Unformatted text preview: Unit 5 - Maintenance and Movement
1. Describe embryonic origin of alimentary canal divisions.
2. Draw and label generalized alimentary canal and describe function of each
3. Draw and label generalized insect circulatory system and describe circulation pattern.
4. Describe the tracheal system of insects and define trachea, tracheoles, and taenidia.
5. Describe how insects maintain proper body temperature and how they keep from
Fill out the functions for the digestive structures.
mouth opens to preoral cavity which grinds and receives food as it ﬁ rst
enters the body pharynx
peritrophic membrane ileum
anus ﬁrst region of foregut heavily muscled for swallowing
swallows food and dumps it into crop secretes ﬂ uid to lubricate food as it passes out of pharynx & down esophagus
and into crop (also secretes some digestive enzyme) stores food while midgut enzymes (in some insects) enter through
proventriculus to digest the food acts as valve between crop and midgut. often contains
heavy teeth for further grinding of food
secretes digestive enzymes & peritrophic membrane. absorbs nutrients from
food broken down by digestive enzymes
ﬁngerlike pouches off midgut. known to house symbiotic bacteria ﬁlters harmful substances and nitrogenous waste from hemolymph
membrane secreted by midgut cells to protect cells of mid/hindgut. encloses
f ood but permeable to enzymes; digestive products removed and furtherdigestion
ﬁrst part of hindgut; larger than colon narrower portion of hindgut
posterior part of hindgut. dehydrates waste and compresses it into pellets expels compressed waste out of insects body Label Diagram 1 using your textbook as a guide.
crop ileum oesophagus rectum pharynx anus preoral cavity malpighian
tubule Alimentary canal embryonic origins
Which embryonic layer formed the midgut?
Which one formed the hindgut? peritrophic
membrane colon ectoderm ectoderm What happens to the foregut and hindgut lining when the insect molts?
they have a cuticular lining similar to exoskeleton- it sheds with exoskeleton What is the lining made of?
chitins and proteins Tracheal system
Why don't insects have lungs? air enters through spiracles What is the function of the tracheal system? getting air into their bodies
What is the function of spiracles? how much air is allowed into the insect body What is the function of taenidia? thickened bands around trachea, ﬂexible enough to bend but rigid to not collapse close
How does oxygen get to every cell in the insect body?
tracheloes (branches from trachea) gets within few cell diameters of each cell Circulatory system
Why is insect blood not red? lacks hemoglobin Does hemolymph transport oxygen to cells?
What is the insect heart?
Define ostia: no- carries nutrients, regulates ions, ﬁghts dz and heals wounds dorsal vessel tiny openings in abdominal region of vessel, control how much hemolymph enters the vessel Define aorta: remainder of the vessel minus ostia How does hemolymph move throughout the insect body? What direction does it flow?
pulsating organs (sit at base of antenna or wings and pump hemolymph into appendages)
ﬂ ows from body cavity -> organs -> wing veins How does hemolymph get into the wings and antenna?
Label the following circulatory system in diagram 2. Use your text for reference.
Diagram 2 1. aorta 10. 2. 11. wing circulation 3. dorsal vessel; heart 12. 4. ostia 13. 5. dorsal diaphragm heart 14. 6. ventral nerve cord 15. 7. ventral diaphragm 16. 8. septa dividing appendages 17. 9. brain Hemocyte nucleus 5.4 Maintaining body temperature
When an insect is at rest, what is its body temperature? ambient temperature What are some ways insects increase their body temperature? basking (posture and orientation), ﬂight What are some ways insects keep from freezing?
supercooling- remaining liquid at subzero temps without ice formation (evacuation of digestive system to
remove promoters of ice nucleation) Refer back to the unit objectives and see that you have met them.
GOOD LUCK ON EXAM 1! ...
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- Summer '08
- alimentary canal, body temperature, hemolymph, preoral cavity