Testis Flashcards
Cells that lie outside the seminiferous tubules are ________.
A) Spermatogonia
B) Spermatocyte
C) Sertoli cells
D) Leydig cells
D)
All of the following stages of spermiogenesis are correctly matched except ________.
A) Golgi phase: acrosomic vesicle formation
B) cap phase: acrosomic vesicle spreading over the nucleus
C) Acrosomal phase: nuclear and cytoplasmic elongation
D) Maturation phase: acquisition of motility
D)
LH acts on _______
A) Sertoli cells
B) Leydig cells
C) Myoid cells
D) germ cells
B) Leydig cells
The series of morphological changes a male germ cell undergoes to produce a mature male gamete are serially listed except ________ and ___________.
A) Spermatogonia (A)
B) Spermatogonia (B)
C) Primary spermatocyte
D) Secondary spermatocyte
E) Sparmatozoon
F) Spermatid
Switch E and F
All of the following about testosterone are false except _______ and _______.
A) Testosterone is highly produced in females
B) Testosterone is produced by seminiferous tubules
C) Testosterone is synthesized by the Leydig cells
D) Testosterone exerts positive feedback on the hypothalamus
E) Testosterone cannot be converted to estradiol in males
F) Testosterone is necessary for spermatogenesisC
C anf F
All of the following statements about the seminiferous tubules are correct except ________ and _________.
A) Special tubular structure in the testis
B) Produces sperm continuously throughout the male life cycle
C) Convoluted portion is called the tubulus rectus
D) Straight portion is called the tubulus contortus
E) surrounded by contractile peritubular cells
F) Joins with rete tubule
C and D; switch the names
True or false: The duration of spermatogenesis in stallions is 57 days
True
True or false: Sertoli cells are germ cells
False; Sertoli cells are somatic
True or false: Sperm cell acquires motility while transiting epididymis
True
True or false: The sequential ordering of stages along the length of the seminiferous tubule is called the spermatogenic wave
True
True or false: Spermatid is motile
False
Match the male germ cell to the definition
1) Cells that undergo meiosis II
2) Immature male gamete
3) Mature male gamete
4) Cells that undergo mitotic divisions
5) Cells that undergo meiosis I
A) Spermatogonia
B) Primary spermatocyte
C) Secondary spermatocyte
D) Spermatid
E) Spermatozoon
1) C)
2) D
3) E
4) A
5) B
Describe the external and internal morphology of the testis
External: capsule - visceral vaginal tunic, tunica albuginea
Internal: tissue parenchyma and mediastinum
Define lobules, and the compartments that contain them
Tissue projections of tunica albuginea divides the parenchyma into lobules. The tubular compartment has seminiferous tubules, and the interstitial compartment has vessels, lymphatic, nerves, and Leydig cells
Define mediastinum and the tubules that pass through it
The central connective tissue core. Rete tubules are tiny channels through which spermatozoa are transported out of the testis
Describe the seminiferous tubule
A special tubular structure in the testis that produces sperm continuously throughout the male life cycle (site of spermatogenesis); composed of a convoluted portion (tubulus contortus) and a straight portion (tubulus rectus); surrounded by contractile peritubular cells; joins with rete tubule
What are Sertoli cells and what do they do?
They’re somatic cells (also called sustentacular cells); they provide morphogenetic support via cell-cell interactions (mechanical and nutritional support) and play a critical role during the process of spermatogenesis and express receptors for FSH. They produce androgen binding protein (ABP), sulfated glycoproteins (SGP), and transferrin and inhibin
What is the significance of the blood-testis barrier?
Prevents immunologic destruction of developing germ cells
What is spermatogenesis?
A finely regulated process of germ cell multiplication and differentiation leading to the production of spermatozoa in the seminiferous tubules
What are the three phases of spermatogenesis?
1) Spermatocytogenesis: A proliferative phase where spermatogonia undergo a series of mitotic divisions to form primary spermatocytes
2) Meiosis: the primary spermatocytes undergo reduction division to become secondary spermatocytes which produce round haploid spermatids
3) Spermiogenesis: differentiation of the haploid, round spermatids to form the elongated and flagellated spermatozoa by a series of morphologic changes
What are the four phases of spermiogenesis, and what happens in each?
Golgi phase: acrosomic vesicle formation
Cap phase: acrosomic vesicle spreading over the nucleus
Acrosomal phase: nuclear and cytoplasmic elongation
Maturation phase: final assembly that forms a spermatozoon
What is spermiation?
Release of formed germ cells into the lumen of the seminiferous tubules
What is a spermatozoon?
Mature male gamete; highly specialized structure containing unique features compared to a somatic cell including: small size, presence of a flagellum for movement, and unique DNA complement and chromatin packaging; delivers male genetic material to an oocyte during fertilization;
What is the spermatogenic wave?
The sequential ordering of stages along the length of the seminiferous tubule
