
69
What are some examples of hemolytic crisis developing and causing jaundice and kernicterus.
episode of hemoylysis in G6PDH deficiency Sickle cell crisis Rh disease of the newborn
70
Crigler Najjar syndrome Type I pathology?
Absent UDP - glucuronyltransferase
71
Crigler Najjar syndrome Type II pathology?
Deficiency of UDP-glucruonyltransferase enzyme but not absence like Type I
72
Gilbert syndrome pathology
Deficiency of UDP - glucuronyltransferase but to a much lesser extent than Crigler Najjar Type II. Usually jaundice is brought about by triggers (stress, alcohol, fasting/starvation)
73
How does phyisologic jaundice of the newborn occur?
becuase the enzyme glucuronyl transferase may not be fully induced
74
Viral hepatitis or cirrhosis produces an increase in which type of bilirubin? (direct or indirect)
both direct and indirect
75
Which is higher in alcoholic liver disease AST or ALT?
AST increases more than ALT
76
Which is higher in viral hep ALT or AST?
ALT increase more than AST
77
What is the color of feces if conjugated bilirubin increases in the blood?
feces are light colored or clay colored. Because its a increased because of bile duct obstruction.

Kaplan: Biochemistry Part I (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions