TOPIC 2 - MALE AND FEMALE REPRODUCTIVE SYSTEM

• Animal Development

  • the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals
  • as an animal embryo develops, its cells divide, grow, and migrate in specific patterns to make a more and more elaborate body
• Gametogenesis

  • process by which gametes are produced in an organism
  • occurs when a haploid cell (n) is formed from a diploid cell (2n) through meiosis
  • production of gametes
• Spermatogenesis - process of developing male gametes, known as sperm within the testes.
• Oogenesis - the production or development of an ovum.
• Fertilization

  • process in which gametes fuse to form a diploid zygote
  • egg and sperm are haploid, which means they each contain one set or chromosomes
  • combine their genetic material to form a zygote that is diploid, having two sets of chromosomes
• Cleavage

  • rapid succession of cell division
  • doubling with each division
  • each cell smaller than zygote
• Cleavage

  • Blastula - hollow ball of cells with a large cavity surrounded by one or more layers of cells
  • Blastocoel - fluid filled cavity forms at the center of the embryo
• Gastrulation - a stage of development involving morphogenic movements of the cells to produce a gastrula with distinct germ layers

  • Ectoderm - forms the outer layer of the gastrula
  • Endoderm - lines the embryonic digestive tract
  • Mesoderm - partly fills the space between the endoderm and ectoderm
• Organogesis

  • different germ layers differentiate into specific organ systems
  • process of Gastrulation that leads to the formation of the three germ layers that give rise during further development to the different organs in the animal body
  • organs develop from the germ process through the process of differentiation
• Monozygotic Twins (Identical Twins) - twins that result from a single fertilized egg.
• Dizygotic Twins (Fraternal Twins) - twins that develop from two different eggs and sperm.
• Penis

  • the organ by which the sperm is introduced to the female
  • contains spongy tissue that becomes turgid and erect when filled with blood
• Erectile Tissues

  • Corpus spongiosum - the mass of spongy tissue which surrounds urethra and involves in erection by allowing rushing of blood into it
  • Corpus cavernosa - one of a pair of a sponge-like regions of erectile tissue which contains most of the blood in the penis during penile erection
• Urethra - tube within the penis that conveys semen out of the body during ejaculation.
• Glans - the rounded, highly sensitive head of the penis.
• Prepuce - a fold of skin, covering the head of the penis.
• Scrotum

  • sac of skin formed from the lower part of the abdominal wall
  • it keeps the testes at a temperature slightly cooler than body temperature
• Testis (plural Testes) - the two oval shaped male organs that produce sperm and hormone testosteron.
• Testosterone - the primary male sex hormone.
• Each testis is made up of tightly coiled structures called seminiferous tubules.
• Epididymis

  • tightly coiled tubes against the testicles
  • acts as maturation and storage place for sperm
• Vas Deferens (Ductus Deferens)

  • a thin tube that starts from the epididymis tot he urethra in the penis
  • they transport sperm from the epididymis in anticipation of ejaculation
• Accessory Glands - these glands produce nourishing fluids for the sperms that enter the urethra.

  1. Seminal Vesicles
  2. Prostate Gland
  3. Bulbourethral Glands
• Seminal Vesicles - sac-like structures attached to the vas deferens an one side of the bladder, it produces a sticky yellowish fluid that contains fructose.
• Prostate Gland - surround the ejaculatory ducts at the base of the urethr, just below the bladder, it’s responsible for making the production of semen.
• Semen - a liquid mixture of sperm cells, prostate fluid and seminal fluid.
• Bulbourethral Glands(Cowper’s Gland) - two small glands located on the sides of the urethra just below the prostate gland, it produce a clear, slippery fluid that empties directly into the urethra.
• Emission - the discharge of semen from the urethra.

  Ejaculation - forceful expulsion of the semen from the urethra caused by contraction of muscles in the penis.
• Cervix - the opening of the uterus that allows the fetus to pass through during labor, it’s the lower portion or neck of the uterus.
• Cervical Mucus - mucus that is produced by the cervix that provides lubrication and sperm transport during sexual intercourse.
• Vagina

  • muscular, rigged sheath connecting the external genitals to the uterus
  • functions as a two-way street, accepting the penis and sperm during intercourse
• External Genetalia

  • Vulva - runs from the pubic area downward to the rectum.
  • Labia majora (greater lips) - part around the vagina containing two glands(Bartholin’s glands) which helps lubrication during intercourse.
  • Labia minora (lesser lips) - thin hairless ridges at the entrance of the vagina, which joins behind and in front.
  • Clitoris - small pea-shaped structure.
• Ovaries (female gonads)

  • produce eggs(ova)
  • produce hormones: Estrogen and Progesterone
• Fallopian Tubes (Uterine Tubes)

  • stretch from the uterus to the ovaries
  • measures about 8 to 13 cm in length
  • the ends lies next to the ovaries feather into ends called fimbria
  • where fertilization usually occurs
• Uterus

  • pear-shaped muscular organ in the female reproductive tract
  • the organd grows from 10 to 20 times its normal size during pregnancy
  • main body consists of a firm outer coat of muscle(myometrium) and an inner lining vascular, gladular material(endometrium)
• Endometrium

  • innermost layer as a lining for the uterus
  • during pregnancy, the blood vessels in the endometrium further increases in size and number, forming the placenta
  • Placenta - supplies the oxygen and nutrition to the embryo and fetus.