Comprehensive Reproductive System: Anatomy, Physiology, and Functions in Animals

What is the primary function of the reproductive system?

Preservation of species, not self.

What are the two main components of reproduction?

Spermatogenesis (formation of spermatozoa) and Oogenesis (formation of ova).

What is the role of the male reproductive system?

To produce male sex hormones, develop spermatozoa, and deliver spermatozoa.

Where are the testes located?

In the scrotum.

What is spermatogenesis?

The formation of spermatozoa that occurs in the seminiferous tubules.

What is the primary androgen produced by the testes?

Testosterone.

What are the three parts of a spermatozoon?

Head, midpiece, and tail.

What does the acrosome of a spermatozoon contain?

A type of digestive enzyme to help penetrate the ovum.

What is the function of the midpiece of a spermatozoon?

It contains mitochondria that provide ATP for sperm function.

What is cryptorchidism?

The failure of the testes to descend into the scrotum.

What is the role of the scrotum?

To house the testes and help regulate their temperature.

How does the cremaster muscle help the testes?

It adjusts the position of the testes based on temperature.

What does the spermatic cord contain?

Blood vessels, nerves, lymphatics, and the vas deferens.

What are the two layers of connective tissue surrounding the testes called?

Visceral vaginal tunic and Parietal vaginal tunic.

What is the function of Sertoli cells?

To provide nutrition and protection to immature sperm cells.

What is the epididymis?

A flat ribbon-like structure where spermatozoa complete their maturation.

What is the pampiniform plexus?

A mesh of blood vessels that helps cool the blood to the testes.

What happens to spermatozoa after they are formed?

They move to storage through the efferent ducts to the epididymis.

What is the function of the capsule surrounding the testes?

To protect and support testicular contents.

What are immature sperm cells called?

Spermatoids.

What hormone stimulates the creation of androgens in the testes?

LH (Luteinizing Hormone), also known as interstitial cell stimulating hormone.

What is the primary purpose of the reproductive system?

To ensure the continuation of the species.

What is the function of the epididymis?

It connects efferent ducts to the vas deferens and is where spermatozoa enter.

What is the main function of the vas deferens?

It connects the epididymis with the urethra for ejaculation.

What are the two functions of the urethra in males?

Carries urine from the urinary bladder and carries semen out during ejaculation.

What role do accessory reproductive glands play?

They produce components of semen, including alkaline fluids, fructose, and prostaglandins.

What is the function of the seminal vesicles?

They contribute to semen but are not present in dogs and cats.

What is benign prostate hyperplasia (BPH)?

An overgrowth of the prostate that can cause urinary problems, common in unaltered animals.

What is the role of the bulbourethral gland?

It secretes mucinous material to clear and lubricate the urethra for semen passage.

What are the three main parts of the penis?

Roots, body, and glans.

What is the function of the glans of the penis?

It is the distal free end of the penis, containing many nerves and is sensitive to stimulation.

What is the prepuce?

A sheath of skin that encloses the penis when not erect.

What is unique about the dog's penis structure?

It includes a bone (os penis) and an erectile structure that locks the male to the female during mating.

What is the function of the ovaries?

They produce ova and hormones, including estrogens and progestins.

What is oogenesis?

The process of ova production in the ovaries.

What hormones are produced by the corpus luteum?

Progestins, primarily progesterone, which helps prepare the uterine lining for implantation.

What triggers ovulation in the ovarian cycle?

A peak in luteinizing hormone (LH) levels.

What are the oviducts also known as?

Fallopian tubes or uterine tubes.

What is the role of the infundibulum in the female reproductive system?

It catches the ova released during ovulation and guides it to the oviduct.

What is an ectopic pregnancy?

A condition where a fertilized ovum implants outside the uterus, often in the abdominal cavity.

What is the difference between uniparous and multiparous animals?

Uniparous animals give birth to one offspring at a time, while multiparous animals can have multiple offspring.

What is the significance of estrogen in the female reproductive system?

It prepares the body for breeding and pregnancy.

What are the broad ligaments in the female reproductive system?

They suspend the ovaries, oviducts, and uterus, containing blood vessels and nerve supply.

What happens during the ovarian cycle when FSH is released?

It stimulates an oocyte to begin maturation and triggers estrogen release.

What is the function of prostaglandins in semen?

They can create minor uterine contractions to help move semen further up the uterine tract.

