Module 3, lecture 5: Reproductive Physiology Flashcards
(19 cards)
Asexual reproduction
When an organism produces offspring genetically identical to itself without a mate
Binary fission - asexual reproduction
When an organism divides into two identical cells
Budding - asexual reproduction
A new organism grows off the body of the parent
Fragmentation - asexual reproduction
where an organism breaks into pieces, and each piece can grow into a new individual
Parthenogenesis - asexual reproduction
When an egg develops into an individual without being fertilized
Sexual reproduction
When two parents contribute genetic material to produce genetically unique offspring
Viviparous
When embryos develop inside the parents body
Ovoviviparous
Animals produce eggs that hatch inside the parent’s body
Oviparous
animals lay eggs, and the embryos develop and hatch outside the parent’s body
sneaker male
a male that can’t reproduce without pretending to be female
Example of Ovoviviparity
Sand tiger shark eggs hatch and embryonic sharks swim inside the uterus. Only 1 or 2 survive because they eat each other
Bluehead Wrasse
- Live in groups with mostly females, 1–2 dominant males, and sneaker males
- If dominant male dies, the largest female or sneaker male becomes the new male
Hermaphroditism
An individual has both male and female reproductive organs and can perform both reproductive roles
Why would natural selection favour sex change?
switching sex can increase fitness if being male or female gives a greater advantage at a certain size or condition
Wolverine Traits
- Circumpolar distribution
- Large home ranges
- Generally solitary
- Low density populations
- Don’t respond well to urbanization and habitat change
How does wolverine ecology make reproduction challenging?
- live in low-density, harsh northern areas, making it hard to find mates and enough food
reproductive diapause
- delay in embryo development
- allowing birth to occur when environmental conditions are more favorable
What are main parts of human reproduction?
- Humans have continuous gamete production and ovulation
- high maternal investment in pregnancy and childcare
- many blastocysts do not develop to full term
Why might natural selection favour shifting pregnancy maintenance to the embryo?
- It allows the embryo to produce hormones to maintain pregnancy, helping the mother invest only in viable offspring
- Favours quality over quantity
