Regulation of Gonadal Activities

Question 1

Control of Spermatogenesis:
______ stimulates both steroidogenic ang gametogenic testicular function

Answer 1

LH

Question 2

Control of Spermatogenesis:
LH indirectly influences spermatogenesis through

Answer 2

the action of testosterone produced by the Leydig cells

Question 3

Control of Spermatogenesis:
_________ influences the activity of the Sertoli cells which aid in spermiogenesis

Answer 3

FSH

Question 4

Control of Spermatogenesis:
there is a _____________ activity of Sertoli cells, in accordance with the requirements of spermatogenesis

Answer 4

cyclic variation activity

Question 5

is also produced in a paracrine fashion by the Sertoli cells, for spermatocytes
undergoing meiosis

Answer 5

Insulin-like growth factor 1 (IGF-1)

Question 6

Control of Spermatogenesis- Noxious agents:
Sensitivity of germinal cells of seminiferous tubules to harmful agents ______ as differentiation proceeds to ______

Answer 6

increases;
spermatid stage

Question 7

Control of Spermatogenesis - Noxious agents:
Irraditation produces destructive effect on dividing cells, where _______ are more sensitive than ______

Answer 7

spermatogonia are more sensitive than spermatocytes

Question 8

Control of Spermatogenesis - Noxious agents:
Irradiation causes mutations, translocations and deletions to the

Answer 8

spermatocyte DNA

Question 9

Control of Spermatogenesis - Noxious agents:
_______ are sensitive to mutagenic effects of x-irradiation, while _______ are less sensitive and _______ are resistant

Answer 9

Spermatids,
Spermatozoa,
Spermatogonia

Question 10

Control of Spermatogenesis - Noxious agents:
Interval between testicular damage and appearance of abnormal cells in semen depends on the

Answer 10

nature of the insult,
cell type affected,
duration of spermatogenesis,
epididymal migration time in species

Question 11

Control of Spermatogenesis - Noxious agents:
If ________ are damaged, the semen is affected soon after application of noxious agent

Answer 11

Epididymal spermatozoa

Question 12

Control of Spermatogenesis - Noxious agents:
If effect is on _______, damage will not be apparent in the semen for several weeks after the damage is done

Answer 12

Spermatogonia

Question 13

Control of Spermatogenesis - Noxious agents:

Question 14

Control of Spermatogenesis - Noxious agents:
Type of change in seminal quality is related to the_______

Answer 14

type of damage produced

Question 15

Control of Spermatogenesis - Noxious agents: (Type of change in seminal quality is related to the type of damage produced)

Death of germinal cells causes ________

Answer 15

decreased number of spermatozoa

Question 16

Control of Spermatogenesis - Noxious agents: (Type of change in seminal quality is related to the type of damage produced)

________ results to morphologic defects

Answer 16

Abnormal spermateliosis

Question 17

Control of Spermatogenesis - Noxious agents: (Type of change in seminal quality is related to the type of damage produced)

Damage to spermatozoal genetic apparatus results in ________

Answer 17

embryonic and fetal death or teratogeny

Question 18

Control of Spermatogenesis-Seasonal Variations:
Males show ____ seasonal variation in testicular function

Answer 18

less

Question 19

Control of Spermatogenesis - Seasonal Variations:
The quality of ejaculate are optimal during the __________

Answer 19

reproductive season

Question 20

Control of Spermatogenesis - Seasonal Variations:
Seasonal changes in LH, FSH, and testosterone are influenced by

Answer 20

photoperiod

Question 21

Control of Spermatogenesis - Seasonal Variations:
____ and ______ are influenced by season and photoperiod

Answer 21

Testicular weight and male sexual behavior

Question 22

Control of Spermatogenesis - Seasonal Variations:
In some species, during the hot summer months

Answer 22

seminal quality and male fertility tend to decline during the hot summer months

Question 23

Control of Spermatogenesis - Scrotal Position:
Scrotal position is an indicator of ________ for spermatogenesis

Answer 23

optimal temperature

Question 24

Control of Spermatogenesis - Scrotal Position:
Normal adult males of most domestic animals

Answer 24

scrotal testes which provides a lower intratesticular temperature essential for normal gametogenic function

Question 25

Control of Spermatogenesis - Scrotal Position: Scrotal descent

Answer 25

an evolutionary trait to maintain a temperature 2-4°C lower than the abdomen

Question 26

Control of Spermatogenesis - Scrotal Position: Spermatogenesis is impaired when heat is applied to the scrotum or when the scrotum is insulated against heat loss

Answer 26

True

Question 27

Control of Spermatogenesis - Scrotal Position: Bilaterally cryptorchid males

Answer 27

sterile

Question 28

Control of Spermatogenesis - Scrotal Position: Unilaterally cryptorchid males

Answer 28

have lower testicular weight in undescended testes and display impaired spermatogenesis

Question 29

Control of Spermatogenesis - Scrotal Position: Fat

Answer 29

acts as an insulator, making it detrimental to spermatogenesis

Question 30

Control of Spermatogenesis - Scrotal Position: Constitute an effective thermoregulatory mechanism

Answer 30

Scrotum, Cremaster muscle, Spermatic vasculature

Question 31

Control of Spermatogenesis - Scrotal Position: Spermatic artery and pampiniform plexus

Answer 31

Provide a heat exchange

Question 32

Control of Spermatogenesis - Scrotal Position: Tunica dartos and cremaster muscle during hot weather

Answer 32

relax, so testes is separated from the abdominal wall to allow maximum heat loss

Question 33

Control of Spermatogenesis - Scrotal Position: In cold weather

Answer 33

Muscles contract to reduce heat loss

Question 34

Control of Spermatogenesis - Scrotal Position: Homeothermy

Answer 34

Spermatogenesis depends on homeothermy

Question 35

Control of Spermatogenesis - Scrotal Position: Fever

Answer 35

increases testicular temperature, resulting in disturbed spermatogenesis

Question 36

Control of Spermatogenesis - Scrotal Position: Cooling vs Heat

Answer 36

Spermatogenesis is more resistant to cooling than heat, since the tunica dartos and cremaster muscles contract to protect the testes

Question 37

Control of Spermatogenesis - Nutrition: Malnutrition in prepuberal males and postpubertal males

Answer 37

Malnutrition constitutes a greater stress to spermatogenesis in prepuberal males than in postpubertal males

Question 38

Control of Spermatogenesis - Nutrition: Energy-deficient diets

Answer 38

affects gonadotropin secretion, resulting to decline in libido, seminiferous epithelium damage, and low ejaculate volume

Question 39

Control of Spermatogenesis - Nutrition: Hypovitaminosis A

Answer 39

causes: poor seminal quality, testicular atrophy, hypoplasia of accessory sex glands, delayed puberty

Question 40

Control of Spermatogenesis - Nutrition: Hypovitaminosis E

Answer 40

causes testicular damage

Question 41

Control of Spermatogenesis - Nutrition: Mineral deficiencies and feeding with phytoestrogens, goitrogens, and nitrates

Answer 41

associated with impaired reproductive performance in males