LMS

They are directly evolved from animal like protists. They do not have any organs system and are poorly developed than other organisms in kingdom animalia.  

Mesenchyme of sponges is a non-cellular gelatinous mass while mesenchyme of acoelomates is cellular structure

Coelom (body cavity) is formed due to splitting of mesoderm at embryonic stage. Its outer layer is called parietal layer which underline the body wall, while inner layer is called visceral layer that surround the endoderm. 

Pseudocoelomdevelops from the blastocoel of the embryo and it is bounded externally by the muscles and internally by the cuticle of the intestine

Some sponge species reproduce sexually. These are mostly hermaphrodite, mostly protandrous, i.e. male sex cells develop first. In some sponges the sexes are separated.

Itis commonly known as hook worm. It is a parasite of human small intestine. It holds the villi of intestine and sucks blood and body fluid. During feeding they produce an anticoagulant to prevent clotting of blood and after feeding leave the wound bleeding. In children it can cause severe anemia and retard physical and mental growth.

It is commonly known as pin worm is cosmopolitan but more common in Europe and America. They are parasites in the human caecum, colon and appendix. Their movement causes intense itching of anus, inlammation of mucous membrane of colon and appendix resulting in insomnia and loss of appetite

They have metanephridium for excretion.

Burrowing activity of earthworms(Pheretimapraepinguis) permits greater penetration of air into the soil, and improves drainage capacity of the soil.Earthworm is perhaps most active segmented worm in churning the soil

Enterobiusvermicularis commonly known as pin worm. Pinworms are parasites in the human caecum, colon and appendix. Their movement causes intense itching of anus, inflammation of mucous membrane of colon and appendix resulting in insomnia and loss of appetite

Their exoskeleton enable them to face rough environmental conditions, protects from anomies and also against to the dehydration.  

Echinoderms have high regenerative ability while chordates have limited regenerative ability.  Both phylums have mesoderm which is derived from the cells close to the blastopore. Both possess mesodermal endo-skeleton.

Varanope was reptile that was found as fossil in Texas. Probably at least five groups of such mammal-like reptiles developed mammalian characters and were 50% mammals. Mammals became dominant in the Cenozoic period.

Voice producing organ in birds is called syrinx, it is situated at the lower end of trachea near the origin of the two bronchi.

All animals belong to kingdom Animalia are multicellular, diploid, have embryonic development and eukaryotic but they are not unicellular.

These animals are composed of many cells however there is no tissue organization and have no organs. Sponges lack symmetry. In most sponges the body wall is formed of an outer layer, pinacoderm, made up of cells called pinacocytes: and an inner layer choanoderm made of lagellated collar cells called choanocytes.

Locust swarms devastate crops and cause major agricultural damage which results in famine and starvation. Honey bee gives honey. Silk worms give silk and butterfly is beneficial for pollination.

They have diffused nervous system that appeared in kingdom Animalia first time. 

Arthropods have open circulatory system and chitinous exoskeleton that protects them from enemies, rough environment and dehydration. Any other phylum of invertebrate does not has these characters. 

Parasitology is the branch of biology that deals with the study of parasite that get shelter and food from other animals.

Animals from phylum coelenterates and adult animal from phylum Echinodermata have radial symmetry.

Sycon is asymmetric because it is a sponge. Taenia is flat worm and triploblastic. Locusts are insect and triploblastic. Gorgonia is diploblastic with radial symmetry.

The notochord develops ventral to ectoderm and this means it originates from mesoderm. First, it lies below the ectoderm then below the neural plate, and finally under the neural tube

As gastrula stage has germinal layers during embryo development. So organism would be identified either it is triploblastic or diploblastic. 

Arthropods are proterostomes in which cleavage isdeterminate (fate of blastomeres is foretold). Each blastomere developed into its special structure.

Pinworm belong to phylum nematode which mean it is proterostomes. 

Frog does respiration by all means which are called Cutaneous respirationBuccal respirationPulmonary respiration

Reptiles move by using their limbs and tails. They cannot up lift their body.

The ancestors of mammals lived simultaneously along with reptiles during the Jurassic times and have been called mammal-like reptiles. Some were only of the size of mice and lived on trees. One of these early reptile was varanope that was found as fossil in Texas. Probably at least five groups of such mammal-like reptiles developed mammalian characters and were 50% mammals. Mammals became dominant in the Cenozoic period

These all characters of animals belonging to class mammals. Different species from this class has different gestation period to birth their offspring. 

Bats are flying mammals. Their limbs are completely webbed which are used for flying

Frog is cooled blooded animal. Because it is an amphibian.