Insect Phys Exam 1 - Quiz Questions

Front 1

Define in your own words the term "critical or transition temperature for water loss"

Back 1

Temp at which lipids in wax layer start to melt. Compromises integrity of cuticle, insects start to lose waterproofing wax layer. First discovered in roaches.

Front 2

What two main functions do cuticular lipids appear to have.

Back 2

Water balance, communication

Front 3

Explain how cuticular lipids maintain water balance

Back 3

Form waxy layer which mediates permeability of cuticle. Thicker lipid complex = higher water retention. Insects in low-humidity environments may have waxier epicuticle. At critical temp, lipids begin to melt and have higher rate of water loss.

Front 4

Explain how cuticular lipids play a role in communication

Back 4

Cuticular lipids (hydrocarbons) can act as pheromones or chemical signals. In social insects, caste is regulated by these hydrocarbons.

Front 5

Why was it fortunate Ramsay chose to study Periplaneta americana's cuticle?

Back 5

Its cuticle has number of aldehydes and fatty acids along with hydrocarbons. These covered water droplets, which would have not happened in other insects. This led him to to further look into what part of the cuticle was responsible for water transpiration.

Front 6

According to May, Digby coined the term Temperature Excess. In your own words, what
is the definition of this term?

Back 6

Difference in air temp and insect's body temp. Is the change in body temp and surrounding air temp.

Front 7

Actinometer measures what?

Back 7

Radiation

Front 8

Thermocouple measures what?

Back 8

Temp

Front 9

Pyrheliometer measures what?

Back 9

Radiation

Front 10

Anometer measures what?

Back 10

wind speed

Front 11

According to Digby what variable does NOT have an effect on the temperature excess of
a small physical body, but was later proven to result in higher temperature excess?

Back 11

hairs covering body

Front 12

Howard E. Hinton contributed to the war effort in which way?

Back 12

Conducted research on stored food pests which damage rations and supplies. Described common pests, descriptions, and habits to help military with pest control

Front 13

Hinton wrote the following "In order to avoid circumlocution the term [……. ] is
proposed to designate the phase of an instar which is enclosed within the cuticle of the
previous instar." What was the term he proposed in 1946?

Back 13

Pharate

Front 14

What new term did Hinton propose in a 1966 Nature paper (from the Greek word for
"loosening a bandage").

Back 14

Apolysis

Front 15

This is a picture of Wigglesworth's favorite research insect. What is this insect and tell
me little about why it such an important and interesting study animal for insect
physiology. Cover at a minimum the following in your answer: feeding and molting
habits; research techniques that can be used (and not when studying, say, vertebrates),
cuticular markers.

Back 15

Rhodnius prolixus (kissing bug). Moulting induced by activation of stretch receptors after blood meal allows researcher to control timing of moults. External cuticular patterning allows easy visual examination of epidermal cell determination during and between moults. Relatively large and easy to rear. Compatible with surgical manipulations such as parabiosis

Front 16

Explain in your own words what this figure shows and what it means

Back 16

Wigglesworth cauterized area with dotted lines, darker spots show pigment cells on nymph. B shows growth in pigmented area after moulting and burn healing. This shows cells grew/divided to heal the wound. Since growth of pigmented area remained after moult, shows pigmented cells had been pre-determined to be pigment cells.

Front 17

Moulting hormone modern name

Back 17

Ecdysone

Front 18

Inhibitory hormone modern name

Back 18

JH

Front 19

Where is PTTh synthesized and released?

Back 19

Synthesized in 2 pairs of neurosecretory cells in brain. Released from either CC or CA.

Front 20

Where is ecdysone synthesized and released?

Back 20

Synthesized and released from PG

Front 21

Where is JH produced and released?

Back 21

Synthesized and released from CA

Front 22

In Manduca'sexta what behavior does NOT signal the onset of metamorphosis?

Back 22

Climbing

Front 23

Define in your own words either the term "Gate" or the term "Gating" I as it pertains
to Insect Physiology and this week's readings.

Back 23

An event which provides a gene expression switch restricting a process to certain window of time. Gate needs to be opened by specific condition before physiological process can take place. In this case, circadian gating means metamorphosis will only take place in a specific window of time.

Front 24

Regarding the Nijhout and Williams paper:
Explain, in your own words, why Fig. 6 is (more) informative than Fig. 5. Why are
both figures printed in the paper despite the fact that they use the same data points.

Back 24

5 shows growth curves for lavae in borderline state for few days before PTTH release but doesn't correct for how long larvae had already been in instar. 6 arranges curves so PTTH curves coincide in time. Shows that all curves intersect within narrow window for time and weight (~5g)

Front 25

When a M. sexta larva weighing less than 5 g is starved then PTTH release is delayed. T or F?

Back 25

True

Front 26

After crit weight is attained the M. sexta brain is only competent to release PTTH if JH is present at high titres. T or F?

Back 26

False

Front 27

What is a kymograph? Why did Truman use it in the paper?

Back 27

Device that measures change in position over time. Allowed him to detect subtle larvae movement and showed him when movement occurred.

Front 28

How does circadian gating of synchronous L > L ecdysis differ from circadian gatin of P > A eclosion?

Back 28

L > L gated by PTTG release rather than circadian gating of ecydsis itself. Eclosion, moult takes period of weeks (need to synthesize new organs, etc.) and only afterward is there endocrine signal for ecdysis. P > A Ecdysis also occurs within shorter period than 1-2 days for L > L.

Front 29

Why is M. sexta such a good "lab rat" compared to Antheraea pernyi?

Back 29

Can eat prepared diet instead of fresh leaves, large and easy to manipulate/visualize

Front 30

What were Betenandt's main contributions to insect phys?

Back 30

Isolation of ecdysone and bombykol

Front 31

Which statements about "paper factor" are true?

Back 31

Inspired new era of pest control, co-discovered by Slama and Williams, now called juvabione