Invertebrate Zoology

The larvae of the silk moth are known as silkworms.

During the larval stage, the worms shed their skin four times.

This is the correct answer. 

This is the correct option. Houseflies have spiracles on their body and tracheae as respiratory organs.

Spiders are not insects. They have eight legs, and their bodies are divided in two parts, whereas all insects have six legs and three body parts. Spiders also have poison glands in their mouths that they use to kill or paralyze their victims.

Butterflies and Moths

Internal parasites thrive in the intestine of a cow's body. Parasites are organisms that live on other organisms and feed on them. Parasites can be internal as well as external. They can enter into the intestine by going through the mouth when these organisms are swallowed. They move into the intestine where they can reproduce. The environment of intestine facilitates parasite reproduction and growth. External parasites live on the skin, eyes and hairs and cause skin diseases, while internal parasites like worms affect stomach and intestine. 

This is a right option. Butterflies are insects.  A butterfly’s life cycle is made up of four parts, egg, larva (caterpillars), pupa and adult. Butterflies attach their eggs to leaves with a special glue. A larva or caterpillar hatches from each egg. Most caterpillars are plant eaters (herbivores). Fully grown caterpillars attach themselves to a suitable twig or leaf before shedding their outside layer of skin to reveal a hard skin underneath known as a pupa or chrysalis. Later on pupa convert in to butterfly. An adult butterfly will eventually emerge from the chrysalis where it will wait a few hours for its wings to fill with blood and dry, before flying for the first time. Butterflies can live in the adult stage from anywhere between a week and a year, depending on the species.

The part of the mosquito that looks like a big long nose is called it's proboscis. It is  part of the mosquito's mouth. Proboscis is a tubular feeding and sucking organ of certain insects like mosquitoes.They stick the long tubular organ in our body, and sucks the blood.

Leech belongs to phylum Annelida

Coconut crab has bronchostegal lungs for respiration. 

Spider and scorpion respire through book lungs.

Balanoglossus belongs to phylum Hemichordata, which has an excretory organ known as proboscis gland.

Scolex is the frontal segment of a tapeworm, having suckers or hooks for attaching to the host.

In some flatworms, the process of cephalisation includes the development in the head region of light-sensitive organs called ocelli or eye spots. For example, planaria.