p.1
Spermatogenesis Process
What is spermatogenesis?
The process of sperm cell development.
p.1
Factors Affecting Spermatogenesis
What factors can affect spermatogenesis?
Hormonal levels, temperature, and environmental factors.
p.1
Functions of Sertoli Cells
What are the functions of Sertoli cells?
Support and nourish developing sperm cells.
p.1
Hormones Produced by the Testis
What hormones are produced by the testis?
Testosterone and inhibin.
p.13
Composition and Function of Semen
What is the significance of the seminal vesicles during ejaculation?
They contribute to the volume and nutrient content of semen, aiding sperm survival and movement.
p.3
Hormones Produced by the Testis
What hormones are produced by the male reproductive system?
Hormones that develop secondary sexual characteristics and are involved in feedback mechanisms relating to spermatogenesis.
p.5
Spermatogenesis Process
What is spermiogenesis?
The final stage of sperm development where spermatid becomes a motile spermatozoa.
p.7
Hormones Produced by the Testis
What hormone stimulates Sertoli cells to form estrogens from testosterone?
Follicle stimulating hormone (FSH).
p.2
Structure and Function of Male Reproductive Organs
What are the internal genitalia in the male reproductive system?
The vas deferens, seminal vesicles, ejaculatory duct, and prostate.
p.11
Biological Effects of Androgens
What effects do androgens have in the body?
They stimulate spermatogenesis and the growth of secondary sex characteristics.
p.10
Functions of Sertoli Cells
What role do Sertoli cells play in the nutrition of spermatids?
They provide nourishment through glycogen and help in the maturation of spermatids into spermatozoa.
p.9
Functions of Sertoli Cells
What effect does activin have on FSH and LH?
Activin increases FSH release and enhances LH function.
p.16
Spermatogenesis Process
What does the acrosome of spermatozoa contain?
Digestive enzymes like hyaluronidase and proteolytic enzymes.
p.22
Biological Effects of Androgens
What role does testosterone play in bone density?
It helps maintain bone density and strength.
p.17
Spermatogenesis Process
What changes occur in the acrosome during capacitation?
Calcium ions cause changes that allow the acrosome to release enzymes rapidly.
p.21
Hormones Produced by the Testis
How does testosterone influence red blood cell production?
It stimulates the secretion of erythropoietin hormone, increasing the formation of RBCs.
p.11
Hormones Produced by the Testis
What do Leydig cells produce?
Androgens such as testosterone, androstenedione, and dehydroepiandrosterone (DHEA).
p.17
Spermatogenesis Process
What is the significance of the acrosome releasing enzymes?
It allows the sperm to penetrate the granulosa cell mass surrounding the ovum.
p.6
Hormones Produced by the Testis
What is necessary for the conversion of spermatids to sperm?
Stimulation by follicle-stimulating hormone.
p.3
Hormones Produced by the Testis
What role do hormones play in male reproductive physiology?
They develop secondary sexual characteristics and regulate spermatogenesis through feedback mechanisms.
p.10
Functions of Sertoli Cells
What is one function of Sertoli cells related to testosterone?
Secretion of androgen binding protein (ABP) to bind testosterone and increase its concentration in seminiferous tubule fluid.
p.8
Factors Affecting Spermatogenesis
What dietary conditions can arrest spermatogenesis?
Complete starvation and protein deficiency.
p.18
Spermatogenesis Process
What is the function of the substances in the cortical granules?
They prevent binding of additional sperm and cause already bound sperm to fall off.
p.13
Composition and Function of Semen
How do seminal vesicles contribute to ejaculation?
They empty their contents, adding greatly to the bulk of the ejaculated semen.
p.8
Factors Affecting Spermatogenesis
What other factors can depress spermatogenesis?
Oxygen lack, various bacterial and chemical toxins.
p.22
Biological Effects of Androgens
How does testosterone affect muscle mass?
It increases muscle mass and strength.
p.22
Biological Effects of Androgens
How does testosterone influence libido?
