36 public questions tagged with this topic.
Most reptiles have a three-chambered heart, except crocodiles, which have a four-chambered heart. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function.
ZW chromosome system defines female heterogamety found predominantly in birds, some reptiles, fish and Lepidoptera butterflies where females are ZW and males ZZ. In birds two copies of DMRT1 on Z promote testis formation while single copy plus W-linked factors HINTW and FET1 promote ovary. This system evolved independently from mammalian XY multiple times, demonstrating convergent evolution of sex chromosomes where heterogametic sex differs. Identification of ZW in birds contrasts with mammalian XX/XY and Drosophila XY but X:A counting, illustrating evolutionary diversity of mechanisms achieving sexual dimorphism.
Ref: Gilbert, Developmental Biology, 12th ed., Chapter 6: ZW system in birds.
Thick-shelled eggs prevented desiccation, enabling reptiles to dominate terrestrial environments.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
The Cretaceous-Paleogene extinction marked the end of large reptiles (dinosaurs) and the rise of mammals.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Reptiles and birds excrete uric acid as a semisolid paste to conserve water.
Ref: NCERT Class 11 Biology Chapter 16: Excretory Products and their Elimination Modes of Excretion - Ammonotelism Ureotelism Uricotelism
Reptiles and birds are uricotelic, meaning they excrete uric acid to conserve water.
Ref: NCERT Class 11 Biology Chapter 16: Excretory Products and their Elimination Modes of Excretion - Ammonotelism Ureotelism Uricotelism
Both reptiles and birds possess scales, which indicates their evolutionary connection.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Aves and Mammalia
Both reptiles and birds possess scales, which indicate their evolutionary relationship.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Aves and Mammalia
Reptiles have dry, cornified skin covered with epidermal scales or scutes.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Aves and Mammalia
Both amphibians and reptiles are poikilothermic (cold-blooded), meaning their body temperature varies with the environment (NCERT, Chapter 4, page 58). Warm-bloodedness is specific to birds and mammals, mammary glands to mammals, and feathers to birds.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Aves and Mammalia
Both amphibians and most reptiles have a three-chambered heart, except for crocodiles, which have a four-chambered heart.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Amphibia and Reptilia
Both amphibians and most reptiles have a three-chambered heart, except crocodiles, which have a four-chambered heart.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Vertebrata - Amphibia and Reptilia
