Physiology Of Labour

Question 1

…. stimulate gab junctions formation and Under the influence of them, and other humoral mediators, there is an increase in proteolytic activity and a reduction in collagen and elastin

Answer 1

Prostaglandins

Question 2

What bring about a proinflammatory change
with a significant invasion by neutrophils?

Answer 2

Interleukins

Question 3

Dermatan sulphate is replaced by the more hydrophilic ….. , which results in an increase in water content of the cervix. causes cervical softening or ‘ripening’, so that contractions, when they begin, can bring about the processes of effacement and dilatation

Answer 3

hyaluronic acid

Question 4

maintains uterine relaxation by suppressing prostaglandin production, inhibiting communication between myometrial cells and preventing oxytocin release

Answer 4

Progesterone

Question 5

Prostaglandin synthesis by the ……. is enhanced, leading to an increase in calcium influx into the myometrial cells

Answer 5

chorion and the decidua

Question 6

The production of ……. by the placenta increases in concentration towards term and potentiates the action of prostaglandins and oxytocin on myometrial contractility

Answer 6

corticotrophin-releasing hormone (CRH)

Question 7

As labor becomes established, the output of oxytocin increases through the ….. reflex
Which means Pressure from the fetal presenting part against the cervix is relayed via a reflex arc involving the spinal cord and results in increased oxytocin release from the maternal posterior pituitary

Answer 7

Fergusson reflex

Question 8

Myometrial cells of the uterus contain filaments of actin and myosin, which interact and bring about contractions in response to

Answer 8

an increase in intracellular calcium

Question 9

Actin–myosin interaction occurs along the full length of the filaments so that a degree of shortening occurs with each successive interaction. This progressive shortening of the uterine smooth muscle cells is called ….. and occurs in the cells of the ……

Answer 9

retraction, upper part of the uterus

Question 10

….. and …. increase intracellular free calcium ions, whereas ….. compounds and ….. do the opposite

Answer 10

Prostaglandins & oxytocin
Beta-adrenergic & calcium-channel blockers

Question 11

Interactions between …. & …. & …. during the earlier stages of pregnancy keep the cervix firm and closed

Answer 11

collagen, fibronectin and dermatan sulphate (a proteoglycan)