14. Insecta

Question 1

why are insects the most abundant and diverse group of animals on earth?

Answer 1

they have a simple yet highly adaptible body plan

Question 2

what are three benefits from being able to fly?

Answer 2

escape predators

find food

new habitats

Question 3

what are wings?

Answer 3

extentions of the cuticle and not true appendages

Question 4

what are the two hypothesis’s about insects wings?

Answer 4

1. wings first evolved as extensions of the cuticle that helped absorb heat but later modified for flight
2. wings allowed animals to glide from vegetation to the ground. also gills in aquatic insects

Question 5

describe three points about the head in the body plan of insects

Answer 5

one pair of antannae (crustaceans have two)

one pair of compound eyes (made of units called ommatidia)

ocellia pick up light in the eyes

Question 6

what appendages contribute to insects mouthparts?

Answer 6

one pair of mandibles (lower jaw)

one pair of maxillae (upper jaw)

the labium (floor of the mouth)

Question 7

what are the three segments in the thorax?

Answer 7

the posternum, mesosternum and metasternum

Question 8

what are insect wings made of? and what isspecial about them in terms of the circulatory system?

Answer 8

they are made of cuticle and the wings have veins that open into the body and contain haemolylyph (circulatrory blood)

Question 9

how many segments are in the abdomen of an insect and what are the three plates on the exoskeleton?

Answer 9

there are 9-11 segments and the plates are

tergum (doral - top)

sternum (ventral - bottom)

pleuron - (lateral on either side)

Question 10

how does the insects respitory system work?

Answer 10

each segment in the abdomen have spiracles. the spiracles open to a network of tracheae, tracheae branch to tracheoles, tracheoles brach to the cells

spiraclee > tracheae > tracheoles > cells

Question 11

what is the pharyx and what function does it have in the digestive system

Answer 11

to transfer food from the mouth to the oesophgus, similar to a throat.

Question 12

what is the function of the oesophagus and the crop?

Answer 12

the oesophagus is a tube to the mid gut that becomes inlarged into the crop to store food.

Question 13

when the food passes through the gizzard and proventriculus, what happens?

Answer 13

grind up food into smaller particles

Question 14

in the midgut, what does the gastric caeca do?

Answer 14

secretes enzymes to aid digestion

Question 15

what do the malpighian tubules do?

Answer 15

transport metabolic waste and food to the hind gut and out the body

Question 16

what does the hind gut do?

Answer 16

carries the undigested food to the rectum and anus