Week 26 / Reproductive system 1 & 2 Flashcards
Q1: What is reproduction?
A1: Reproduction is the union of male and female gametes (reproductive or germ cells), each with half a set of chromosomes, to form a new individual with a full, unique set of chromosomes.
Q2: How are male and female body systems similar?
A2: All body systems are essentially identical in males and females, except for the reproductive system.
Q3: What is the role of the female reproductive system?
A3: The female reproductive system is equipped to nourish the offspring until it can survive independently in the external environment.
Q4: What is the purpose of the union of genetic material from two sexual partners?
A4: The purpose is to combine genetic material to create a new individual with a unique genetic makeup.
Q1: How many chromosomes do human somatic cells have?
A1: Human somatic cells have 46 chromosomes.
Q3: How are sex chromosomes identified?
Q4: What is the female genotype?
Q5: What is the male genotype?
A3: Sex chromosomes are identified as X and Y.
A4: The female genotype is XX.
A5: The male genotype is XY.
Q2: How are chromosomes distributed in somatic cells?
[how many pairs of somatic chromosomes,
how many pairs of sex chromies]
A2: Somatic cells have 22 pairs of somatic chromosomes and one pair of sex chromosomes.
Q6: Which chromosomes are contributed by the ovary?
A6: The ovary contributes X chromosomes.
Q7: Which chromosomes are contributed by sperm?
A7: The sperm contributes either X or Y chromosomes.
Q2: How are the mother’s and father’s germ cells divided?
A2: Germ cells undergo meiotic division.
Q1: What type of cells do parents have before sexual reproduction?
A1: Parents have diploid somatic cells with 46 chromosomes.
Q3: What is the chromosomal makeup of the ovum and sperm after meiosis?
[type of cells , number of chromosomes]
A3: The ovum and sperm are haploid, each with 23 chromosomes.
Q4: What happens during fertilization?
A4: The haploid ovum and sperm combine to form a diploid fertilized ovum with 46 chromosomes.
Q5: How does the fertilized ovum develop into an offspring?
A5: The fertilized ovum undergoes mitosis, resulting in offspring with diploid somatic cells (46 chromosomes).
Q1: What are the main organs of the male reproductive system? [4]
A1: Testes, ducts, glands, and supporting structures.
Q2: What are the ducts in the male reproductive system? [4]
A2: Epididymis, ductus deferens, ejaculatory ducts, and urethra.
Q1: What do the testes produce?
A1: The testes produce sperm and the male sex hormone testosterone.
Q3: What glands are part of the male reproductive system? [3]
A3: Seminal vesicles, prostate, and bulbourethral glands.
Q4: What are the supporting structures in the male reproductive system?
A4: Scrotum and penis.
Q4: What is the function of the penis?
[what contains ,
what does ^^ it do]
A4: The penis contains the urethra, which serves as a passageway for the ejaculation of semen and the excretion of urine.
Q2: What is the role of the ducts in the male reproductive system? [3]
A2: The ducts transport, store, and assist in the maturation of sperm.
Q3: What do the accessory sex glands secrete?
A3: The accessory sex glands secrete most of the liquid portion of semen.
Q1: What is the scrotum?
A1: The scrotum is a sac of loose skin, fascia, and smooth muscle (dartos muscle) that supports the testes.
Q2: How is the scrotum divided?
A2: The scrotum is divided into two pouches by a septum, with each pouch supporting one testis.
Q3: Why is temperature regulation important for the testes?
A3: Sperm production requires a temperature 2-3°C below body temperature.
Q4: How does the scrotum adjust the temperature of the testes?
A4: The scrotum raises or lowers the testes to adjust their temperature.
Q5: What is the cremaster muscle?
A5: The cremaster muscle consists of small skeletal muscle bands that descend as an extension of the spermatic cord to surround the testes and help regulate their position.
Q1: What are the testes?
A1: The testes are paired oval glands.
Q2: Where do the testes develop in the embryo?
[where do they develop
where do they descend ]
A2: The testes develop on the embryo’s posterior wall and descend into the scrotum.
Q4: What are the two main functions of the testes?