It enhances sexual desire and libido.
p.20
Regulation of Testosterone Secretion
How does testosterone level change with age in males?
It declines somewhat with age.
p.11
Regulation of Testosterone Secretion
What hormone stimulates Leydig cells to produce androgens?
Luteinizing hormone (LH).
p.19
Hormones Produced by the Testis
What is testosterone synthesized from?
Cholesterol in the Leydig cells and androstenedione from the adrenal cortex.
p.10
Functions of Sertoli Cells
How do Sertoli cells support spermatogenesis?
By secreting estrogen from androgen.
p.5
Spermatogenesis Process
What does spermiation refer to?
The release of mature spermatozoa from Sertoli cells into the lumen of seminiferous tubules.
p.19
Regulation of Testosterone Secretion
Which hormone controls the secretion of testosterone?
LH (Luteinizing Hormone).
p.25
Mechanism of Erection
How is an erection terminated?
By sympathetic vasoconstrictor impulses to penile arterioles.
p.21
Hormones Produced by the Testis
What is one essential function of testosterone at puberty?
It is essential for spermatogenesis.
p.21
Biological Effects of Androgens
What anabolic effects does testosterone have?
It increases protein synthesis and decreases protein breakdown, leading to increased growth rate.
p.6
Hormones Produced by the Testis
What does follicle-stimulating hormone do in the process of spermatogenesis?
It acts on Sertoli cells to stimulate spermatid maturation (spermiogenesis).
p.20
Metabolism of Testosterone
What happens to a small amount of circulating testosterone?
It is converted to estradiol.
p.8
Factors Affecting Spermatogenesis
What is the optimum temperature for spermatogenesis?
About 3-5 degrees below body temperature.
p.2
Structure and Function of Male Reproductive Organs
What are the secondary or accessory sexual organs in the male reproductive system?
Genitalia, which include internal and external genitalia.
p.23
Composition and Function of Semen
What is semen?
The milky fluid ejaculated during the male sexual act.
p.15
Composition and Function of Semen
What is a key component of the fluid produced by seminal vesicles?
Fructose, which provides energy for sperm.
p.2
Structure and Function of Male Reproductive Organs
What are the external genitalia in the male reproductive system?
The epididymis, scrotum, penis, and bulbourethral glands.
p.15
Composition and Function of Semen
How does the prostate gland contribute to semen?
By secreting a slightly alkaline fluid that helps neutralize the acidity of the female reproductive tract.
p.7
Hormones Produced by the Testis
What effect does growth hormone have on spermatogonia?
It promotes early division of spermatogonia.
p.23
Composition and Function of Semen
What are some key substances found in semen?
Fructose, buffers (phosphates and bicarbonates), fibrinogenase, fibrinolysin, and hyaluronidase.
p.4
Spermatogenesis Process
What is the significance of mitosis and meiosis in spermatogenesis?
It ensures a continuous supply of spermatogonia.
p.16
Spermatogenesis Process
What is the end result of spermiation?
The structure of mature sperm.
p.22
Biological Effects of Androgens
What effect does testosterone have on fat distribution?
It influences fat distribution in the body.
p.21
Biological Effects of Androgens
How does testosterone affect electrolyte and water retention?
It causes moderate retention of Na+, K+, H2O, Ca2+, SO4, and PO4.
p.14
Functions of Sertoli Cells
How does prostatic fluid affect sperm motility and fertility?
It neutralizes the acidity of other seminal fluids, enhancing sperm motility and fertility.
p.18
Spermatogenesis Process
What happens after the first sperm penetrates the zona pellucida of the ovum?
Calcium ions diffuse inward through the oocyte membrane.
p.15
Composition and Function of Semen
What role do prostate glands play in male reproduction?
They produce a fluid that helps to protect and energize sperm in semen.
p.9
Functions of Sertoli Cells
How does inhibin affect FSH release?
