organism reproductive strategies: Frogs & hydra

Hydra leopard frogs Freshwater animals (belongs in the phylum Cnidaria) Lifespan: Can live forever (depending on their living condition) Adults: 1 inch in length Breed every two days on average Amphibians (cold-blooded vertebrate with gills) Lifespan: 2-4 years Adults: 2-4 inches in length Breed once a year Males are smaller than females Uses special call to attract mate

Reproductive category & description Frogs use sexual reproduction to reproduce. Some characteristics of their reproduction strategy include: Number of offspring produced per cycle: 300-6500 eggs Frequency of cycle: 1 year Age of sexual maturity: 3 yrs. old Length of gestation: None Males use a call to attract females Males clasp females from behind causing her to lay hundreds of eggs As eggs are laid in water the male frog expels sperm over the eggs to fertilize them Takes place at either night or dawn in spring Eggs sometimes attach to water plants

Reproductive category & description cont. Hydra use both sexual and asexual reproduction to reproduce. Some characteristics of their reproduction strategies include: Number of offspring produced per cycle: 1 Frequency of cycle: Every two days Age of sexual maturity: 5-10 days Length of gestation: N/A Reproductive strategies: Asexual: Forms bud on the body wall that eventually evolve into one hydra that breaks off from parent. Sexual: Hydra produce both ovaries and testes. Eggs in the ovary are fertilized by sperm shed into the water. The zygote then develops into an embryo and forms a hard shell to survive through the winter. It then hatches in the spring.

Advantages & disadvantages Frog advantages: More eggs are laid at once --- -> increased chance of having offspring that survive Disadvantages: Eggs are only laid once a year 95% of offspring don’t make it Hydra advantages: Reproduces frequently Can reproduce in harsh weather through sexual reproduction Disadvantages: Asexual reproduction sometimes depends on how well fed the hydra is

Hydra & frog comparison Similarities: Both use sexual reproduction and release eggs/zygote into water Both have no gestation length Differences: Hydras can reproduce asexually through a process called budding Frogs produce many offspring at one time Hydras only produce one offspring at a time Hydra’s cycle is more frequent than a frog’s