Arthropoda

• what does "arthro" mean?

  joint
• what does "poda" mean?

  feet
• how many species are there in the phylum arthropoda?

  more than one million
• what kind of symmetry does the phylum arthropoda see?

  bilateral
• why do arthropods have exoskeletons?

  to protect from the environment and help to conserve water in the body in environments with a lack of water
• what is the exoskeleton segregated by?

  the epidermis
• what does the epidermis consist of?

  chitin and proteins
• what are the limitations of a hard exoskeleton?

  limits growth as needs to be shed in order to grow, limits gas exchange, limits movement
• what is the growing process in arthropods called?

  moulting
• what produces the exoskeleton?

  the epidermis
• what is the growing process called?

  moulting
• how many times may they have to shed during the growing process in order to become full sized adults?

  three or four
• what are the four ways in which arthropods can undergo gas exchange?

  through the skin, gills, book lungs or tracheae
• what kind of arthropods are able to undergo gas exchange through the skin?

  very small ones
• what kind of arthropods are specialised for gas exchange by having gills?

  aquatic organisms
• what kind of arthropods are specialised for gas exchange by having book lungs?

  terrestrial ones such as scorpions and spiders
• what are book lungs?

  a laminated cavity which acts like a lung so that oxygen can be transmitted into the blood stream
• what is it like inside the cavity of a book lung?

  humid
• what kind of arthropods are specialised for gas exchange by having tracheae?

  terrestrial organisms such as insects and millipedes
• what are the three sensorial organs in arthropods?

  mechanoreceptors, chemoreceptors and photoreceptors
• how many subphylum of arthropods are there?

  six
• what kind of symmetry do arthropods display?

  bilateral
• what type of cavities do arthropods have?

  coelomates
• what is sexual reproduction like for arthropods?

  sexual reproduction with separate sexes and sophisticated complex mating rituals
• what is the role of an exoskeleton?

  protects the organism from the environment and helps to conserve water in the body in environments with a lack there of
• what is the exoskeleton segregated by?

  the epidermis
• what is the exoskeleton produced by?

  the epidermis
• what happens when the hard cover is detached from the epidermis?

  the external part of the exoskeleton begins to be reabsorbed so that the animal does not lose that important resource
• what is metamorphosis?

  dramatic change in the form and habitats of an animal during its development after birth or hatching
• what are the three types of life cycle regarding metamorphosis?

  no metamorphosis, incomplete metamorphosis and complete metamorphosis
• what are hemimetabolous insects?

  insects with partial / incomplete metamorphosis = the insect has no pupal stage.
• what are the three stages in hemimetabolous insects?

  the egg, the nymph and the adult
• what is the pupal stage?

  when some insects undergo the transformation from immature to mature stage
• what do we call insects which do not go through the pupal stage?

  hemimetabolous insects
• what do we call insects which do go through the pupal stage?

  holometabolous insects
• what are homometabolous insects?

  insects which do go through the pupal stage