1. I. Female Reproductive System
A. Ovaries
1. contain oocytes
- humans: about 2 million at birth
a. primary oocytes

2. I. Female Reproductive System
A. Ovaries
1. contain oocytes
- humans: about 2 million at birth
a. primary oocytes
b. arrested in prophase I of meiosis

3. 2. ovulation
a. hormonal fluctuations
b /lifetime (human)
c. ovum
d. is a phase of the estrous cycle

4. B. Oviducts
1. tubes lined with smooth muscle
2. peristalsis
- journey takes 5-7 days in humans
3. fertilization occurs here
- in the first 1/3
- 24 hour window of egg viability (human)

7. C. Uterus
1. endometrium: inner lining where embryo transplants
2. muscular walls (myometrium)
3. cervix
4. horns
- diverse horn structures among mammals

9. II. Embryonic Development (human)
A. Cleavage (is a type of reduction division)
1. first division about 30 hours after fertilization
2. morula = solid ball of cells
- typically the 32-cell stage
- about the same size as egg

10. 3. blastocyst (blastula in some other organisms)
a. hollow ball of cells (contains a blastocoel)
- around cell stage
b. implantation
c. trophoblast (outer layer of cells)
- gives rise to fetal placenta and other membranes

11. B. Extraembryonic membranes
1. form after implantation
2. trophoblast contributes to these membranes
3. amnion
- encloses the fluid-filled amniotic sac containing the embryo
4. chorion
- becomes the fetal portion of the placenta

12. C. Gastrulation
- embryonic cells sorted into distinct layers:
1. endoderm (becomes lining of the gut tube)
2. mesoderm (becomes “internal structures”)
3. ectoderm (becomes nerves and skin)

14. 5 weeks
9 weeks
14 weeks

15. I. Ecology (Chapter 34.1)
A. How organisms react to their environment
B. Varies by location
1. community
- all of the populations of different species living in a particular place
- the biotic components of an ecosystem
2. physical habitat
- the physical place where a community lives
- the abiotic components of an ecosystem
- rocks, water, ground, wind, sun
3. ecosystem =
community + habitat

16. II. Energy Flow (Chapter 37.8-9; 37.14-17)
A. Starts with the sun
1. photosynthesis
2. light energy to chemical energy
3. energy stored in organic molecules (like glucose)

17. B. Producers
1. carry out photosynthesis
- plants, algae, cyanobacteria
2. lowest trophic level
- is the number of consumption levels away from the sun
3. produce “usable” energy sources
- in the process they use CO2 and nitrogen

18. C. Consumers
1. herbivores
- level 2
- are the primary consumers
- most can digest cellulose

19. 2. carnivores
- level 3
- secondary consumers
- sometimes level 4 or 5 (tertiary or quaternary consumers)

20. 3. omnivores
- get starches and some simple sugars from plants
- typically cannot digest cellulose

21. 4. detritovores/decomposers
- get their nutrients/energy from detritus
- mainly bacteria and fungi
- but includes many animals (scavengers)

22. Complex food webs

23. D. Limitations of food chains (food webs)
1. much energy used lost as heat (often 50%)
- also can’t get energy from everything ingested
(lost as waste)

24. 2. herbivore utilizes only 10% of energy stored in plant molecules
3. carnivore utilizes only 10% of energy stored in herbivore
4. rarely over 4 or 5 trophic levels in an ecosystem

25. What is the best way to utilize 10 pounds of grain?