Hexapoda- Subgroup of Mandibulata Flashcards
What species is contained within Hexapoda ?
Insects
Describe the anterior section of an insect.
1 pair of antennae 1 pair of mandibles (near the mouth) 2 pairs of maxillae (palps) Sensory devices Ocelli- night vision device
Describe the general body plan of an insect
Head/ Thorax/ Abdomen
No appendages on Abdomen
Describe the Thorax
3 pairs of Uniramous limbs on the thorax
2 pairs of wings (ADULTS)
Why are wings important to insects ?
Enable locomotion
Forewing for flight, Hindwing for balance
Spreading of insect species across the globe
Used for displays (Butterflies)
Why are wings described as an APOMORPHY ?
New evolutionary development, not homologous with any existing appendages
How do insects prevent desiccation of offspring ?
Cuticle coat over eggs
What is the benefit of RESLIN to an insect ?
Elastic protein, Used to create elastic cuticle and for explosive jumping
What is the importance of the Exoskeleton ?
Provides a lightweight shell to which the muscles can attach
Made of chitin.
What is Apodeme ?
Ingrowths of the exoskeleton which provide attachment site for Connective tissue. Enables contraction and co-ordination.
What is the role of Sclerotin in cuticles ?
It is a component of cuticles, which acts as a form of tanning. Increasing the rigidity of the cuticle.
E.G Butterflies crumpled wings strengthen out of cocoon
Why do insects have 6 legs ?
Enables movement across any surface.
Triangle gait, always 3 legs on the floor- VERY STABLE.
What is a HEMIMETABOLOUS life cycle ?
There are similarities between the adult and the larvae
What is a HOLOMETABOLOUS life cycle ?
There are large differences between the adult and the larvae
Grub larvae, to Pupa and then to beetle
How to Insects respire ?
Use Tracheal system, Spiracle openings enable oxygen to enter In and carbon dioxide to be excreted using diffusion gradients.