A4:
Production of sperm, the male gametes that carry genetic material and can fertilize an egg.
Secretion of steroid hormones, primarily testosterone, which supports normal sperm production and full masculine development.
Q3: When do the testes descend into the scrotum?
A3: The descent begins in the 7th month of embryonic development.
Q1: How many lobules is each testis divided into?
A1: Each testis is divided into 250-300 lobules (segments).
Q2: What do the lobules contain?
A2: Each lobule contains 2-3 coiled tubes called seminiferous tubules.
Q3: What happens at the apex of each lobule?
A3: At the apex of each lobule, the seminiferous tubules join and pass into straight tubes called tubuli recti.
Q4: What do the tubuli recti form?
A4: The tubuli recti form the rete testis.
Q5: Where does the rete testis lead?
A5: The rete testis leads into the coiled epididymis.
Q1: What is the function of the outer smooth muscle in seminiferous tubules?
A1: The outer smooth muscle contracts to move sperm and fluid through the tubule.
Q2: What is the role of the inner epithelial cell layer (Sertoli cells) in seminiferous tubules?
A2: Sertoli cells control the formation and development of sperm.
Q3: What fills the lumen of the seminiferous tubules?
A3: The lumen is filled with fluid that serves as a medium for sperm development.
Q4: What lies between the seminiferous tubules?
A4: Connective tissue lies between the tubules, supporting them and containing clusters of Leydig cells (interstitial cells of Leydig).
Q5: What is the function of Leydig cells?
A5: Leydig cells synthesize and secrete testosterone and other androgens.
Q1: Where do Sertoli cells extend in the seminiferous tubules?
A1: Sertoli cells extend from the basement membrane to the lumen of the tubules.
Q2: What barrier do Sertoli cells form?
A2: Sertoli cells form the blood-testis barrier.
Q3: What is the function of the blood-testis barrier?
A3: The blood-testis barrier isolates developing gametes from blood and prevents an immune response against the spermatogenic cell’s surface antigens.
Q4: How do Sertoli cells support spermatogenic cells?
A4: Sertoli cells support and protect developing spermatogenic cells and release sperm into the lumen.
Q5: What hormones are secreted by Sertoli cells?
Which hormones does it regulate the effects off?
A5: Sertoli cells secrete the hormone inhibin and regulate the effects of testosterone and follicle-stimulating hormone (FSH).
Q1: How does spermatogonium multiply?
A1: Spermatogonium with 2n=46 chromosomes multiplies by mitosis.
Q2: What does a primary spermatocyte contain?
[how many hormones does it contain]
A2: A primary spermatocyte contains 2n=46 chromosomes.
Q3: What happens during the first meiotic division?
A3: The first meiotic division produces two secondary spermatocytes, each with 23 double-stranded chromosomes.
Q4: What happens during the second meiotic division?
A4: The second meiotic division produces four spermatids, each with 23 single-stranded chromosomes.
Q5: How do spermatids develop into sperm?
A5: Each of the four spermatids develops into a sperm cell.
Q1: How many sperm are produced daily?
A1: Approximately 300 million sperm are produced each day.
Q2: What is the lifespan of sperm in the female reproductive tract?
A2: Sperm can survive for about 48 hours in the female reproductive tract.
Q3: What is the purpose of sperm’s structure?
A3: Sperm are adapted for reaching and fertilizing the egg.
Q4: What does the head of the sperm contain?
A4: The head contains DNA and the acrosome, which has enzymes for penetrating the egg.
Q5: What is the function of the middle part of the sperm?
A5: The middle part contains mitochondria, which produce ATP for energy.
Q6: What is the role of the sperm’s tail?
A6: The tail, a flagellum, is used for locomotion.
Q1: What are male sex hormones called?
A1: Male sex hormones are called androgens.
Q2: What is the primary male sex hormone?
A2: Testosterone is the primary male sex hormone and an androgen.
Q3: Where is testosterone primarily produced?
A3: Testosterone is mainly produced by the Leydig cells of the testes and, to a lesser extent, by the adrenal glands.