Inhibin decreases FSH release from the anterior pituitary.
p.13
Composition and Function of Semen
What is the role of fructose in seminal fluid?
It provides considerable nutrient value for the sperm.
p.23
Composition and Function of Semen
What is the pH level of semen?
Alkaline, with a pH of 7.4.
p.22
Functions of Sertoli Cells
What is one primary function of testosterone in males?
It promotes the development of male reproductive tissues.
p.10
Functions of Sertoli Cells
What does the blood-testis barrier prevent?
It prevents large molecules and antigenic products of germ cell division from entering circulation.
p.9
Functions of Sertoli Cells
What condition is associated with the presence of Müllerian duct derivatives in genetically male individuals?
Persistent Müllerian duct syndrome (PMDS).
p.17
Spermatogenesis Process
How does capacitation affect the permeability of the sperm membrane?
It becomes more permeable to calcium ions.
p.6
Hormones Produced by the Testis
How does follicle-stimulating hormone maintain high testosterone concentration in seminiferous tubular fluid?
By promoting secretion of androgen binding protein (ABP) and sensitizing Leydig cells to LH.
p.3
Spermatogenesis Process
What is the primary function of the male reproductive tract?
To produce, maintain, and transport viable spermatozoa.
p.5
Spermatogenesis Process
What occurs during spermatocytogenesis?
The conversion of spermatogonia to spermatid.
p.18
Spermatogenesis Process
What do calcium ions cause to be released from the oocyte?
Multiple cortical granules by exocytosis.
p.13
Composition and Function of Semen
What do the seminal vesicles secrete?
A mucoid material containing fructose, citric acid, and other nutrient substances, as well as prostaglandins and fibrinogen.
p.16
Spermatogenesis Process
What is the initial state of spermatozoa after formation?
Initially unable to move.
p.17
Spermatogenesis Process
What role do uterine and fallopian tube fluids play in capacitation?
They wash away inhibitory factors that suppress sperm activity.
p.7
Hormones Produced by the Testis
What happens to spermatogenesis in the absence of growth hormone?
It is severely deficient or absent, causing infertility.
p.23
Composition and Function of Semen
What happens to semen after ejaculation?
It clots but then liquefies again due to fibrinolysin.
p.21
Hormones Produced by the Testis
What does testosterone contribute to the development of at puberty?
Development of secondary sex organs.
p.17
Spermatogenesis Process
What effect do calcium ions have on sperm movement?
They strengthen the movement of the flagella.
p.1
Regulation of Testosterone Secretion
How is testosterone secretion regulated?
Through feedback mechanisms involving the hypothalamus and pituitary gland.
What is the mechanism of erection?
Increased blood flow to the penis due to relaxation of smooth muscles.
p.25
Mechanism of Erection
What initiates an erection?
Dilatation of the arterioles of the penis.
p.7
Hormones Produced by the Testis
What role do estrogens play in spermatogenesis?
They are essential for spermiogenesis.
p.17
Spermatogenesis Process
What is capacitation in spermatozoa?
The process that makes sperm capable of penetrating the ovum.
p.7
Hormones Produced by the Testis
Which hormones are necessary for controlling metabolic functions of the testes?
Growth and thyroid hormones.
p.8
Factors Affecting Spermatogenesis
What effect does irradiation have on spermatogenesis?
It leads to irreversible damage in the germinal epithelium.
p.4
Spermatogenesis Process
What occurs to some spermatogonia at puberty?
They undergo mitosis continuously and enter into meiosis.
p.14
Functions of Sertoli Cells
What does the prostate gland secrete?
A thin, milky fluid containing calcium, citrate ion, phosphate ion, a clotting enzyme, and profibrinolysin.
p.17
Spermatogenesis Process
What happens to the sperm membrane during capacitation?
It becomes weaker due to the loss of cholesterol covering.
p.21
Hormones Produced by the Testis
What secondary sex characteristics does testosterone help develop?
It contributes to the development of secondary sex characteristics (specifics in table).
p.6
Hormones Produced by the Testis
What is the role of luteinizing hormone in spermatogenesis?
