ZOO201 Subjective 2022

Zoo201 final term subjective · Fall 2022 by · MUHAMMAD HABIB · *Garden centrepeds*

• Members of the class Symphyla (sim-filah) (Gr. Sym, same phyllos, leaf) are small arthropods (2 to 10 mm in length) that occupy soil and leaf mold, superficially resemble centipedes, and are often

Called garden centipedes.

*Do insect have memory*

• Research has demonstrated that insects are capable of some learning and have a memory.
• For example, bees (order Hymenoptera) instinctively recognize flowerlike objects by their shape and ability to absorb ultraviolet light, which makes the center of the flower appear dark.

*Mating behavior of insects*

• Most insects have complex mating behaviors for locating and recognizing a potential mate, for positioning a mate for copulation, or for pacifying an aggressive mate.
• Mating behavior may involve pheromones (moths, order Lepidoptera), visual signals (fireflies,

Order Coleoptera), and auditory signals (cicadas, order Homoptera; and grasshoppers, crickets, and katydids, order Orthoptera)

• Once other stimuli have brought the male and female together, tactile stimuli from the antennae and other appendages help position the insects for mating.
• Mating behavior starts by locating mates.
• Male and female have different strategies toward copulation and reproduction.
• After locating mates is courtship; one male and female have encountered each other, they may

Proceed directly to copulation or may first engage in various rituals, collectively known as Courtship. • The final ritual is copulation.

*Nervous system of star fish*

• The nervous system of sea stars consists of a nerve ring that encircles the mouth and radial nerves That extend into each arm.
• Radial nerves lie within the ambulacral groove, just

Oral to the radial canal of the water-vascular system And the radial strands of the hemal system.

• Radial nerves coordinate the functions of tube feet.
• Other nervous elements are in the form of a nerve net associated with the body wall.
• The nervous system of the starfish is very simple,

There is no brain and there are not even any ganglia To coordinate movement.

*Ectotherms*

• Many insects are ectotherms (animals in which their heat source is primarily from the

*Hetrotherms*

• Heterothermy (“hetero”, different) occurs in animals which are able to switch from endothermy to ectothermy.

*Sea star phylum*

Phylum echinodermata.

*Aristotle lanterns in econoids*

• A chewing apparatus, called Aristotle’s lantern, can be projected from the mouth.
• It consists of about 35 ossicles and attached muscles and cuts food into small pieces for ingestion.
• The mouth cavity leads to a pharynx, an esophagus, and a long, coiled intestine that ends aborally at the anus.
• The teeth of Aristotle’s lantern are typically extruded to scrape algae and other food from rocks, and some urchins can excavate hiding places in coral or rock even in steel.

Skeleton of sea urchin

Sea urchins (Echinoidea) have the most developed skeleton, consisting of heavy test (shell) and spines. The common feature of such skeletons is a calcite crystals immersed in dermis and covered with epidermis [3,4]. Besides mineral component, spines contain glycoproteins, providing them some mechanical flexibility

Complete metamorphosis

is the type of insect development that includes egg, larva, pupal, and adult stages, which differ greatly in morphology. The lifecycle of butterflies, ants, fleas, bees, beetles, moths, and wasps are examples of the complete metamorphosis.

Mutualism and parasitism

Mutualism is a symbiotic interaction in which both species benefit from the relationship. But, parasitism is another type of symbiotic interaction in which the parasite benefits on the expenses of the host. Both species are involved in the interaction live in the same habitat