Repro: Male Flashcards
For production of hormones and spermatozoa
Testes
Consists of testes, genital ducts, accessory gland and penis.
Male Reproductive System
Main male reproductive hormone. Important for spermatogenesis. Sexual differentiation during embryonic and fetal development. Control of gonadotropin secretion.
Testosterone
Male Reproductive Hormones
Testosterone& Dihydrotestosterone
Acts on many organs during puberty & adulthood
DHAT
Produce secretions. Nutrients for spermatozoa. Propel spermatozoa outside.
Genital ducts and accessory gland
Capsule of DCT that surrounds the testes. Thickened on the posterior side of the testes. Forms mediastinum of the testes.
Tunica albuginea
Occupied by one to four semineferous tubule
Lobules
Penetrate the organ and divides it into testicular lobules, _________.
Mediastinum testes. Pyramidal compartments.
Surrounded by interstitial LCT rich in blood & lymphatic vessels, nerves & endocrine interstitial cells of Leydig. Produce spermatozoa.
Semineferous tubules
Secrete testosterone and androgens
Leydig cells
Testes develop retroperitoneally in ________ of embryonic cavity. Suspended within two sides of scrotum at ends of _________. Carries with it a serous sac.
Dorsal wall. Spermatic cords.
Serous sac derived from peritoneum which consist if two layers.
Tunica vaginalis
Layer of tunica vaginalis that covers the tunica albuginea on anterior and lateral side
Inner visceral layer
Layer of tunica vaginalis that lines scrotum
Outer parietal layer
Important in the regulation of spermatogenesis
Temperature
Temperature: below core body temperature of ____. Testicular temperature of _____ maintained by ______.
37’C. 34’C. Scrotal sac.
Surrounds each testicular artery. With cooler blood from testes. Can draw heat from arterial blood by a ____________.
Pampiniform venous plexus. Countercurrent heat-exchange system.
Relaxation or Contraction of these moves testes away from/closer to the body
Dartos muscle(scrotum) & Cremaster muscle(spermatic cords)
Failure of descent of testes in scrotum. Maintains testes at core body temperature. Inhibits spermatogenesis.
Cryptorchidism
Produces sperm 2x10 to the 8th per day. Convoluted loop linked via __________ to the Rete testis. Has two types of cells.
Seminiferous tubules. Straight tubule.
Labyrinth of epithelium lined channels embedded in Mediastinum testes
Rete Testis
Short, narrow segment.
Straight tubule
Connect rete testis to head of epididymis
Efferent ductules
Seminiferous tubules are lined by
Complex stratified epithelium or Germinal/Seminiferous Epithelium
Flattened. Smooth muscle like cells. Allow weak contractions of the tubule.
Myoid cells
Basement membrane of Seminiferous tubule is covered by ________ w/ innermost layer _______.
Fibrous CT. Myoid cells.
Occurs in the CT of the seminiferous tubules
Interstitial cells
Nondividing cell. Produces inhibin.
Supporting/Sustentacular/Sertoli cells
Proliferative. Comprise 4-8 concentric cell layers. Produce cells that become sperm.
Spermatogenic lineage
Begins at puberty
Spermatogenesis
Spermatogenesis 1: primitive germ cell. Relatively small _____ cell. Located ______ in epithelium next to BM. different stages recognized by shape & staining properties of their nuclei.
Spermatogonium. Round. Basally.
Spermatogenesis 2: spermatogonia with ________ nuclei. Divides infrequently. Gives rise to SC & PC.
Stem cell. Dark ovoid.
Spermatogenesis 3: ______ staining ovoid nuclei and divide more rapidly.
Progenitor cell. Pale staining.
Spermatogenesis 4: undergo clonal divisions. Remains interconnected as a _________. Forms Type B Spermatogonia.
Type A Spermatogonia. Syncytium.
Spermatogenesis 5: formed by Type A Spermatogonia. Have more ______ nuclei. Undergoes final _______ division. Produce ________.
Type B Spermatogonia. Spherical. Mitotic. 1’ Spermatocyte.
Spermatogenesis 6: spherical, euchromatic nuclei, replicate their DNA, each chromosome consist of duplicate chromatids (_______) DNA=____, largest cells of spermatogenic lineage. Presence of partially condensed chromosomes.
Primary spermatocyte. Diploid. 4N.
Conversion from primary spermatocyte to secondary spermatocyte
1st meiotic division
Spermatogenesis 7: 23 chromosomes, 2 chromatids, DNA= ___, rare, short-lived & remain in ________ only brief then enters ________.
2’ Spermatocyte. 2N. Interphase. Second meiotic division.
Spermatogenesis 8: due to conversion of 2’ Spermatocyte thru 2nd meiotic division. Haploid cells (2), 23 chromosomes. 1N= no ________ (DNA replication) occurs between 1st & 2nd meiotic division.
Spermatids. S phase.
Divides into progenitor cells & stem cells
Type A Spermatogonia
Remain as separate cells
Stem cells
Have increase cytokines __________. Cells attached to one another by Intercellular bridges of cytoplasm.
Progenitor cells. After telophase.
Cells remain linked through period of meiosis
Spermatogenic Syncytium
Allows free communication among cells derived from a single type A spermatogonia. Allows developing spermatid to share the cytoplasm of neighboring cells. Coordinate division & differentiation.
Intercellular bridges of Cytoplasm
Final stage in sperm production. No cell division.
Spermiogenesis
In Spermiogenesis: spermatids transform in
Spermatozoa