It stimulates Leydig cells to secrete testosterone.
p.15
Composition and Function of Semen
What is the primary function of the seminal vesicles?
To produce a fluid that nourishes sperm and forms a significant portion of semen.
p.11
Regulation of Testosterone Secretion
How does FSH affect Leydig cells?
FSH increases the response of Leydig cells to LH.
p.16
Spermatogenesis Process
What is spermiation?
The process of release of mature spermatozoa from Sertoli cells into the lumen of the seminiferous tubule.
p.4
Spermatogenesis Process
What happens to spermatogonia before puberty?
They remain quiescent within layers of seminiferous tubules.
p.10
Functions of Sertoli Cells
What structure do Sertoli cells form that protects germ cells?
The blood-testis barrier through tight junctions between adjacent Sertoli cells.
p.9
Functions of Sertoli Cells
What is the role of Anti-Müllerian Hormone (AMH) during embryogenesis?
AMH prevents the development of the Müllerian ducts.
p.13
Biological Effects of Androgens
What are the two believed functions of prostaglandins in fertilization?
1) They react with female cervical mucus to make it more receptive to sperm movement. 2) They may cause reverse peristaltic contractions in the uterus and fallopian tubes to move sperm toward the ovaries.
p.14
Functions of Sertoli Cells
What is the role of the clotting enzyme secreted by the prostate gland?
It clots semen to hold it around the cervix.
p.1
Hormones Produced by the Testis
What are the functions of testosterone?
Regulates male reproductive tissues and secondary sexual characteristics.
p.1
Biological Effects of Androgens
What are the biological effects of androgens?
Influence prenatal development and postnatal growth and behavior.
p.5
Spermatogenesis Process
What are the two stages of sperm production?
1. Spermatocytogenesis 2. Spermiogenesis.
p.4
Spermatogenesis Process
What are the initial cells involved in spermatogenesis?
Germ cells called spermatogonia.
p.18
Spermatogenesis Process
Why does almost only one sperm enter the oocyte during fertilization?
Due to the release of cortical granules that block additional sperm binding.
p.21
Hormones Produced by the Testis
What role does testosterone play during intrauterine life?
It stimulates the maturation of the Wolffian ducts, developing into male internal genital organs.
p.16
Spermatogenesis Process
How does the flagella of spermatozoa become motile?
It must become motile but is not used until ejaculation.
p.14
Functions of Sertoli Cells
What is the function of fibrinolysin in prostatic fluid?
It dissolves the clot formed by the clotting enzyme.
p.12
Maturation and Storage of Sperm
Where is sperm stored after maturation?
Some in the epididymis, most in the vas deferens.
p.22
Biological Effects of Androgens
What is the impact of testosterone on mood?
It can affect mood and energy levels.
p.20
Transport of Testosterone
What is the primary protein that binds testosterone in plasma?
Gonadal steroid binding globulin (GBG) or sex steroid-binding globulin.
p.25
Mechanism of Erection
How does an erection increase the length and strength of the penis?
Veins are compressed, blocking outflow of blood.
p.23
Composition and Function of Semen
What are the main components of semen?
Sperm, seminal vesicles secretion (60%), prostatic secretion (30%), vas deferens secretion (10%).
p.25
Mechanism of Erection
What type of nerves are responsible for initiating an erection?
Parasympathetic pelvic nerves.
p.19
Hormones Produced by the Testis
Where is small amounts of testosterone secreted in females?
From the ovary and the adrenal gland.
p.20
Biological Effects of Androgens
What are 17-ketosteroids in terms of androgen activity?
They are weak androgens, accounting for about 20% of testosterone activity.
p.12
Maturation and Storage of Sperm
What prevents sperm from achieving final motility in the epididymis?
Several inhibitory proteins in the epididymal fluid.
p.21
Biological Effects of Androgens
What effect does testosterone have on kidney size?
It increases the size of the kidneys.
