Sex Cell Development In Males

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Sex Cell Development In Males

• Sex cells (also called gametes) are produced
  through the process of meiosis.
• Gametes are produced in the reproductive organs
  called gonads.

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• Male gonads are called testes. The gametes
  produced by males are called sperm.
• Each sperm cell is built for motion they are
  very streamlined and carries little excess weight.

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• This means the sperm has very limited cytoplasm.
• Although this is good for a cell that needs to
  move, it also means the sperm cell has very
  limited energy., and dies within a few days.

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• Sperm is produced in the testes. These are stored
  in the scrotum which is the sac that houses the
  testes.
• This is located outside of the body, because a
  cooler temperature is required for the production
  of sperm.

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• The gametes are then stored in the epididymus.
• The prostate gland and seminal vesicle are glands
  which produce a thick liquid, rich in sugars, for
  the sperm to swim in.

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• The combination of sperm cells plus liquid is
  called semen.
• During ejaculation, semen travels through the vas
  deferens and out the urethra.

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• A hormone is a chemical messenger sent by the
  braid. Hormones are used to trigger many things
  in the body.
• In males, the primary sex hormone is
  testosterone, which stimulates sperm development.

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• Two other hormones are important in sperm
  development.
• These are lutenizing hormone, hormone (LH), and
  follicle stimulating hormone (FSH).

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• Development in male sex cells continues
  throughout the lifetime.
• Men over the age of 90 have been known to father
  children!!!

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• SEX CELL DEVELOPMENT IN FEMALES
• Female sex cells are also produced in the
  __gonads_____. In females, the gonads are called
  __ovaries_____. The female gametes are called
  __ovum_______ or eggs. The female reproductive
  system is more complicated than that of the male,
  because it has an extra duty - ___to house a
  developing fetus_________________________.

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• The egg is much ___larger___ than the sperm, and
  is packed with ___nutrients______ so that when
  fertilized it can divide quickly. It is capable
  of building a _barrier_______ after fertilization
  to prevent more sperm from entering. Unlike
  males who produce __millions______ of sperm cells
  each day, the female develops only __1____ egg at
  a time. Each female is born with a limited
  number of eggs, which can then mature or die.

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Approximately once per month, the ovary wall
bursts and an egg is released into the __oviduct_
or fallopian tube. The release process is called
__ovulation___. The egg then moves toward the
__uterus________, the organ responsible for
nourishing an embryo if it grows. Each ovulation
cycle, the uterus grows a thick lining called the
___endometrium____.
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• If the egg is ___fertilized___ by a sperm cell
  while moving through the ____fallopian tube___,
  it will begin to divide by mitosis, becoming an
  embryo and embedding in the endometrium. If the
  egg is not fertilized, the endometrium is she in
  a process called ___menstruation___.

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• There are two main hormones involved in the
  female reproductive system - __estrogen________
  which tells the endometrium to thicken in
  preparation, and ____progesterone_______ which
  prohibits further ovulation and trigger
  menstruation.

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