External vs. internal fertilization: examples and advantages

📚 Quick Study Guide

• 🥚 External Fertilization: Occurs outside the female's body. Think fish and amphibians releasing eggs and sperm into the water.
• 🌱 Internal Fertilization: Occurs inside the female's body. Common in mammals, birds, and reptiles where sperm fertilizes the egg internally.
• 🌊 External Fertilization Advantages: Produces a large number of offspring, increasing the chances of survival for some.
• 🛡️ External Fertilization Disadvantages: Higher risk of predation and environmental hazards for eggs and offspring.
• 🤰 Internal Fertilization Advantages: Increased protection of the egg and developing embryo, higher success rate of fertilization.
• 💔 Internal Fertilization Disadvantages: Fewer offspring are produced compared to external fertilization.
• 🔬 Key Difference: Location of fertilization; outside (external) vs. inside (internal) the female's body.

🧪 Practice Quiz

1. Which of the following is an example of an animal that uses external fertilization?
   1. A. Lion
   2. B. Frog
   3. C. Snake
   4. D. Chicken
2. What is a major advantage of internal fertilization?
   1. A. Production of a large number of offspring
   2. B. Increased protection of the developing embryo
   3. C. Fertilization occurs in water
   4. D. No parental care required
3. In which environment is external fertilization most common?
   1. A. Desert
   2. B. Forest
   3. C. Aquatic
   4. D. Arctic
4. Which of these animals uses internal fertilization?
   1. A. Salmon
   2. B. Sea Urchin
   3. C. Dolphin
   4. D. Starfish
5. What is a disadvantage of external fertilization?
   1. A. Requires a mate
   2. B. High risk of predation for eggs
   3. C. Requires internal development
   4. D. Guarantees offspring survival
6. Which process is exclusive to internal fertilization?
   1. A. Release of gametes
   2. B. Development in an egg
   3. C. Copulation
   4. D. Meiosis
7. Which of the following best describes internal fertilization?
   1. A. Fertilization occurs outside the body
   2. B. Fertilization occurs inside the body
   3. C. Fertilization is dependent on water
   4. D. Fertilization involves no gametes