Q4: How is male sex hormone production characterized?
A4: Male sex hormone production is relatively constant with some diurnal variation.
Q5: What role do androgens play during fetal development?
[what are they responsible for?
what roles does it play?
which effects might it have?
]
A5: Androgens are responsible for fetal differentiation and the development of the male urogenital system, as well as some effects on the brain.
Q6: What happens to Leydig cells after birth?
A6: After birth, Leydig cells become quiescent until they are activated by gonadotropins during puberty.
Q7: What changes do androgens cause at puberty?
[2]
A7: At puberty, androgens cause the growth of sex organs and the development of secondary sex characteristics.
Q1: What role does testosterone play in spermatogenesis?
A1: Testosterone is required for the initiation and maintenance of spermatogenesis.
Q2: How does testosterone affect GnRH secretion?
A2: Testosterone decreases GnRH secretion via its action on the hypothalamus.
Q3: What effect does testosterone have on LH secretion?
A3: Testosterone inhibits LH secretion through direct action on the anterior pituitary gland.
Q4: How does testosterone influence male accessory reproductive organs?
A4: Testosterone induces the differentiation of male accessory reproductive organs and maintains their function.
Q5: What secondary sex characteristics does testosterone induce?
A5: Testosterone induces male secondary sex characteristics and opposes the action of estrogen on breast growth.
Q6: What is testosterone’s effect on growth?
A6: Testosterone stimulates protein anabolism, bone growth, and the cessation of bone growth.
Q7: What behavioral effect does testosterone have?
A7: Testosterone is required for sex drive and may enhance aggressive behavior.
Q8: How does testosterone affect the kidneys?
A8: Testosterone stimulates erythropoietin secretion by the kidneys.
Q1: What does the prostate gland secrete?
A1: The prostate secretes 30% of milky, slightly acidic seminal fluid containing an antibiotic to kill bacteria.
Q2: What is the function of seminal vesicles?
A2: Seminal vesicles secrete 60% of clear, alkaline seminal fluid containing:
Fructose sugar, ATP, and prostaglandins for normal sperm nutrition and function.
Chemicals for the coagulation of semen.
Q3: What do the bulbourethral glands (Cowper’s glands) secrete?
A3: The bulbourethral glands secrete clear, alkaline mucus to buffer and lubricate the urethra.
Q1: What structures does the penis contain?
A1: The penis contains the urethra, and its structure includes the root, body, and glans penis.
Q2: What is the function of the penis?
A2: The penis serves as a passage for semen and urine.
Q3: How many columns of erectile tissue are in the penis?
A3: The penis has three columns of erectile tissue:
Two dorsal columns called corpora cavernosa.
One ventral column surrounding the urethra called corpus spongiosum.
Q4: What is the glans penis?
A4: The glans penis is the distal end of the penis.
Q5: What covers the glans penis?
A5: The glans penis is covered by the foreskin (prepuce).
Q6: What is the surgical removal of the foreskin called?
A6: The surgical removal of the foreskin is called circumcision.
Q1: What is semen a mixture of?
A1: Semen is a mixture of sperm and seminal fluid.
Q2: What is the percentage contribution of each gland to semen production?
A2:
60% from seminal vesicles
30% from prostate
10% from bulbourethral glands
Q3: What is the appearance and pH of semen?
A3: Semen is slightly alkaline with a milky appearance and sticky texture.
Q4: What does semen contain?
A4: Semen contains nutrients, clotting proteins, and an antibiotic to protect sperm.
Q5: What is the typical volume of ejaculate?
A5: The typical ejaculate volume is 2.5 to 5 ml.
Q6: What is the normal sperm count?
A6: The normal sperm count is 50 to 150 million sperm per milliliter.
Q7: How many sperm are needed for fertilization?
A7: The actions of many sperm are needed for one to enter the egg.
Q8: What sperm count is considered sterile?
A8: A sperm count of less than 20 million per milliliter is considered sterile.
OPEN POWERPOINT FOR Factors contributing to ejaculation of
functional sperms
OPEN POWERPOINT FOR Factors contributing to ejaculation of
functional sperms
