Problem 206 - Objective Biology for NEET

Question

Sexes is separate, internal fertilization, oviparous and direct development is seen in case of (a) Chelone (b) Testudo (c) Bangarus (d) All of these

Step-by-Step Solution

Answer

The animals matching the given characteristics are Chelone and Testudo. The correct answer should be a combination of these two options but since it's not available, there's no correct choice among the given ones.

Step 1: Evaluate Characteristics

The first step in this task is to evaluate the characteristics of each of the given options. Each one is a different type of reptile.

Step 2: Chelone

Chelone represents sea turtles. In case of sea turtles, sexes are separate, fertilization is internal, they are oviparous and exhibit direct development.

Step 3: Testudo

Testudo refers to tortoises. Like sea turtles, tortoises too have separate sexes, undergo internal fertilization, are oviparous and show direct development.

Step 4: Bangarus

Bangarus refers to snakes, specifically cobras. Though they meet the criteria of having separate sexes, internal fertilization, and direct development, not all snake species are oviparous. While some lay eggs (oviparous), others give live birth (viviparous). Thus, snakes partially meet the criteria. we cannot conclusively categorize all snakes as having the required characteristics.

Step 5: Comparison and Conclusion

After analysis, we can conclude that the characteristics of Chelone and Testudo match the statement, hence, indicate that 'all of these' is not a correct option.

Key Concepts

Internal Fertilization

Internal fertilization is an important reproductive strategy in many animals, including reptiles. It occurs when sperm is deposited inside the female’s body, which provides a protected environment for fertilization. This process is often accompanied by specific mating behaviors and physical adaptations in reptiles.

• Internal fertilization ensures a higher chance of successful reproduction since the eggs are fertilized within the controlled environment of the female’s body.
• The male typically uses a specialized organ to transfer sperm.

This reproductive strategy is prevalent among reptiles like sea turtles and tortoises, as well as in other animals such as birds and mammals. It allows these creatures to reproduce effectively in diverse environments, ensuring the continuation of their species.

Oviparous

In the animal kingdom, 'oviparous' refers to species that lay eggs outside the female's body. Many reptiles, including sea turtles and tortoises, are oviparous. They produce eggs that contain all the necessary nutrients for the developing embryo, allowing it to mature until it hatches.

• Being oviparous gives the advantage of producing multiple offspring at once.
• This characteristic is common in birds and reptiles.

The young ones are often left to hatch and survive on their own, which reduces the energy and resources the parents need to invest in caring for their young after laying the eggs. These strategies cater to survival across various environments.

Direct Development

Direct development refers to a type of growth in which the embryo develops into a miniaturized adult form inside the egg and hatches without a larval stage. Reptiles like sea turtles and tortoises exhibit direct development, significantly impacting their life cycles.

• This means after hatching, the young generally resemble the adults closely.
• There's no need for metamorphosis like in amphibians or insects.

Direct development can be advantageous as it allows immediate adaptation and growth in the habitat, avoiding vulnerable developmental stages. It is a prevalent trait in environments where a stable and protected childhood is necessary for survival.

Sea Turtles

Sea turtles are fascinating reptiles known for their remarkable reproduction strategies. They exhibit several distinct traits:

• They practice internal fertilization and are oviparous, laying eggs on sandy beaches.
• Following internal fertilization, females travel long distances to find suitable nesting sites.

Sea turtles also demonstrate direct development; their hatchlings begin life ready to face the ocean. This species' reproductive habits include returning to the same beaches where they were born to lay their eggs. Conservation efforts are crucial for sea turtles due to habitat destruction and climate change impacts.

Tortoises

Tortoises are another type of reptile closely related to sea turtles. They share many reproductive characteristics:

• Tortoises are oviparous, laying eggs on land, often in burrowed nests they carefully choose or create.
• They practice internal fertilization, ensuring the protection of the developing embryo inside the mother until it is laid.

Tortoises also follow direct development, meaning that hatchlings are equipped to survive in harsh terrestrial environments. Unlike sea turtles, tortoises primarily dwell on land and are well adapted to a range of terrestrial ecosystems. Understanding their reproductive behavior helps in efforts to protect these fascinating creatures from various environmental threats.