1. Reproductive System

2. Reproductive hormones
Testosterone
from testes
sperm production & sex characteristics
Estrogen
from ovaries
egg production, preparing uterus for fertilized egg & sex characteristics

3. Male reproductive system
Sperm production
over 100 million produced per day!
~2.5 million released per drop!

4. seminiferous tubule
sperm
spermatocytes

5. Male reproductive system
Testes & epididymis
sperm production & maturation
Glands
seminal vesicles, prostate, bulbourethal (Cooper’s Gland)
produce white seminal fluid-nutrient-rich

6. Male reproductive system
Testicles
produces sperm & hormones
Scrotum
sac that holds testicles outside of body- maintains lower temperature
Epididymis
where sperm mature- 18 hrs
Vas Deferens
tubes for sperm to travel from testes to penis
Prostate, seminal vesicles, Cowper’s (bulbourethal) glands
nutrient rich fluid to feed & protect sperm

7. Testis and Spermatogenesis

8. Spermatozoa
Head contains nucleus- contains enzymes that help the sperm enter the egg.
body and tail allow movement
Mitochondria- provides ATP for movement

9. Female reproductive system

10. Female reproductive system
Ovaries- have 2
produces eggs & hormones- estrogen & progesterone
Uterus
Site for fetal development, nurtures fetus; lining builds up each month- menstruation- shedding of the lining of the uterus.
Fallopian tubes- 2
tubes for eggs to travel from ovaries to uterus
Fertilization occurs in the fallopian tubes
Cervix
(separates vagina from uterus) opening to uterus, dilates 10 cm for birthing baby
Vagina
birth canal for birthing baby

11. Female reproductive system

12. Egg maturation in ovary
releases progesterone
maintains uterus lining
produces estrogen

13. Menstrual cycle Controlled by interaction of 4 hormones FSH & LH
estrogen
progesterone
FSH
ovulation = egg release
egg development
corpus luteum
estrogen
progesterone
lining of uterus
days 7 14 21 28

14. Female reproductive cycle
Feedback
Female reproductive cycle
egg matures &
is released (ovulation)
builds up uterus lining
estrogen
ovary
corpus luteum
progesterone
FSH & LH
fertilized egg (zygote)
maintains uterus lining
HCG
yes
pituitary gland
corpus luteum
pregnancy
GnRH no
progesterone
corpus luteum breaks down
progesterone drops
menstruation
maintains uterus lining
hypothalamus

15. Female hormones FSH & LH Estrogen Progesterone
stimulates egg development & hormone release
peak release = release of egg (ovulation)
Estrogen
stimulates growth of lining of uterus
decreasing levels causes menstruation
Progesterone
stimulates blood supply to lining of uterus

16. Fertilization

17. Fertilization- process where sperm enters and fertilizes egg (ovum)- resulting in the formation of a zygote

18. Sex Determination in Mammals

19. Twins Identical Twins- ONE fertilization
Zygote splits into two with each being identical to one another

20. Fraternal Twins- TWO fertilizations
Two different zygotes (different egg and sperm)

21. Siamese Twins- identical twins whose bodies fail to fully separate- and stay joined together

23. Placenta & umbilical cord
Allows for nutrients and gases to be exchanged between mom and child
Food & gases diffuse across blood vessels

24. Human fetal development
4 weeks
7 weeks

25. Human fetal development
10 weeks

26. Human fetal development
12 weeks
20 weeks

27. Human fetal development
The fetus just spends much of the 2nd & 3rd trimesters just growing
…and doing various flip-turns & kicks inside amniotic fluid
Week 20

28. Human fetal development
24 weeks (6 months; 2nd trimester)
fetus is covered with fine, downy hair called lanugo. Its skin is protected by a waxy material called vernix

29. Human fetal development
30 weeks (7.5 months)
umbilical cord

30. Getting crowded in there!!
32 weeks (8 months)
The fetus sleeps 90-95% of the day & sometimes experiences REM sleep, an indication of dreaming

31. positive feedback
Birth

32. Birth (36 weeks) Intestine Placenta Umbilical cord Wall of uterus
Bladder
Cervix
Vagina

33. And you think 9 months of Biology is hard!
The end of the journey!
And you think 9 months of Biology is hard!

34. Harmful Environmental Factors
Embryo’s inherited genes can cause diseases
Mutations- changes in DNA (DNA makes up chromosomes)
Mother’s exposure to harmful environmental factors such as DRUGS, POOR DIET, ALCOHOL, TOBACCO can cause developmental problems and learning disabilities
Sexually Transmitted Diseases (STDs)- diseases passed on from person to person through sexual contact
AIDS, Chlamydia, Syphilis

35. Let’s Practice!
1. Which statement about the gametes represented in the diagram below is correct?
They are produced by females.
They are fertilized in an ovary.
They transport genetic material.
They are produced by mitosis.

