Question

Which one is present in the integument of the frog but not in mammals?
A) Sweat glands
B) Dermis
C) Stratum germinativum
D) Mucous Glands

Answer 1

Hint: Integument is the continuous outer covering (like skin, shell) on an organism that protects the body or organ of an organism from the outer environment.

Complete answer:
Both mammals and frogs are vertebrates. The frog does not have any scales, feathers, or hairs covering its surface like any other vertebrates. The vertebrates have two layers: an outer layer i.e. epidermis and an inner layer i.e. dermis. The outermost layer consists of a single layer stratum corneum (flattened cells). The dermis consists of two layers i.e. stratum spongiosum and stratum compactum.

Option A: The sweat glands are part of the integumentary system in many vertebrates. They are generally found on the epidermal layer. They are found in mammals but not in frogs as the skin of the frog is already moist so this is an incorrect option.

Option B: The integumentary system in all vertebrates including mammals contains two layers i.e. epidermis and dermis. Therefore this is an incorrect option.

Option C: The mammals have 5 layered epidermises and the status germinativum is the deepest layer of the epidermis. This layer is having special melanin contacting cells called melanocytes. This is absent in frogs therefore this is an incorrect option.

Option D: The frogs respire through their skin i.e. cutaneous respiration. The mucous glands on the skin of the frogs or amphibians prevent the skin from getting dry on the land due to respiration. It also provides mechanical and bacterial protection by keeping the skin moist. The mammals do not have mucous glands on the skin but they are present in the inner tract like the respiratory tract. Therefore this is the correct option.

Hence the correct answer is option ‘D’.

Note: The mammals do not have cutaneous respiration but they have special organs like lungs for their respiration. The mammals have mucous glands in this respiratory tract to prevent it from drying not on their skin.