Download 1 pair legs/segment

JOURNAL
KWL: What do you know about insects?
What do you want to know? What have you
learned? (at end)
SUBPHYLUM
UNIRAMIA
Class Chilopoda
centipedes
Class Diplopoda
millipedes
1. 1 pair legs/segment
1. 2 pairs legs/segment
2. About 15 body segments
2. 11-100 body segments
3. Flat bodies
3. round bodies
4. Habitat- moist areas
4. moist areas
5. Diet- carnivores
5. herbivores
6. Defense-
6. Defense-
a. Venomous maxilliped
a. Roll into a ball
b. Bite feels like wasp sting
b. Produce hydrogen
cyanide- repellant
Class Hexapoda- insects
1. Three body regions
a. Head
b. Thorax
c. Abdomen
2. One pair antennae
3. Six legs
4. Digestion/Feeding
a. Different mouthparts
reduces food
competition among
different species.
b. Chewing- mandibles
(grasshopper & most
beetles)
c. Siphoning- tube for sucking (butterfly)
d.
Piercing &
sucking- cut
thru skin or
plants (mosquito,
assassin bug)
e. Sponging- absorbing food (fly)
5. Circulation- open
a. Not used in gas exchange
b. Distributes nutrients, hormones,
pheromones.
6. Thermoregulation- ectothermic
a. Bodies must warm up before able
to fly.
7. Excretion
a. Malpighian tubules- dump wastes
into intestine.
b. Waste- uric acid crystals to
prevent water loss.
8. Nervous & Sensory System
a. Compound eyes
1. Some images
2. Color (UV light)
3. Shape
4. Movement
b. Some have simple
eyes- ocelli
What an insect
is looking at…
What it actually
sees…
Compound eye
under the
microscope.
c. Some can detect odors- flies, bees
d. Tympanic membrane-
1. detect sound
2. Located on legs or abdomen
e. Setae- hairs on legs, body, antennae
1. Movement
2. vibrations
setae
9. Respiration
a. Spiracles- holes in body thru which
air enters
b. Tracheal tubes- extend length of
body for distribution & exchange of
gases.
spiracles
10.Reproduction
a. Dioecious
b. Controlled by:
1. Population density
2. Temperature
3. Seasons
4. Pheromones
5. Auditory signals
c. Females may use ovipositer to
deposit eggs in soil, tree, leaf, etc.
Elytraforwing
Hindwing
- flight
Beetles have hard
outer wing- elytrathat protects
membranous
hindwing- for flight
Journal
• Suppose a virus killed off all of the insects
on the planet. Predict how your life would
be different.
INTERESTING INSECTS
Many found around this school
female
male
Hercules beetles
Largest beetle in North America
Luna moth
In many areas they are endangered
due to air pollution.
Cicadas
Live
underground for
up to 17 years
Come out in
masses
Make the “summer” noise
http://www.cicadamania.co
m/audio/
Leave husk on
tree at final molt
“Cow Killers”- velvet ants;
Look furry w/red & black stripes
These are actually solitary female wasps
Have very painful sting!
Found all over Georgia
PHEROMONES
1. Sex- excite or attract opposite sex
2. Trailing- laid down by foraging insects
to help other members of colony find
food.
3. Alarm- warn others of danger (plants
do this as well)
4. Caste regulating- used by social
insects to control the development of
certain individuals in a colony.
SOCIAL INSECTS
EX: Ants, termites, most bees & wasps
1. Traits
a. Parental care of young
b. Several generations present
c. Division of labor
DIVISION OF LABOR
1. Reproductive caste
a. Queen1. produces eggs to maintain colony.
2. Regulates sex of offspringparthenogenesis
3. Unfertilized eggs- males
4. Fertilized eggs- females
Queen termite
b. Drones- mate with new queens
2. Worker caste
a. Sisters, all daughters of queen
b. Care for the eggs, larvae, queen & drones.
c. Forage for food
d. Maintain the nest
e. Take larvae to queen who feeds the larvae
“royal jelly”. This pheromone-laced liquid
determines the larvae’s role in the colony.
f. Future workers receive jelly for 1st 3 days.
g. Future queens receive jelly throughout larval
stage.
h. Soldiers- defend the nest
** Bees & wasps do not have
soldier insects.**
Solitary Insects
Advantage 1. Hide from
predators
s
2.
3.
4.
No immediate
competition
Live in small
spaces
Exploit small
food resources
Disadvant 1. Lack of social
ages
benefits
Social Insects
1. Group defense &
alarm
2. Food gathering
3. Nest building
4. Care of young
1. Intense predation
2. Parasitism
3. disease
ANT SLAVERYSome ant species invade others nest & steal
larvae. They take them back to the nest
where they become workers.
ANT FARMINGSome will “herd” aphids & protect them from
predators. Aphids supply sweet liquid- honey
dew which ants eat.
INSECT METAMORPHOSIS
Paurometabolus- incomplete
1. Egg
2. Nymph- look like small
adults
a. Lack reproductive
organs
b. Lack wings
3. Adults- after several molts,
reproductive organs &
wings are grown.
Holometabolus- complete
1. Egg
2. Larvae- wormlike (grubs- beetle
larvae)
a. No reproductive organs
b. No wings
c. Must eat constantly to store
enough energy for pupa stage
3. Pupa- inactive stage
a. May be surrounded by cocoon
(moths).
b. Body is undergoing
radical change.
4. Adult- emerges w/ reproductive
organs & wings.
ECONOMIC/ENVIRONMENTAL SIGNIFICANCE
BENEFICIAL
HARMFUL
Provide products
EX: wax, honey, silk
Parasites (fleas, lice)
Pollinate 65% of all plant
species (food crops)
Control harmful insect
population (praying mantis)
Vectors for disease (fleas
spread bubonic plague)
Destroy $5 billion in crops
annually
Medicinal purposes (bee venom
for M.S. and maggots for
sores that won’t heal.)
Some people are allergic
(bees)
Can cause death
Soil insects aerate the soil &
decompose
Provide food source for many
cultures
1. The reproductive males in a social insect colony are
called?
a. Drones
b. Workers
c. nymphs
2. Immature insects lack reproductive organs & ___.
a.
Mouths
b. Wings
c. Respiratory organs
Use the diagrams below to answer questions 3-5.
3. Which organism is the nymph?
4. Which organism is the pupa?
5. Which of these is holometabolous metamorphosis?
C
A
D
B
E