What is the primary function of the female reproductive system?

Production of sex hormones, ova, housing fertilized ovum, and providing an environment for embryo development.

What is the role of fructose in semen?

It provides sugar to build ATP for spermatozoa.

What is the significance of the spongy erectile tissue in the penis?

It fills with blood during an erection, allowing for vaginal insertion.

What is the primary function of the uterus?

Where the fertilized ovum implants, grows, and develops.

What happens to the uterus after parturition?

It returns to its original size.

What is the role of the uterus in pregnancy?

It forms part of the placenta and acts as a life-supporting system for the developing offspring.

What is the structure of the uterus?

A hollow muscular organ, usually Y-shaped in most domestic animals.

What are the three layers of the uterus?

Endometrium (innermost), Myometrium (middle), and Perimetrium (outermost).

What is the function of the cervix?

A muscular sphincter that seals the uterus from the outside world.

When does the cervix open?

During heat (estrus) and parturition.

What is pyometra?

A pus-filled uterus resulting from infection.

What is the function of the vagina?

It receives the penis during breeding and acts as the birth canal during parturition.

What are the three main parts of the vulva?

Vestibule, Clitoris, and Labia.

What is the difference between estrus and estrous?

Estrus refers to the heat period when a female is receptive to mating; estrous is the entire cycle from one heat to the next.

What is polyestrous?

Animals that cycle continuously throughout the year if not pregnant.

What characterizes the proestrous stage?

Period of follicular development and preparation of the reproductive tract for pregnancy.

What occurs during the estrus stage?

The peak of estrogen levels and sexual receptivity in females.

What happens during metestrus?

The corpus luteum develops and produces progesterone.

What is diestrus?

The stage when the corpus luteum is at its maximum size, and if not pregnant, it degrades.

What is anestrus?

A period of temporary ovarian inactivity.

What is a zygote?

A fertilized ovum made of male and female pronuclei.

What are the stages of development after fertilization?

Cleavage, Morula stage, and Blastocyte stage.

What is implantation?

The process where the blastocyte attaches to the uterine wall to develop into an embryo.

What is the role of the placenta?

To provide nutrients and remove waste for the developing offspring.

What is the primary reason for a female's high caloric intake during pregnancy?

To maintain herself and her babies.

What is the function of the placenta?

It grows with the offspring to meet its needs.

What connects the baby to the placenta?

The umbilical cord.

What does the umbilical cord contain?

Arteries, a vein, and the urachus.

What is the purpose of the urachus?

It serves as a drainage tube from the bladder to the placenta.

What type of blood do umbilical arteries carry?

Deoxygenated blood away from the offspring to the placenta.

What type of blood do umbilical veins carry?

Oxygen and nutrient-rich blood from the placenta to the offspring.

What is the amnion?

The layer immediately around the offspring forming the amniotic sac.

What fills the amniotic sac?

Amniotic fluid.

What surrounds the amniotic sac?

The allantois.

What is the chorion?

The layer outside the allantois that attaches to the uterine lining.

What is diffuse placental attachment?

Spread out, loose attachments in various points through the lining of the uterus.

What is cotyledonary placental attachment?

Numerous small tight attachments called placentomes, difficult to detach at birth.

What is zonary placental attachment?

A belt-shaped zone of attachment, easy to detach at birth.

What is discoid placental attachment?

A discrete disc connection, can have retained placenta.

What is gestation?

The period of pregnancy, separated into trimesters.

What occurs during the first trimester of gestation?

Development of the embryo and supporting placenta.

What occurs during the second trimester of gestation?

Development of all organs and tissues.

What occurs during the third trimester of gestation?

Growth of the offspring and transition to being free-living.

What is parturition?

The birth process.

What triggers parturition?

Unknown, likely related to the weight of the offspring, uterus, and hormonal changes.

What are the three stages of labor?

1. Uterine contractions, 2. Delivery of newborn, 3. Delivery of afterbirth/placenta.

What do mammary glands produce?

Colostrum and milk.

What is colostrum?

A pre-milk substance high in protein, lipids, and immunoglobulins for passive immunity.

What is the role of oxytocin in lactation?

It stimulates milk let down by causing contraction of myoepithelial cells.

What is the streak canal?

The passage from the teat cistern to the outside.

What is the significance of the California mastitis test?

It tests each quadrant of the udder for infection.