Ch 46a reproduction - Both asexual and sexual reproduction...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Asexual reproduction involves the formation of individuals whose genes all come from one parent. There is no fusion of sperm and egg. Sexual reproduction is the formation of offspring by the fusion of haploid gametes. Ovum : female gamete - usually large and nonmotile. Spermatozooan : male gamete - usually small and motile. Sexual reproduction increases genetic variation among offspring. Both asexual and sexual reproduction occur in the animal kingdom
Background image of page 2
Sexual Reproduction Asexual Reproduction
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sexuality Hermaphroditism versus Gonochorism Acropora sp., a hermaphoditic coral Fungia scutaria , a gonochoric coral eggs sperm packet egg cloud Hermaphroditism: both sexes in the same individuals Gonochorism: sexes are separate
Background image of page 4
Brooding vs Broadcast Spawning Brooding vs Broadcast Spawning broadcast spawner Pocillopora damicornis , a brooder planula in polyp released gametes D. Gulko Brooding: eggs develop to planula stage in gastrovascular cavity of parent polyp Broadcast Spawning: eggs and sperm are shed into the water column where fertilization and development occurs
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sequential hermaphroditism : an individual reverses its sex during its lifetime. Protogynous : female to male Protandrous : male to female
Background image of page 6
Parthenogenesis Egg development without fertilization Aphid Daphnia Honeybee Whiptail lizard Komodo Dragon Hammerhead Shark
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Internal fertilization requires cooperative behavior that leads to copulation. Internal and external fertilization both depend on mechanisms ensuring that mature sperm encounter fertile eggs of the same species
Background image of page 8
External fertilization requires a moist habitat that will protect a developing egg from desiccation and heat stress. Specific mating behaviors assure that sperm and egg will be in the same place at the same time. Surinam Toad
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Pheromones : chemical signals released by one organism that influence the behavior of other individuals of the same species. Many act as male attractants. female male
Background image of page 10
Internal fertilization usually results in the production of fewer zygotes than does internal fertilization. However, the survival rate is lower for external fertilization than it is for internal fertilization. Species with internal fertilization usually produce fewer zygotes but provide more parental protection than species with external fertilization
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The externally fertilized eggs of fishes and amphibians are surrounded by a gelatinous coat. The internally fertilized amniote eggs of birds, reptiles, and monotremes are protected by calcium and protein shells. In mammals the embryo is retained within the females reproductive tract. Platypus egg
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/20/2011 for the course BIOL 172 taught by Professor Huddleston,m during the Spring '08 term at University of Hawaii, Manoa.

Page1 / 65

Ch 46a reproduction - Both asexual and sexual reproduction...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online