Free Kingdom Animalia MCQs with Answers

21. Which one of the following is one of the paths followed by air or oxygen during respiration in the adult male Periplaneta Americana as it enters the animal body?

• A. Spiracle in metathorax, trachea, tracheloes, oxygen diffuses into cells
• B. Mouth, bronchial tube, trachea, oxygen enters cells
• C. Spiracles in prothorax, tracheoles, trachea, oxygen diffuses into cells
• D. Hypopharynx, mouth, pharynx, trachea, tissues

Explanation: The respiratory system is well developed in a cockroach in order to compensate the poorly developed circulatory system. It consists of tracheae, tracheoles and spiracles. The main tracheal trunks open to the exterior on body surface through 10 pairs of segmentally arranged apertures termed spiracles or stigmata. Two pairs of spiracles are thoracic, one between pro and mesothorax and the other between meso and metathorax. Haemocoel contains a network of elastic, closed and branching air tubes or tracheae. The ultimate finer branches of tracheae are called tracheoles which come in contact with the individual body cells. The elaborate tracheal system carries oxygen directly to all the body cells.

22. In which one of the following options are the genus name, its two characters and its phylum not correctly matched?

• A. Pila (i) Body segmented Mollusca (ii) Mouth with radula
• B. Asterias (i) Spiny skinned Echinodermata (ii) Water vascular system
• C. Sycon (i) Pore bearing Porifera (ii) Canal system
• D. Periplaneta (i) Jointed appendages Arthropoda (ii) Chitinous exoskeleton

Explanation: Pila belongs to phylum mollusca. The body of molluscs (soft bodied animals) is unsegmented with a distinct head, muscular foot and visceral hump. Radula is found in the mouth of Pila.

23. Which one of the following pairs of animals are similar to each other pertaining to the feature stated against them?

• A. Pteropus and Viviparity - Ornithorhynchus
• B. Garden lizard and crocodile - Three chambered heart
• C. Ascaris and Metameric Ancylostoma - Segmentation
• D. Sea horse and flying fish - Cold blooded (poikilothermal)

Explanation: Sea horse (Hippocampus) and flying fish (Exocoetus) belong to class osteichthyes of super class pisces. They have two chambered hearts (one auricle and one ventricle) and are cold blooded animals.

24. Which one of the following categories of animals is correctly described with no exception in it?

• A. All reptiles possess scales, have a three chambered heart and are cold blooded
• B. All bony fishes have four pairs of gills and an operculum on each side
• C. All sponges are marine and have collared cells
• D. All mammals are viviparous and possess diaphragm for breathing

Explanation: All bony fishes do have four pairs of gills and an operculum on each side of their bodies. The operculum is a protective bony plate that covers and helps protect the delicate gill filaments. This arrangement allows bony fishes to extract oxygen from the water as it flows over their gills and to expel carbon dioxide. The heart is generally 3 chambered in reptiles but in the crocodile it is 4 chambered. Sponges are generally marine and have collared cells but few fresh water forms can also be seen like Spongilla. All mammals are viviparous (giving birth to young ones) with an oviparous (egg laying) exception: Ornithorhynchus (platypus).

25. What will you look for to identify the sex of the following?

• A. Female Ascaris - sharply curved posterior end
• B. Male frog - a copulatory pad on the first digit of the hind limb
• C. Female cockroach - anal cerci
• D. Male shark - claspers borne on pelvic fins

Explanation: Tail end is straight in female Ascaris, while tail end is curved towards ventral in male Ascaris. Anal cerci is present in both male and female cockroach, while anal style is present only in the male cockroach. The forelimbs in both frogs (male and female) bear small articular pads dorsally at the joints of digit, but the males possess a special nuptial, copulatory pad on ventral side of the first finger of each forelimb. Copulatory pads appear merely as rough patches, but during breeding season, they become thick and sticky. In copulation, the male strongly grips a female under her armpits by means of these pads. Claspers are modified inner edges of pelvic fins in male sharks.

26. In which one of the following the genus name, its two characters and its class/phylum are correctly matched?

• A. Ascaris (i) Body segmented Annelida (ii) Males and females distinct
• B. Salamandra (i) A tympanum represents ear (ii) Fertilization is external Amphibia
• C. Pteropus (i) Skin possesses Mammalia (ii) Oviparous
• D. None of these

Explanation: None of the options is correct. Ascaris is member of phylum Nematoda, which are round worms. They do not have segmented body. In ascaris female is longer than male. Salamandra is member of amphibia. Salamanders do not have tympanum, although they have greatly reduced middle ears and fertilization is usually internal in them. Pteropus is member of class mammalia. They are viviparous. A mantle of golden hair covers the head, neck and shoulders in Pteropus.

27. Which one of the following statements is totally wrong about the occurrence of notochord, while the other three are correct?

• A. It is present only in larval tail in ascidian
• B. It is replaced by a vertebral column in adult frog
• C. It is absent throughout life in humans from the very beginning
• D. It is present throughoutlife in Amphioxus

Explanation: Humans are mammals which are chordates. Phylum chordata includes animals which possess a notochord either throughout or during early embryonic life. In Ascidia (urochordata), notochord is present only in larval tail while in Amphioxus (cephalochordata), it extends from head to tail region and is persistent throughout their life. It is replaced by a vertebral column in adult frog.

28. Ureters act as urinogenital ducts in _

• A. Human males
• B. Human females
• C. Both male and female frogs
• D. Male frogs

Explanation: In male frogs, two ureters act as the urinogenital duct which opens into the cloaca. They run backwards from the kidneys and open into the cloaca. In females, the ureters carry urine alone, while in males both sperm and urine are carried. Hence, they are called urinogenital ducts.

29. Which one of the following statements about all the four of Spongilla, leech, dolphin and penguin is correct?

• A. Penguin is homeothermic while the remaining three are poikilothermic
• B. Leech is a fresh water form while all others are marine
• C. Spongilla has special collared cells called choanocytes which are not found in the remaining three
• D. All are bilaterally symmetrical

Explanation: Spongilla is a common, widely distributed fresh water sponge belonging to phylum porifera. Canal system in Spongilla is essentially of rhagon type with choanocytes restricted to small rounded chambers. It is not found in leeches, dolphins or penguins.

30. Which one of the following kinds of animals are triploblastic?

• A. Flatworms
• B. Sponges
• C. Cnidarians
• D. None

Explanation: Triploblastic is a condition which describes an animal having a body composed of three embryonic germ layers : the ectoderm, mesoderm and endoderm. Most multicellular animals belonging to phylum platyhelminthes to phylum chordata are triploblastic. Ctenophores, sponges and corals are diploblastic.