Ovulation To Implantation

Question 1

Which part of the brain are sexual cycles in a female controlled by?

Answer 1

The Hypothalamus

Question 2

What hormone does the hypothalamus release that acts on the anterior lobe of the pituitary gland?

Answer 2

Gonadotrophin-releasing hormone (GnRH)

Question 3

What are the two gonadotropins?

Answer 3

Follicle-stimulating hormone (FSH) and Luteinizing hormone (LH)

Question 4

How many follicles grow under the influence of what at the beginning of each ovarian cycle?

Answer 4

15-20 under the influence of FSH

Question 5

Importance of FSH on growing follicles?

Answer 5

Without the presence of this hormone the primary follicles would die and become atretic.

Question 6

What is the corpus atreticum?

Answer 6

Connective tissue replacing degenerated atretic follicle

Question 7

Purpose of growth differentiation factor 9

Answer 7

Proliferation of follicular (granulosa) cells

Question 8

Which parts of the oocyte produce estrogen and how?

Answer 8

Theca interna and granulosa cells; theca interna produce androstenedione and testosterone while the granulosa cells convert them to estrone and 17 b-estradiol

Question 9

What happens as a result of a surge in estrogen production?

Answer 9

-The underline endometrium enters the proliferative stage
-Thinning of cervical mucus
-Anterior lobe of pituitary secretes LH

Question 10

What occurs when there is a surge in LH at the mid cycle?

Answer 10

-Elevated concentrations of maturation promoting factor;oocytes complete meiosis 1 and start meiosis 2
-Production of progesterone by follicular stromatolites cells (luteinization)
-Causes follicular rupture and ovulation

Question 11

What stage of meiosis is the oocyte arrested in approx 3 hours before ovulation?

Answer 11

Metaphase 2