Week 3

Question 1

Difference between GIFT and ZIFT

Answer 1

ZIFT means egg is fertilised first and then transferring zygote

Question 2

When is IVF used

Answer 2

Damaged/blocked fallopian tubes
Older women

Question 3

Stages of IVF

Answer 3

1. Ovarian stimulation ( FSH+ hCg, guided transvagunal follicle aspiration)
2. Sperm preparation
3. Fertilisation
4. Embryo culture
   5.embryo transfer( trans cervical )
5. Pregnancy

Question 4

Intracytoplasmic Sperm Injeftiin

Answer 4

Performed as part of IVF
single spent being injected into egg
Sperm can be surgically extracted from testis

Question 5

How does valve stenosis lead to heart failure

Answer 5

Calcification of valves makes them stiff so leak
Leaky valves mean backflow of blood and extra pressure on heart
Extra pressure on the heart increases workload and leads to failure

Question 7

How does heart muscle beat

Answer 7

Cardiac myocytes are electrically coupled with intercalated discs between adjacent cells so contract in unison

Question 8

Where is the SAN

Answer 8

within wall of RA near point of entry of superior vena cava

Question 9

Describe how a heart beat travels from SAN to rest of heart

Answer 9

SAN initiates signal
Electrical impulses spread through atrial walls that contract in unison
Impulses pass to AV node
Impulses delayed
Purkinje fibres conduct signal to contract through ventricle walls

Question 10

Why are impulses delayed from AV node to purkinje fibres

Answer 10

To ensure atria fully contract and empty fully before ventricles contract

Question 11

What factors affect pacemaker activity of SAN

Answer 11

• body temp ( high temp -> increase hr)
• positive chronotropic factors increase hr(adrenaline)
• negative chronotropic factors decrease hr( b- adrenergic)