1. Name and describe five classes of arthropods.
2. Insects – Insects are hexapods and are regarded as the biggest group in the arthropod phylum.
3. Centipedes – Centipedes are arthropods which belong to the Chilopoda class of Myriapoda subphylum. Centipedes are metameric beings which with a single pair of legs in every section of the body.

• Millipedes – millipedes are invertebrates which have bodies that are elongated and have numerous sections, many of which have two pairs of legs.

1. Arachnids – arachnids are invertebrate animals that are joint-legged and belong to the Chelicerata subphylum.
2. Crustaceans – crustaceans include the largest arthropod taxons such as lobsters, crayfish, woodlice and krill.
3. Describe the exoskeleton in arthropods. What is it made of? What is/are its functions?

The exoskeleton is a flexible, tough integument that covers most arthropods (Michels, Appel & Gorb 2016). The exoskeleton is made of thickened areas where the chitin is stiffened or strengthened by substances including hardened proteins and minerals. The function of the exoskeleton is to protect and support the creature’s body in comparison to the internal skeleton in human beings.

3. What is ecdysis? Why does this process occur?

Ecdysis is the procedure where a creature regularly sheds off one part of its body, usually the covering on its exterior layer, during certain times of the year (Rutland, Cigler & Kubale, 2019). Ecdysis occurs because the skeleton of an arthropod is usually inflexible and therefore to grow bigger, arthropods have to shed off the exterior layer.

4. What is an appendage? Describe the appendage adaptations within the Arthropoda phylum.

Appendages are highly complicated structures that consist of many tissues that can individually regenerate. The appendage contains three sections which have jointed appendages and hard exoskeletons. They are also adapted to survive on land with book lungs for breathing and a trachea.

5. Besides waste removal, what are the other functions of Malpighian tubules?

The Malpighian tubules also emit liquids within the posterior intestine whereby they are later reabsorbed, and particular materials are moved to the hemolymph.

6. On which segments of the crustacean body do legs attach?

The legs in crustaceans are attached in the thorax and the head.

7. What is the difference between uniramous and biramous appendage?

The uniramous appendage contains a single sequence of sections that are connected end-to-end. Biramous limbs are divided into two parts, and every branch includes sections of series that are attached end-to-end.

8. Describe how centipedes and millipedes differ from each other.

Millipedes have two pairs of legs in every segment of their bodies while centipedes have one.

9. What are the two different types of metamorphosis? How do they differ?

The two diverse types of metamorphosis are incomplete and complete metamorphosis whereby the body of insects changes during the lifecycle procedure. The main difference between the two is that complete metamorphosis contains ravenous, active, consuming larva, and a pupa that is inactive while incomplete metamorphosis contains a nymph which looks like a small adult.

10. What are the advantages of the exoskeleton?

Exoskeleton offers an outer layer that is strong and is considered as a shield against environmental dangers and predators (Zhang et al. 2019).

11. What occurs during ecydysis?

Ecdysis is the procedure where a creature regularly sheds off one part of its body, usually the covering on its exterior layer, during certain times of the year.

12. What controls this process?

Ecdysis occurs because the skeleton of an arthropod is usually inflexible and therefore to grow bigger, arthropods have to shed off the exterior layer.

13. What type of circulation system do arthropods have?

Arthropods have an open circulatory structure with hemolymph and an analog of blood circulatory system.

14. What stage is missing in simple metamorphosis?

The pupa stage is regarded as the missing stage in simple metamorphosis.

15. In insects that undergo complete metamorphosis, the larvae and the adults occupy different habitats. Why is this beneficial to the environment?

The larvae and adults live in diverse habitats to enable them to successfully adapt to the changes in the environment which is beneficial because they use various resources of food.

16. What is the benefit of wings to an insect?

Wings are helpful to insects because they help them in dispersal, getting a mate and avoiding predators (Lin & Lavine, 2018). Wings further assist insects in producing sound, protection, visual communication, and heat orientation.

17. Describe the functions of an animal’s nervous system.

In animals, the nervous system is used to transmit and process information thus directing the animal’s response.

18. How does a depressant impact the nervous system function?

Depressants increase the action of the GABA (gamma-aminobutyric acid) thus inhibiting brain activity.

19. Why are daphnia used in this study?

Daphnia is the best organisms to use in biological studies because they are responsive to alterations in the chemistry of water and are simple to raise in aquariums.

20. How does the heart rate relate to the impacts that depressants and stimulants have on the nervous system?

Depressants are fundamentally used in slowing down the different body processes. The effect of depressants on the nervous system is that they reduce the blood pressure, breathing, brain activity, and heart rate.

References

Lin, X., & Lavine, L. C. (2018). Endocrine regulation of dispersal polymorphism in winged insects: a short review. Current opinion in insect science, 25, 20-24.

Michels, J., Appel, E., & Gorb, S. N. (2016). Functional diversity of resilin in Arthropoda. Beilstein journal of nanotechnology, 7(1), 1241-1259.

Rutland, C. S., Cigler, P., & Kubale, V. (2019). Reptilian Skin and It’s Special Histological Structures. In Veterinary Anatomy and Physiology. IntechOpen.

Zhang, M., Jiao, D., Tan, G., Zhang, J., Wang, S., Wang, J., … & Ritchie, R. O. (2019). Strong, Fracture-Resistant Biomimetic Silicon Carbide Composites with Laminated Interwoven Nano-Architectures Inspired by the Crustacean Exoskeleton. ACS Applied NanoMaterials.