Embryology Test 1 Flashcards
During spermatozoa maturation protamines replace histones to facilitate chromatin condensation. When or where are sperm DNA protamines removed and replaced by histones?
In the oocyte after fertilization
When does the zona pellucida “hatching” occur?
Blastocyst stage
The amniotic cavity is formed when?
A cavity forms in the epiblast
The chorionic cavity or extraembryonic coelom forms between which two layers?
Splanchnic extraembryonic mesoderm and somatic extraembryonic mesoderm.
Where does the intraembryonic coelom form during the week 3 of embryonic development?
Lateral plate mesoderm
When does tetras formation and crossing over occur?
Prophase 1 of meiosis 1
How many chromosomes and how many copies of the DNA (n) would be present in a human primary oocyte?
46 and 4N
How many chromosomes and how many copies of DNA (n) would be present in a human secondary oocyte?
23 and 2N
How long does the embryonic period last?
8 weeks
Which sequence best reflects the sperm pathway through the male reproductive system?
Seminiferous tubules, rete testis, efferent ductules, epididymis, ductus deferens, ejaculatory duct, prostatic urethra, membranous urethra, penile urethra
Approximately 60% of seminal fluid derives from a yellowish, alkaline, viscous fluid produced by which source?
Seminal vesicles
Which structure would not be included in or related to the female vestibule?
Mons pubis
When during the cell cycle does centriole replication occur?
S phase
Sister chromatid separation due to kinetochore microtubule shortening occurs during which phase of mitosis?
Anaphase
Meiosis occurs during which phase of spermatogenesis?
Spermatocyte phase
During spermiogenesis the spermatid actually reorients so the flagellum will extend into the seminiferous tubule lumen. What event initiates this reorientation?
Acrosomal sac formation
The lining of the body of the uterus is referred to as the?
Endometrium
Which area of the female reproductive tract is characterized by by large glands that shift their secretion around the time of ovulation?
Endocervical canal
Which area of the female reproductive tract has a lining epithelium described as a nonkeratinized stratified squamous epithelium and there are no glands?
Vagina
How would you classify an ovarian follicle made up of multiple layers of Granulosa cells with several small fluid filled spaces?
Secondary follicle
When does zona pellucida formation begin?
Early primary follicle
Identify this collection of cells. (Large oocyte surrounded by one layer of follicle cells, with a small zona pellucida in between, and surrounded by stroma cells
Early primary follicle
Which cells or structures would not be present in a mature Graafian immediately prior to ovulation?
Primary oocyte
Circulating levels of which hormone produced by the ovary will reach their peak level during the follicular stage?
Estrogen