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Flashcards in Other Deck (16):

The umbilical artery arises from? (In the fetus)

The internal iliac artery


The umbilical vein goes into?

Through liver via the ductus venosus into the IVC


What is the function of the bulbourethral gland?

Lubricates male tract
Clears out left over urine


What are the 4 main methods of contraception?

Prevent implantation
Prevent fertilisation
Stop sperm production
Stop ovulation


What are the four main steps of fertilisation?

Survive the vagina
Penetrate the cervix
Swim to the Fallopian tubes


What part of ejaculate keeps the pH basic?

Seminal fluid


What helps the sperm swim through the cervix?

Oestrogen relaxes the muscles of the cervix and makes mucus more fluid
Progesterone makes mucus thicker making it harder for sperm to penetrate


Explain capacitation of the sperm

Proteins are stripped from the plasma membrane of the sperm
This expresses receptors for chemoattractants
Stripping of cholesterol from the plasma membrane allows influx of Ca
This triggers hyperactivation


Which chemical messengers attract sperm to the correct place?

Progesterone from corona radiata cells
Atrial natriuretic peptide from follicular fluid


Explain how sperm penetrates the oocyte

Sperm binds to ZP
influx of Ca in sperm triggers exocytosis of acrosome which contains hydrolytic enzymes
These enzymes dissolve ZP
Whip like action pushes sperm forwards
Membranes fuse and contents enters into oocyte

A rise in Ca in oocyte causes release of granules that make ZP harder
The rise in Ca causes second meiotic division
Male and female pronuclei fuse


Which hormones and how do they prepare the endometrium for implantation?

Oestrogen causes proliferation of endometrium
Progesterone maintains and thickens lining


What is involution? And what is it due to?

Dramatic shrinkage of the uterus
Due to the disappearance of oestrogen and progesterone


What are the two main theories for the onset of labour?



Which hormones inhibit milk production in pregnancy?

Progesterone and oestrogen


What are the anatomical changes of the breast in pregnancy?

First half of pregnancy, ducts branch and extend, the lobes and alveoli proliferate and expand
The third trimester, cells double in size, epithelial cells convert to lactocytes


What are the effects of prolactin and oxytocin on breast feeding?

Prolactin causes milk production
Oxytocin cases smooth muscle contraction to allow milk ejection