Reproductive Strategies, Biogeochemical Cycles, and Species Interactions

Internal Fertilization Strategies

• Oviparity:
  • Internal fertilization occurs.
  • Egg is deposited outside the body.
  • Examples: Birds, chickens
• Ovoviviparity:
  • Internal fertilization occurs.
  • Embryo stays within the mother.
  • Embryo receives nutrients directly from the egg.
  • Examples: Bony fish, cartilaginous fish
• Viviparity:
  • Internal fertilization occurs.
  • Embryo matures inside the parent.
  • Embryo receives nutrients from the mother.
  • Examples: Mammals, humans

Male Reproductive System Parts

• Testes:
  • Paired structure that produces sperm (spermatogenesis).
  • Located in the scrotal sac to keep testes cooler.
• Epididymis:
  • Site of sperm maturation.
• Vas Deferens:
  • Tube that transports sperm to the next part of the system.
• Urethra:
  • Part of both the urinary and reproductive systems.
• Penis:
  • Composed of 3 columns of spongy erectile tissue.
  • Blood pools in the area during erection.
  • Smaller arteries dilate to allow blood in, and arteries that let blood out close.
• Seminal Fluid:
  • Sperm:
  • Secretion from the seminal vesicle: Nutrients for sperm.
  • Secretion from the prostate gland: Activates sperm.
  • Secretion from the bulbourethral gland: Lubricant for sperm.

Female Reproductive System Parts

• Ovaries (gonads):
  • Site for oogenesis (egg production).
• Ducts:
  • Oviducts (uterine/fallopian tubes): Attach from ovary to uterus; fimbriae sweep eggs from ovaries.
  • Uterus: Narrow end called cervix; embryo embeds in the lining (endometrium).
  • Vagina: Mucosal lining has infolds to allow for expansion.
• External Genitalia:
  • Clitoris: Homologous to the penis; shaft of erectile tissue.
  • Hymen: Thin membrane obstructing vaginal opening; tearing doesn't necessarily indicate virginity, as it can be torn by normal activities, but may stay intact even through intercourse.

Unspecified Topics

• Events of the menstrual cycle
• Comparison of bacterial vs. viral STDs with examples
• Difference between approximate and ultimate causation with examples

Biogeochemical Cycles

• Hydrological (water) cycle:
  • Precipitation (water falling from sky)
  • Infiltration (water enters the ground) / runoff (excess water runs off the surface into bodies of water)
  • Evaporation (heat pulls water to evaporate) / evapotranspiration (water gets pulled out of plants)
  • Condensation (clouds formed)

Native, Exotic, and Invasive Species

• Native plants: Plants that have coevolved with local organisms
• Exotic and invasive: What they are and their importance in the environment

Species Interactions

• Neutralism: Two individuals are neutral to each other, don't hurt or help (flower far away from a tree)
• Amensalism: One is neutral to the other, the other is harmed by the other (mesquite trees release waste into soil, kills off other trees)
• Commensalism: One benefits, one is neutral (bird following a cow/ tractor which moves the grass and insects for the birds)
• Competition: Both harm each other
• Mutualism: Both benefit each other (bees and flowers)
• Predation/Parasitism: One benefits, one is harmed (predator eats prey: lion eats gazelle; one has host: leech on human)