The ova can only carry the x chromosome while sperm

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- The Ova can only carry the X chromosome , while Sperm can carry either the X or Y chromosome . - The Reproductive System: The X Chromosome: - The X chromosome carries a sizable amount of genetic information and mutations in this genes can cause sex linked (X-linked) disorders - Males are termed Hemizygous with respect to many of the genes on the X chromosome because they only have one copy. Therefore a male with a disease causing allele on the unpaired part of the X chromosome will express that allele - Females are termed Homozygous or Heterozygous with respect to genes on the X chromosome because females will express these disorders far less frequently than males since they have two copies. - Most X-linked disorders are recessively inherited and females carrying a diseased allele on an X chromosomes but not exhibiting the disease are said to be carriers - The Reproductive System: The Y Chromosome: - The Y chromosome carries very little genetic information, but one notably gene on the Y chromosome is the SRY (sex-determining region Y) gene. - This gene codes for the transcriptional factors that initiate testis differentiation and thus the formation of the male gonads. - Therefore in the absence of the Y chromosome, all zygotes will be female and in the presence of the Y chromosome a zygote will be a male - The Male Reproductive Anatomy: Pathway of Sperm - In males the primitive gonads develop into the testes and the testes have two functional components: The Seminiferous Tubules and the Interstitial Cells of Leydig - Sperm are produced in the Seminiferous Tubules in the testes, where they are nourished by the Sertoli Cells
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- While the Interstitial Cells of Leydig in the testes secrete testosterone and other male sex hormones (androgens) - The testes are located in the scrotum, an external pouch that hangs below the penis, and is in a position that allows it to maintain a temperature 2 ° to 4 °C lower than the body - The Male Reproductive Anatomy: Pathway of Sperm - As sperm are formed they are passed to the epididymis , where their flagella gain motility. They are then stored here until ejaculation - During ejaculation, sperm travel through the vas deferens and enter the ejaculation duct at the posterior edge of the prostate gland. - The two ejaculation ducts then fuse to form the urethra , which carries sperm through the penis as they exit the body. - Pathway of the sperm through the male reproductive system abbreviation: SEVE(N) UP: Seminiferous tubules → Epididymis → Vas Deferens → Ejaucylation Duct → (Nothing) → Urethra → Penis - The Male Reproductive Anatomy: Seminal Fluids - As sperm passes through the MRT, they are mixed with seminal fluid, which is produced through a combined effort of: the seminal vesicles, prostate gland, & bulbourethral gland - Seminal Vesicles : Contribute fructose to nourish sperm and produce an alkaline fluid - Prostate Gland: Also produces an alkaline fluid. Both fluids help sperm survive in the relatively acidic female reproductive tract - Bulbourethral (Cowper’s) Gland: Produces a clear viscous fluid that cleans out any remnants of urine and lubricates urethra during
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