36. 2. Base your answer on your knowledge of biology and on the diagrams
2. Base your answer on your knowledge of biology and on the diagrams. Testosterone is produced by
structure A
structure B
structure C
structure D

37. 3. Base your answer to this question on the diagram below, which represents some stages in the development of an embryo, and on your knowledge of biology. The arrow labeled X represents the process of
meiosis
recombination
differentiation
cloning

38. 4. Base your answer on the diagram and your knowledge of biology
4. Base your answer on the diagram and your knowledge of biology. Gamete cells are produced within
structures A and J
structures E and G
structures B and I
structures D and H

39. 5. The diagram represents some stages in the development of an embryo
5. The diagram represents some stages in the development of an embryo. Which stage represents a zygote?
stage A
stage B
stage C
stage D

40. 6. The primary function of structure X is to
produce energy needed for sperm to move
provide food for the sperm to carry to the egg
produce and store urine
form gametes that may be involved in fertilization

41. 7. Although all the body cells in an animal contain the same hereditary information, they do not all look and function the same way.  The cause of this difference is that during differentiation
embryonic cells use different portions of their genetic information
the number of genes increases as embryonic cells move to new locations
embryonic cells delete portions of the chromosomes
genes in embryonic cells mutate rapidly

42. 8. Which hormone has the lowest concentration on which day?
hormone A on day 4
hormone B on day 2
hormone C on day 12
hormone D on day 20

43. 9. During which five-week period did the fetal mass increase at the greatest rate?
weeks 10–15
weeks 15–20
weeks 25–30
weeks 30–35

44. 10. Human egg cells are most similar to human sperm cells in their
degree of motility
amount of stored food
chromosome number
shape and size

45. 11. The process of meiosis formed
cell 1, only
cells 1 and 2
cell 3, only
cells 2 and 3

46. 12. Heavy cigarette smoking and the use of alcohol throughout pregnancy usually increase the likelihood of
the birth of twins
the birth of a male baby
a baby being born with a viral infection
a baby being born with medical problems

47. 13. A large number of sperm cells are produced by males every day
13. A large number of sperm cells are produced by males every day. This large number of sperm cells increases the chance that
at least one sperm cell will be reached when the eggs swim toward the sperm cells in the ovary
several sperm cells will unite with an egg so the fertilized egg will develop properly
some of the sperm cells will survive to reach the egg
enough sperm cells will be present to transport the egg from where it is produced to where it develops into a fetus

48. 14. In 1993, there were only 30 panthers in Florida
14. In 1993, there were only 30 panthers in Florida. They were all closely related and many had reproductive problems. To avoid extinction and restore health to the population, biologists introduced 8 female panthers from Texas. Today, there are more than 80 panthers in Florida and most individuals have healthy reproductive systems. The success of this program was most likely due to the fact that the introduced females
produced more reproductive cells than the male panthers in Texas
solved the reproductive problems of the species by asexual methods
increased the genetic variability of the panther population in Florida
mated only with panthers from Texas

49. 15. Exposure to radiation or certain chemicals could alter the genetic information in the gametes that form in structure A B C D

50. 16. Which event would most probably result in the production of fraternal twins?
One egg is fertilized by two sperm cells.
Two egg cells are fertilized by one sperm cell.
Two egg cells are each fertilized by separate sperm cells.
Two eggs develop without fertilization.

51. 17. Compared to human cells resulting from mitotic cell division, human cells resulting from meiotic cell division would have
twice as many chromosomes
the same number of chromosomes
one-half the number of chromosomes
one-quarter as many chromosomes

52. 18. Which phrase best describes a process represented in the diagram below?
a zygote dividing by mitosis
a zygote dividing by meiosis
a gamete dividing by mitosis
a gamete dividing by meiosis

53. 19. A cell with a diploid chromosome number of 12 divided two times, producing four cells with six chromosomes each. The process that produced these four cells was most likely
internal fertilization
external fertilization
mitotic cell division
meiotic cell division

54. 20. Which structure is correctly paired with its function?
A - releases estrogen and progesterone
B - produces and releases the egg
C - provides the usual site for fertilization
D - nourishes a developing embryo