How many chromosomes do body and sex cells each have

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Chapter 18

• How many chromosomes do body and sex cells each
  have?
• Understand the anatomy of both the male and
  female.
• What are the 3 parts of a sperm?
• How do hormones play a role in the male?
• Explain the ovarian and uterine cycles.
• Where do fertilization and implantation occur?
• What is infertility? What can cause this?

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DNA in body and sex cells
16.1 Human life cycle

• Body cells
• Each body cell has ____chromosomes within the
  nucleus
• Cells that have pairs of chromosomes are called
  ________ (2N)
• Sex cells
• Gametes (egg and sperm) have only ___ chromosomes
  in their nuclei
• Cells that have only 1 of each pair of
  chromosomes are called __________ (N)
• During fertilization a sperm and egg combine to
  form a ________.

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Mitosis and meiosis
16.1 Human life cycle

• Which one makes an exact copy of itself?
• Which one occurs in body cells? Sex cells?
• How do the chromosomes compare in the cells that
  result from meiosis?
• Why does mitosis occur?
• What is crossing over?

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Male anatomy
16.2 Male reproductive system

• Scrotum
• Testes
• Epididymis
• Vas deferens
• Urethra
• 3 glands
• Penis

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Male anatomy Scrotum and testes
16.2 Male reproductive system

• Scrotum
• Sacs that hold the testes
• Help regulate the temperature of the testes
• Testes
• Paired organs that produce sperm and male sex
  hormones
• Composed of seminiferous tubules where sperm are
  being produced
• Epididymis
• Sperm mature and are stored here

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Male anatomy Scrotum and testes
16.2 Male reproductive system
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Sperm anatomy
16.2 Male reproductive system

• 3 parts
• Head acrosome enzymes
• Middle piece mitochondria
• Flagella movement

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Male anatomy Vas deferens and urethra
16.2 Male reproductive system

• Vas deferens
• Transports sperm to the urethra
• Urethra
• Transports sperm ( urine) out of the body

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Male anatomy 3 glands that contribute to semen
16.2 Male reproductive system

• Seminal vesicles produce a sugary fluid that
  provide energy for the sperm and an alkaline
  fluid
• Prostate gland produces an alkaline fluid to
  help buffer the acidic pH
• Bulbourethral glands produce mucus and an
  alkaline fluid

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Male anatomy Penis
16.2 Male reproductive system

• Glans penis
• Intensely sensitive tip of the penis usually
  covered by foreskin
• Circumcision
• Erectile dysfunction (impotency) occurs when the
  erectile tissue does not expand enough to
  compress the veins

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Hormonal regulation in males
16.2 Male reproductive system

• Gonadotropin-releasing hormone (GnRH) secreted
  by the _______________ to control release of
  other hormones
• Follicle-stimulating hormone (FSH) secreted by
  the __________ to promote the production of sperm
• Luteinizing hormone (LH) secreted by the
  __________ to control the production of
  testosterone
• Testosterone important for normal development
  and functioning of the male reproductive organs

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Hormonal regulation in males
16.2 Male reproductive system
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Female anatomy
16.3 Female reproductive system

• Genital tract
• Ovaries
• Oviducts
• Uterus
• Cervix
• Vagina

• External genitals (vulva)
• Labia major
• Labia minor
• Mons pubis
• Clitoris

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Female anatomy Genital tract
16.3 Female reproductive system

• Ovaries produce eggs and sex hormones
• Oviducts moves eggs and normal site of
  fertilization
• Uterus normal site of implantation and fetal
  development
• Cervix opening to the uterus that can dilate
  during childbirth
• Vagina birth canal

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Female anatomy Genital tract
16.3 Female reproductive system
16
Female anatomy External anatomy
16.3 Female reproductive system

• Labia major 2 large folds of fatty skin
• Labia minor 2 small folds just inside the labia
  major that contain the opening to the urethra and
  vagina
• Mons pubis fatty skin covered in coarse hair
• Clitoris erectile organ

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The ovarian cycle The ovary
16.4 Female hormone level

• Contains many follicles each containing an
  immature egg (oocyte)
• At birth a female has 300,000-400,000 follicles
• How many of these will mature?
• When will these mature?
• Ovulation is the monthly release of an oocyte
  from the ovary when a follicle ruptures

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Anatomy of the ovary
16.4 Female hormone level
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The ovarian cycle
16.4 Female hormone level
The uterine cycle

• Follicular phase
• FSH
• Estrogen
• Luteal phase
• LH
• Progesterone
• If pregnancy does not occur menstruation begins

• Menstruation
• Proliferation
• Ovulation
• Secretion

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Hormones in the ovarian and uterine phase
16.4 Female hormone level
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Fertilization and Pregnancy
16.4 Female hormone level

• Fertilization union of a sperm and egg nucleus
  normally in the oviduct to form a zygote
• Pregnancy begins with implantation usually 6
  days after fertilization

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What is infertility and what causes it?
16.5 Control of reproduction

• This is the inability to achieve pregnancy after
  one year of regular, unprotected intercourse
• A few causes
• Overweight females
• Low sperm count
• Blocked oviducts
• Endometriosis

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What are your options if you are infertile?
16.5 Control of reproduction

• Adoption legal custody of a non-biological
  child
• Assisted reproductive technologies
• Artificial insemination
• In vitro fertilization (IVF)
• Gamete intrafallopian transfer (GIFT)
• Surrogate mother
• Human cloning???

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Bioethical focus Should cloning be used to treat
infertility?
16.5 Control of reproduction

• Pros?

• What is the current legislation in Iowa?

• Cons?