Biology Multiple Choice Questions on “Animals Structural Organisations – Frogs-1”.
1. Which of these statements is true about frog?
a) It lives both on land and in sea water
b) They cannot survive in freshwater
c) Rana tigrina is a rare species
d) They belong to class Amphibia
Answer: d
Clarification: Frog belongs to class Amphibia. It lives on land and in fresh water. The species Rana tigrina is the most common in India. Frogs are chordates and are poikilotherms. This means they do not have a constant body temperature.
2. Frogs are _______
a) homeothermic
b) warm-blooded
c) poikilothermic
d) heterothermic
Answer: c
Clarification: Frogs are poikilothermic animals. This means that they have a fluctuating body temperature which varies with the environmental conditions, or they lack constant body temperature.
3. Which of these methods are utilized by frogs for protection?
a) Speed
b) Spikes
c) Mimicry
d) Playing dead
Answer: c
Clarification: Frogs have the ability to change their color to defend themselves from predators. This phenomenon is known as camouflage and the protective coloration using which it hides in its surroundings is knows as mimicry.
4. Which of these statements is false about frogs?
a) They do not aestivate
b) They change color
c) They live in burrows
d) They hibernate
Answer: a
Clarification: Frogs have the ability to change color to protect themselves from predators. This camouflaging technique is called mimicry. They live in burrows to shelter themselves from extreme weather and they show both aestivation and hibernation.
5. Which of these describes the skin of frog?
a) Thick, leathery
b) Smooth, slippery
c) Hard, dry
d) Thin, membranous
Answer: b
Clarification: The skin of a frog is smooth and slippery due to the presence of mucus. The skin has a moist characteristic which is maintained. A frog does not drink water but has the ability to absorb water through its skin.
6. Which of these are the divisions of the body of a frog?
a) Head, trunk, abdomen
b) Head, thorax, abdomen
c) Head, trunk
d) Head, thorax, trunk
Answer: c
Clarification: The body of the frog is divided into a head and a trunk. Neck and tail are absent. Frogs are green with dark irregular spots on the dorsal side. On the ventral side, they are pale yellow in color.
7. Which of these structures protects the eyes of the frog in water?
a) Nictitating membrane
b) Tympanum
c) Bidder’s canal
d) Cloaca
Answer: a
Clarification: The nictitating membrane protects the eyes of the frog in water. The tympanum is the ear of the frog. Cloaca are excretory organs. Bidder’s canal is a part of the male reproductive system of frogs.
8. Which of these structures in frog receive sound signals?
a) Webbed feet
b) Skin
c) Nictitating membrane
d) Tympanum
Answer: d
Clarification: The tympanum is the ear of frog. It receives sound signals from the environment. The tympanum is a membranous structure. The received environmental sound signals is then transmitted to the nervous system.
9. How many digits does the forelimb and hindlimb of frog have respectively?
a) 3, 4
b) 5, 4
c) 4, 5
d) 4, 3
Answer: c
Clarification: Each forelimb of frog has four digits while each hindlimb of frog has five digits. The hindlimbs are larger and more muscular than the forelimbs. The limbs are used for leaping, swimming and burrowing.
10. Frogs show sexual dimorphism. True or false?
a) True
b) False
Answer: a
Clarification: Frogs show sexual dimorphism. This means that apart from differences in reproductive organs of the two sexes, the appearance or phenotypic characteristics differs with sex within the same animal species.
11. Which of this is not a distinguishing feature of a male frog?
a) Narrow abdomen
b) Copulatory pad
c) Vocal sacs
d) Moist, slippery skin
Answer: d
Clarification: All frogs have characteristic moist, slippery skin. This is due to the secretion of mucus on the surface of the skin. Male frogs can be differentiated from female frogs by distinguishing features such as narrow abdomen, copulatory pad and vocal sacs.
12. Where are the copulatory pads in male frog present?
a) Second digit of the hindlimbs
b) First digit of the hindlimbs
c) First digit of the forelimbs
d) Second digit of the forelimbs
Answer: c
Clarification: The copulatory pads of the male frog are present on the first digit of the forelimbs. Frogs show sexual dimorphism and the presence of copulatory pads in male frogs is a distinguishing feature of the two sexes.
13. Frogs are ______
a) herbivores
b) omnivores
c) carnivores
d) scavengers
Answer: c
Clarification: Frogs are carnivores. This means that their diets consist of food material which are solely animal in origin. Frogs normally feed on insects such ad flies, mosquitoes, dragonflies and worms.
14. Which of these characteristics of frog is the reason for its short alimentary canal?
a) Carnivorous
b) Sexual dimorphism
c) Amphibian
d) Chordate
Answer: a
Clarification: Frogs are carnivorous. This means that their diet consists of food which is purely of animal origin. For this reason, the length of its intestine is reduced. Thus, frogs have a short alimentary canal.
15. Identify ‘3’ in the pathway of food ingested by frog.
a) Larynx
b) Pharynx
c) Gizzard
d) Crop
Answer: b
Clarification: Structure 3 is pharynx. In the digestive system of frog, the pharynx lies after the buccal cavity and before the esophagus. The structures larynx, gizzard and crop are not a part of the digestive system of frog.