Lect 6. Spermatogenesis and Oogenesis Flashcards
Spermatogenesis
(1)____ enter the testes early in development but do not develop into (2)___ until puberty.
Once active, they divide mitotically to create (3)_____.
- Primordial germ cells
- spermatogonia
- primary spermatocytes
Spermatogenesis
Primordial germ cells enter the testes early in development but do not develop into spermatogonia until (1)____.
→ Once active, they divide (2)_____ (mitotically/meiotically) to create primary spermatocytes.
- puberty
- mitotically
Spermatogenesis
How are primary spermatocytes formed?
Primordial germ cells enter the testes early in development but do not develop into spermatogonia until puberty.
→ Once active, they divide mitotically to create primary spermatocytes.
During Spermatogenesis
→ the first phase of meiosis produces
2 secondary spermatocytes.
During Spermatogenesis
→ each secondary spermatocyte completes the second phase of meiosis to form ____
haploid spermatids.
During Spermatogenesis
→ each (1)____ completes the second phase of (2)___ to form haploid spermatids.
- secondary spermatocyte
- meiosis
Spermatids mature into (1)___ in a process called (2)___.
- spermatozoa
- spermiogenesis
Spermiogenesis
→ Identify
Spermiogenesis produces ___
“classic” sperm cell
Spermiogenesis produces “classic” sperm cell
- ___ expanding around nucleus
- mitochondria cluster in middle piece, also called ____
- ___ extending posteriorly from tail piece
- acrosome
- mitochondrial sheath
- flagellum
In the process of Spermiogenesis, each spermatid sheds most of its cytoplasm as ___
residual body
Spermatogenesis
As spermatogonia divide and mature into (1)___, they migrate closer to (2)____; they are not open until (3)___
- spermatozoa
- the lumen of seminiferous tubules
- puberty
Spermatogenesis
As ____ divide and mature into spermatozoa, they migrate closer to the lumen of seminiferous tubules; they are not open until puberty
spermatogonia
Identify cell 1
→ Event?
Spermatogonium - DNA replication
Identify cell 2
→ Event?
Primary spermatocyte - First meiotic division
Identify cell 3
→ Event?
secondary spermatocytes- Second meiotic division
Identify cell 4
Spermatids - Immature haploid gametes
Identify cell 5
Spermatozoa - Haploid gametes
What happen between 2 & 3?
First meiotic division completed
What happen between 3 & 4
Second meiotic division completed
What happen between 4 & 5
Spermiogenesis
Spermatogenesis
Which hormone is necessary for maturation of spermatozoa?
Testosterone
Spermatogenesis
The role of Sertoli cells
Sertoli cells concentrate testosterone released by nearby Leydig cells
(Testosterone necessary for maturation of spermatozoa)
Oogenesis
(1)___ enter the ovaries early in development and develop into (2)___.
→ They divide mitotically to create (3)__
- Primordial germ cells
- oogonia
- primary oocytes.
Primordial germ cells enter the (1)___ early in development and develop into oogonia.
→ They divide (2)____ (meiotically/mitotically) to create primary oocytes.
- ovaries
- mitotically
Oogenesis
Starting from ____
→ the first phase of meiosis will produce a single secondary oocyte and the first polar body, a small residual cell with very little cytoplasm.
a primary oocyte
Oogenesis
Starting from a primary oocyte
→ the first phase of meiosis will produce ___ (2)
a single secondary oocyte and the first polar body
Oogenesis
What is a polar body?
a small residual cell with very little cytoplasm.
Oogenesis
The second phase of meiosis will create __
1 mature oocyte and 3 polar bodies.
Oogenesis
→ identify
Oogenesis
→ Which one is the ovum?
Which phase will produce a single secondary oocyte and the first polar body?
the first phase of meiosis
Which phase will create 1 mature oocyte and 3 polar bodies?
The second phase of meiosis
Follicles
Early in development, XX germ cells begin the first phase of meiosis but arrest in (1)___ forming oocytes surrounded by (2)__ of the ovary
- prophase
- follicular cells
Follicles
Early in development, XX germ cells begin the first phase of meiosis but arrest in prophase forming oocytes surrounded by follicular cells of the ovary
→ together, oocyte and follicular cells create (1)___
→ follicular cells grow to become cuboidal in (2)___
- primordial follicle
- primary follicle
Identify
Follicles
As primary follicles mature, follicular cells proliferate to become stratified and secrete ____
a layer of glycoprotein around oocyte called zona pellucida
Follicles
As primary follicles mature, ____ proliferate to become stratified and secrete a layer of glycoprotein around oocyte called zona pellucida
follicular cells
Follicles
As ___ mature, follicular cells proliferate to become stratified and secrete a layer of glycoprotein around oocyte called zona pellucida
primary follicles
Follicles
During each (1)___, several primary oocytes grow larger and follicular cells surrounding them; proliferate to become (2)____
- menstrual cycle
- granulosa cells
Follicles
During each menstrual cycle, several ____ grow larger and follicular cells surrounding them; proliferate to become granulosa cells
primary oocytes
Follicles
During each menstrual cycle, several primary oocytes grow larger and ___ surrounding them; proliferate to become granulosa cells
follicular cells
IDENTIFY
Secondary follicle
→ Identify
Small fluid- filled lacunae
Follicles
At this point, the follicle grows so large that (1)___ develop within granulosa cells and whole assembly is (2)___
- fluid-filled lacunae
- secondary follicle
Follicles
At this point, the follicle grows so large that fluid-filled lacunae develop within ___ and whole assembly is secondary follicle
granulosa cells
Follicles
As secondary follicles mature, lacunae fuse to form (1)___
→ the follicular cells that remain in contact with oocyte are called (2)___
- follicular antrum
- cumulus oophorus
Follicles
What is cumulus oophorus?
the follicular cells that remain in contact with oocyte
Maturing secondary follicle
→ Identify
Graafian follicle
Prior to (1)____, the follicular antrum enlarges, creating mature (2)____
- ovulation
- Graafian follicle
Graafian follicle
Prior to ovulation, ____ enlarges, creating mature Graafian follicle;
the follicular antrum
Graafian follicle
→ (1)___ is a connective tissue layer that connects the follicle to the rest of ovary; just inside that layer is the (2)____ secreting hormones that affect the oocyte
- theca externa
- theca interna
Graafian follicle
→ What is theca externa?
a connective tissue layer that connects the follicle to the rest of ovary
Graafian follicle
→ The role of theca interna
secreting hormones that affect the oocyte
IDENTIFY
During each menstrual cycle, how many follicles reach full maturity?
ONLY 1
(**During each menstrual cycle, several follicles begin maturing but typically only 1 reaches full maturity)
