Gametes

Question 0

When primordial germ cells become active

Answer 0

Puberty to death

LH and Leydig cells play important role

Question 1

primordial germ cells (PGCs)

Answer 1

Where Gametes are derived from
formed in the epiblast during the second week and that move to the wall of the yolk sac (Fig. 2.1). During the fourth week, these cells begin to migrate from the yolk sac toward the developing gonads, where they arrive by the end of the fifth week

Question 2

Two types of spermatogonia

Answer 2

Self renewal- create more spermatogonial stem cells

Spermatogenesis- leads to the progeny of sperms that are all linked by cytoplasmic bridges

Question 3

Order of development of spermatogenesis

Answer 3

Spermatogonia 
                 Mitosis 
Primary spermatocyte 
                 Meiosis
Secondary spermatocyte 
                 Meiosis 
Spermatid
                 Maturation 
Mature sperm

Question 4

Spermiogeneis

Answer 4

Conversion of spermatids into mature sperm

Once complete mature sperm enter the seminiferous tubule

Question 5

Process of spermiogenesis

Answer 5

Loss of cytoplasm
Condense nucleus
Form neck and tail
Form Acrosome

Question 6

Capacitation

Answer 6

Final step in maturation of the sperm
Occurs in female reproductive tract
In response to fluids in uterine tubes involves the pruning of the sperm glycocalyx

Question 7

Oogonia maturation begins…

Answer 7

Before birth PGCs differentiate into oogonia in the female location
By end of third month they are arranged in clusters surrounded by flat epithelial cells. (Follicular cells driver from surface of epithelium covering the ovary)

Question 8

Primordial follicle

Answer 8

Capsule and follicle together are the primordial Oocyte follicular cells prevent any further progression.
Single cell layer thick

Question 9

Prevents further maturation of the Oocyte in follicle

Answer 9

Oocyte maturation inhibitor. OMI

Question 10

Primary follicle

Answer 10

Has a zona pellucida formed and several layers of cuboidal cells

Question 11

Two stages of ovarian cycle

Answer 11

Follicular FSH

Luteal phase LH

Question 12

FSH and LH cause what

Answer 12

Primordial follicles begin to thicken to cuboidal cells (primary follicles)

Question 13

Zona pellucida

Answer 13

A glycoprotein coat secreted by the follicle cells and Oocyte. Follicle cells then differentiate to form a multilayered capsule around the Oocyte

Question 14

Graafian follicle/vesicular follicle

Answer 14

Main follicle develops to take up fluid forming an Antrum

The connective tissue surrounding the Oocyte and follicle divides into two layers, Theca interna and Theca externa

Question 15

Connective tissue (follicle cells) around the ovarian stoma divides into two layers

Answer 15

Theca externa

Theca interna

Question 16

FSH and LH level spike when

Answer 16

Just before day 14 of the menstrual cycle

This causes Graafian follicle to resume meiosis

Question 18

When follicle ruptures it releases

Answer 18

Oocyte, oocyte-cumulus cells mass

Question 19

Female gametogenesis

Answer 19

Oogonia 
    Mitosis 
Primary Oocyte (4N) 
    Ovulation (meiosis) 
Secondary Oocyte + polar body (2N) 
    Fertilization (meiosis) 
Definitive Oocyte + polar body (1N)

Question 20

Oogenesis begins in

Answer 20

Utero

Question 21

Spermatogenesis begins…

Answer 21

Just before puberty

Question 22

Meiotic cycle for Oocyte lasts

For a spermocyte

Answer 22

10-50 years

9 weeks

Question 23

Changes in uterine wall during the menstrual cycle

Answer 23

Smallest at 4 days

Largest at 21 days

Question 24

No implantation…

Answer 24

Corpus luteum degenerates and endometrium begins to dissociate

Question 25

Implantation occurs...

Answer 25

hCG keeps luteum to produce progesterone after which the placenta produces progesterone in 5 months

Question 26

Spermatogenesis Spermiogenesis

Answer 26

Four Spermatids result Conversion of spermatid to mature sperm cell

Question 27

Normal sperm count

Answer 27

Greater than 100 million sperms/ml | Lower than 10 million is considered infertile

Question 32

After Oocyte is released what is left over

Answer 32

Corpus luteum

Question 33

Primary Oocyte

Answer 33

Each Oocyte becomes invested in a single layer of squamous cell capsule, cell and capsule together are the primordial follicle, follicular cells prevent any further progression

Question 34

Corpus luteum after release of the Oocyte

Answer 34

Begins to proliferate to luteal cells, becomes an endocrine structure that serves to maintain the uterine endometrium in a condition ready to receive an embryo

Question 35

Follicular phase

Answer 35

Characterized by growth of the ovarian follicles 6-12 will grow at a time but only one will mature.

Question 36

Ovulation surge

Answer 36

When FSH and LH in the 13 or 14 day of menstrual cycle surge Stimulates the primary Oocyte with the Graafian follicle to resume meiosis leading to secondary Oocyte and polar body Arrests in the second Meiotic metaphase Then floats into the Antrum

Question 37

Luteal phase

Answer 37

Occurs after ovulation characterized by the presence of a corpus luteum

Question 38

Follicle ruptures...

Answer 38

Secondary Oocyte is released with Graafian fluid and cells of cumulus oophorus.

Question 39

FSH

Answer 39

Serves to stimulate the development of follicles and production of estrogen

Question 40

LH

Answer 40

Serves as a trigger for ovulation and stimulates the production of progesterone

Question 41

Estrogen

Answer 41

Low during first half of follicular phase Rises during second half of follicular phase peaks before LH surge Declines in beginning of luteal phase then increases again

Question 42

Progesterone

Answer 42

Low during follicular phase Increases around ovulation If pregnant levels remain high Rapidly decline if not pregnant

Question 43

Trisomy 21

Answer 43

Down's syndrome

Question 44

Trisomy 18

Answer 44

``` Edward syndrome Low set ears Small mouth Flection of hands Absent radius and ulna ```

Question 45

Trisomy 13

Answer 45

No skin developed | Only 5% live past 1 year

Question 46

Klinefelter syndrome

Answer 46

Lymphedema Only in males XXY genotype

Question 47

Turner syndrome

Answer 47

X monosomy Obviously female No ovaries

Question 48

Triple XXX syndrome

Answer 48

Mild symptoms | speech and self esteem issues

Question 49

Angelman syndrome Prader-Willi syndrome

Answer 49

Only in females Due to micro deletion on maternal chromosome 15 Only males Due to micro deletion on paternal chromosome 15 Lymphedema