1. Chapter 46- Animal Reproduction

2. Invertebrates- Fission (equal splitting), budding (unequal splitting), and fragmentation (lots of little pieces splitting off of parent)

3. Background Parthenogenesis- Egg/embryo formation without fertilization
Hermaphroditic- Animal can produce BOTH gametes (male & female)
External Fertilization- Usually produces a large amount of offspring, but many end up dying
Internal Fertilization- Fewer offspring, but have a better chance at surviving

5. Gonads Vertebrates (specifically humans) FEMALES
Female gonads are the ovaries. They are surrounded by follicles which have the eggs inside.
- Most of the eggs are formed before birth of the individual
- Ovulation- when an egg is released from a follicle. The egg will travel into the oviducts/fallopian tubes and then into the uterus (implantation into uterus depends on if it was fertilized in the oviducts)

7. Ovulation – Release of the egg from ovary (know the pathway!)
2) Travels through
Fallopian
tube
egg cell
1) egg released
from ovary
**Implantation or passes
out of body through
cervix, then vagina
ovary
3) Enters uterus
5 to 7 days to uterus
**Site of fertilization!

8. Gonads
MALES
Male gonads are the testes. Located outside of the abdominal cavity because the sperm need a slightly cooler temperature in order to develop properly).
- The sperm are produced in the testes and then are stored and mature in the epididymis (where sperm becomes motile and “grows up”) and then travel through the Vas deferens when exiting

10. GAMETES Gametogenesis- The formation of the gametes
Oogenesis- Formation of an egg from an oogonium. Meiosis will produce only one egg from the oogonium, the other two/three cells turn into polar bodies.

12. Gametogenesis
Spermatogenesis- Formation of sperm from spermatogonia. Meiosis will produce four sperm from one spermatogonia.

14. Pregnancy/Gestation
Gestation times vary depending on the animal (assume larger animals = longer gestation times)
*Humans = 9-10 months
Conception (fertilization) occurs in the Fallopian tube and cell division (mitosis) begins within 24 hours.

16. Fertilization Video 6 minutes: https://www. youtube. com/watch

18. After fertilization: Blastocyst (Fertilized Egg) uterine wall
Implantation

19. Process of development after Fertilization:
Zygote – fertilized egg (2n= sperm + ovum)
MITOSIS  Creates a hollow ball of cells called a Blastula (Blastocyst)  Implantation in uterus wall (now called an “EMBRYO”  Gastrulation occurs (indentation of internal cells to begin forming tissue layers (Called the Gastrula)

21. Human Development:
Development occurs in gestational Trimesters (humans)
First trimester (Wks 1-12)
Differentiation of cells and organogenesis.
Major organs and body plan (brain, spinal cord, heart)
Placenta develops, which connects the mother to the embryo.
By the end of this trimester, fetus is 5cm long

24. Second trimester (Wks 13-24)
- Growth up to 30 cm
- Sex of baby can be determined at end of 1st trimester/beginning of 2nd due to more development of reproductive organs
- Muscles and bones develop more so becomes extremely active inside womb.

26. Third trimester (Wks 25-40)
- Growth up to 50 cm
- last to develop are the LUNGS
- All organs finish developing and mostly baby is just gaining weight
-leads to labor and birth.

28. Fetal Development During Pregnancy Video: https://www. youtube
Fetal Development During Pregnancy Video:  1:25

29. *Multiple zygotes AKA TWINS!!!

30. Reviews *label male reproductive organs practice (Quiz yourself!)
Nervous system
Circ. System
Male Reprod system
Female Reprod system
Fetal Development