External fertilization is characterized by the release of both sperm and eggs into an external environment; sperm will fertilize the egg outside of the organism, as seen in spawning.
Internal fertilization is characterized by sperm fertilizing the egg within the female; the three methods include: oviparity (egg laid outside female body), ovoviparity (egg held within female), and viviparity (development within female followed by live birth).
Internal fertilization protects the fertilized egg or embryo from predation and harsh environments, which results in higher survival rates than can occur with external fertilization.
Ovoviparity is characterized by an organism retaining a fertilized egg inside the body where development occurs and nourishment is received from the yolk.
Viparity is characterized by an organism which has its young develop within the female and nourishment is received directly from the mother via a placenta.
Key Terms
oviparous: egg-laying; depositing eggs that develop and hatch outside the body as a reproductive strategy
viviparous: being born alive, as are most mammals, some reptiles, and a few fish (as opposed to being laid as an egg)
ovoviparity: eggs are retained in the female, but the embryo obtains its nourishment from the egg’s yolk
External and Internal Fertilization
External Fertilization
External fertilization usually occurs in aquatic environments where both eggs and sperm are released into the water. After the sperm reaches the egg, fertilization can then take place. Most external fertilization happens during the process of spawning where one or several females release their eggs and the male(s) release sperm in the same area, at the same time. The release of the reproductive material may be triggered by water temperature or the length of daylight. Nearly all fish spawn, as do crustaceans (such as crabs and shrimp), mollusks (such as oysters), squid, and echinoderms (such as sea urchins and sea cucumbers). Pairs of fish that are not broadcast spawners may exhibit courtship behavior. This allows the female to select a particular male. The trigger for egg and sperm release (spawning) causes the egg and sperm to be placed in a small area, enhancing the possibility of fertilization.
image
Figure 43.2A.1 : Anemone fish protecting its spawn: An image of an Anemone fish protecting its spawn. The anemone fish utilizes a form of external fertilization.
Answers & Comments
Explanation:
External fertilization is characterized by the release of both sperm and eggs into an external environment; sperm will fertilize the egg outside of the organism, as seen in spawning.
Internal fertilization is characterized by sperm fertilizing the egg within the female; the three methods include: oviparity (egg laid outside female body), ovoviparity (egg held within female), and viviparity (development within female followed by live birth).
Internal fertilization protects the fertilized egg or embryo from predation and harsh environments, which results in higher survival rates than can occur with external fertilization.
Ovoviparity is characterized by an organism retaining a fertilized egg inside the body where development occurs and nourishment is received from the yolk.
Viparity is characterized by an organism which has its young develop within the female and nourishment is received directly from the mother via a placenta.
Key Terms
oviparous: egg-laying; depositing eggs that develop and hatch outside the body as a reproductive strategy
viviparous: being born alive, as are most mammals, some reptiles, and a few fish (as opposed to being laid as an egg)
ovoviparity: eggs are retained in the female, but the embryo obtains its nourishment from the egg’s yolk
External and Internal Fertilization
External Fertilization
External fertilization usually occurs in aquatic environments where both eggs and sperm are released into the water. After the sperm reaches the egg, fertilization can then take place. Most external fertilization happens during the process of spawning where one or several females release their eggs and the male(s) release sperm in the same area, at the same time. The release of the reproductive material may be triggered by water temperature or the length of daylight. Nearly all fish spawn, as do crustaceans (such as crabs and shrimp), mollusks (such as oysters), squid, and echinoderms (such as sea urchins and sea cucumbers). Pairs of fish that are not broadcast spawners may exhibit courtship behavior. This allows the female to select a particular male. The trigger for egg and sperm release (spawning) causes the egg and sperm to be placed in a small area, enhancing the possibility of fertilization.
image
Figure 43.2A.1 : Anemone fish protecting its spawn: An image of an Anemone fish protecting its spawn. The anemone fish utilizes a form of external fertilization.
Answer:
Turtle
Tuatara
Lizard
Snake
Chicken
Falcon
Owl
Parrot