There has been an increase in the number of chambers in heart during evolution of vertebrates. Give the name of the class of vertebrates having two, three or four chambered heart.

Which one of the following sets of animals share a four chambered heart?

Give scientific reason: Vertebrates have been slowly originated from invertebrates.

Give scientific reason. Left ventricle is thick than all other chambers of heart.

A mixture of fuel and oxygen is burned in a constant- volume chamber surrounded by a water bath. It was noticed that the temperature of water is increased during the process.Treating the mixture of fuel and oxygen as the system. Has heat been transferred?

A mixture of fuel and oxygen is burned in a constant- volume chamber surrounded by a water bath. It was noticed that the temperature of water is increased during the process. Treating the mixture of fuel and oxygen as the system. Has work been done?

A part of periodic table is shown in the adjacent figure. a. Write the symbol of the element 'B'. b. Will elements 'C' and 'D' have same number of valence electrons? c. Arrange elements 'A', 'B' and 'C' in increasing order of their metallic character. d. What is the number of electrons in L shell of element 'E'? e. Name any two elements that will have properties similar to that of element 'A'

Read the paragraph and answer the questions given below : Locomotion is considered as an important characteristics of the animals. However, animals belonging to Porifera are said to be sedentary. Every other phylum has typical locomotory organs. E.g. Nereis crawls with the help of parapodia, whereas earthworm buries in soil by setae. Spiders have four pairs of walking legs, crab has five while all insects have three pairs of walking legs. The walking legs are also called appendages. Starfish moves with the help of tube feet. Snails and bivalves use muscular foot for locomotion. Birds flying with their spread out wings and fish swimming with their fins, both have spindle-shaped body tapering at both the ends. While flying or swimming such body offers least resistance during locomotion. Mammals have two pairs of limbs while animals like snakes are limbless. Other animals belonging to the class of snakes also have very weak limbs.which make them creep on the ground. Answer the question: Which class of animals show weak legs?

Read the paragraph and answer the questions given below : Locomotion is considered as an important characteristics of the animals. However, animals belonging to Porifera are said to be sedentary. Every other phylum has typical locomotory organs. E.g. Nereis crawls with the help of parapodia, whereas earthworm buries in soil by setae. Spiders have four pairs of walking legs, crab has five while all insects have three pairs of walking legs. The walking legs are also called appendages. Starfish moves with the help of tube feet. Snails and bivalves use muscular foot for locomotion. Birds flying with their spread out wings and fish swimming with their fins, both have spindle-shaped body tapering at both the ends. While flying or swimming such body offers least resistance during locomotion. Mammals have two pairs of limbs while animals like snakes are limbless. Other animals belonging to the class of snakes also have very weak limbs.which make them creep on the ground. Answer the question: In which class of animals the forelimbs are modified?

Read the paragraph and answer the questions given below : Locomotion is considered as an important characteristics of the animals. However, animals belonging to Porifera are said to be sedentary. Every other phylum has typical locomotory organs. E.g. Nereis crawls with the help of parapodia, whereas earthworm buries in soil by setae. Spiders have four pairs of walking legs, crab has five while all insects have three pairs of walking legs. The walking legs are also called appendages. Starfish moves with the help of tube feet. Snails and bivalves use muscular foot for locomotion. Birds flying with their spread out wings and fish swimming with their fins, both have spindle-shaped body tapering at both the ends. While flying or swimming such body offers least resistance during locomotion. Mammals have two pairs of limbs while animals like snakes are limbless. Other animals belonging to the class of snakes also have very weak limbs.which make them creep on the ground. Answer the question: Which phylum has a characteristic of jointed appendages?

Read the paragraph and answer the questions given below : Locomotion is considered as an important characteristics of the animals. However, animals belonging to Porifera are said to be sedentary. Every other phylum has typical locomotory organs. E.g. Nereis crawls with the help of parapodia, whereas earthworm buries in soil by setae. Spiders have four pairs of walking legs, crab has five while all insects have three pairs of walking legs. The walking legs are also called appendages. Starfish moves with the help of tube feet. Snails and bivalves use muscular foot for locomotion. Birds flying with their spread out wings and fish swimming with their fins, both have spindle-shaped body tapering at both the ends. While flying or swimming such body offers least resistance during locomotion. Mammals have two pairs of limbs while animals like snakes are limbless. Other animals belonging to the class of snakes also have very weak limbs.which make them creep on the ground. Answer the question: What are the locomotory organs in phylum Annelida?