This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Chapter 1 BOOK-Arthropod- segmented creatures-insects and arthropods comprise 75+% of animals and over 60% of all living organisms-layers of the exoskeleton--cuticle (epicuticle, exocuticle, endocuticle)--epidermal cell layer--basement membrane-composition of exoskeleton = chitin (polysaccharide) + proteins-functions of the exoskeleton--protective barrier--water conservation in the wax layer covering the epicuticle--muscle attachment-exoskeleton shedding = molting-growth happens in stages = instars VIDEO LECTURES 1 and 2-Why study insects?--bugs are a part of where we have come from, what we are now, and where we will be in the future-insects excel at the numbers game-beetles are the largest species of insects…there are 368,000 kinds of beetles-insects do not have a backbone-chordata have backbones-more than ¾ of population on earth is insects and their close relatives-slide 9…chart of all living organisms on earth…plants, single celled organisms-don’t get hung up on the numbers-scientists disagree on the number of insects that there are on earth-excel at species and numbers-you would get too tired counting how many ants there are in a colony-an average bee colony has 50-60,000 inhabitants-1 queen, several hundred males, all the rest female worker bees-bees are the lower number in social insects-put 6.3 billion humans on a scale and weigh them and do the same with all the insects in the world…insects would weigh 6x more than human weight-insects have a great reproductive potential-many insects are born but don’t make it to the reproductive age-ecology- the study of life and its forms and their actions-the color of things that people is due to insects because they are pollinators-excelled at the numbers game…species and as individuals-6x biomass of humans and in reproductive potential-exoskeleton made of chitin…it is a bioprotein we don’t have in our body-need to know different layers and their functions-epidermis is living cells-insects do not have internal structures-muscles attach not to bones but to the basement membrane…innermost portion of exoskeleton-a hair coming through…can be sensory-EXOSKELETON FUNCTIONS--chemical/pathogen/UV ray protection--retard water loss/entry life is all about that water--physical protective barrier some have a tough exoskeleton there are soft bodied ones as well--muscle attachment internally--other- body color, hairs to keep from freezing, waste deposition…carry their waste around with them, can prevent them from being eaten-exoskeleton limitations--incremental growth…they go through stages of growth--limits ultimate size-their small size helps to make them successful-advantages of being small--getting away from predators, being able to hide--shorter time to maturity, reproductive potential--don’t need to eat as much--can fit into smaller places and find more resources-disadvantages of being small--takes longer to get from place to place--surface area to volume…talks about water inside...
View Full Document
This note was uploaded on 02/22/2012 for the course AG 2373 taught by Professor Staff during the Fall '10 term at Texas State.
- Fall '10