Integrated PBL

Question 1

What enzyme is deficient in PKU?

Answer 1

Phenylalanine hydroxylase

Question 2

What is phenylalanine normally converted to by PAH?

Answer 2

Tyrosine

Question 3

Tyrosine is important in the synthesis of which compounds?

Answer 3

Dopamine, noradrenaline, adrenaline, thyrxoine, melanin

Question 4

What does high levels of Phe cause?

Answer 4

Saturation of the large neutral amino acid transporter at the BBB
This means other important amino acids cannot reach the brain and therefore causes brain development probelms

Question 5

What accumulates with increase Phe levels due to side reactions?

Answer 5

Phenylpyruvate

Phenylethylamine

Question 6

Symptoms of PKU

Answer 6

Microcephaly 
Developmental delay
Eczema
Hyperactivity 
Mental retardation 
Reduced melanin in skin

Question 7

Diagnosis of PKU

Answer 7

Heel prick test done 2-5 days after birth

Detects levels of Phe

Question 8

Treatment of PKU

Answer 8

Diet that limits Phe intake

Low in soybeans, sea meat, egg whites, shrimps, chicken breast, watercress, fish, nuts, lobster, tuna, turkey

Question 9

Inheritance pattern of PKU

Answer 9

Autosomal recessive

Question 10

PAH gene location

Answer 10

12q22-24.1

Question 11

Importance on monitoring Phe levels in pregnancy

Answer 11

Must stay within the healthy range to avoid teratogenic effects on baby
Foetus’ liver will begin to produce PAH causing Phe levels to drop
Mother may have to start eating more Phe to avoid low levels

Question 12

Symptoms of low Phe

Answer 12

Headaches, nausea, general malaise

Question 13

Cardiovascular changes in exercise

Answer 13

Increase in HR by 25%
50% in peripheral vascular resistance
Fall in blood pressure with low at 17-24 weeks

Question 14

Change in haematocrit in pregnancy

Answer 14

Large increase in plasma volume in first trimeter
RBC increase later but not to the same degree as plasma
Heamodiluation –> physiological anaemia of pregnancy

Question 15

Why do people suffer with tachycardia and palpitations in anaemia?

Answer 15

Blood carrying less oxygen per unit measure
More blood flow required to get the same amount of oxygen
Heart must pump faster to deliver this oxygen
Palpitations more likely

Question 16

ACL

Answer 16

Anterior medial tibia to posterior lateral femur
Prevents forward movement of the tibia
Stabilises knee in extension
Prevents hyperextension and internal rotation

Question 17

PCL

Answer 17

Posterior lateral tibia to anterior medial femur
Prevents backward movement of the tibia
Stabilises knee in flexion
Prevents hyperflexion and external rotation

Question 18

Causes of microcytic anaemia

Answer 18

Iron deficiency

Thalassaemias

Question 19

Causes of normacytic anaemia

Answer 19

Acute blood less
Leukaemia 
Chronic disease
Sickle cell anaemia
Renal failure

Question 20

Causes of macrocytic anaemia

Answer 20

B12/folate deficiency

Liver disease

Question 21

Ferritin

Answer 21

Ubiquitous IC protein that can store and release iron

When not bound to iron the protein is called apoferritin

Question 22

Symptoms of anaemia

Answer 22

Tiredness
Feeling faint
Shortness of breath
Palpitations

Question 23

Folic acid is which B group vitamin?

Answer 23

B9

Question 24

How much folic acid should be taken before and during pregnancy?

Answer 24

400mg

Question 25

What does folic acid help to prevent?

Answer 25

Neural tube defects
Anencephaly - failure of anterior neuropore to close
Spina bfida - failure of posterior neuropore to close

Question 26

Foods rich in folate

Answer 26

Green leafy vegetables
Brown rice
Granary bread