8 - Reptiles 2

Question 1

Important themes

Answer 1

Water conservation
Support and mobility on land against gravity
Dealing with temperature extremes and fluctuation

Question 2

Reptile temperatures

Answer 2

• ectotherms (similar body temp to environment)

- deal using behaviours

Question 3

Skin

Answer 3

• thick, dry, keratinized
• no respiratory function
• scales modified for different functions (ex: locomotion with traction for snakes)
• Epidermal layers shed through ecdysis

Question 4

Ecdysis

Answer 4

shedding skin

Question 5

Cryptic colouration

Answer 5

colour patterns resemble their surroundings

Question 6

Aposematic colouration

Answer 6

sharply contrasting or bright colours that advertise that animals are dangerous/distasteful to predators

Question 7

Mimicry

Answer 7

species resembles another species and gains protection from the resemblance

Question 8

Colour and colour change

Answer 8

Sex recognition and thermoregulation

Question 9

Thermoregulation

Answer 9

Lighter to reflect heat off and dark to absorb heat
Orient themselves the way needed to get more or less heat
Press body against warm surface
Blood flow to skin when they want to absorb heat
To avoid heat loss, blood flow in core of animal

Question 10

Support and movement

Answer 10

skeleton highly ossified (more support for terrestrial existence)
Additional cervical vertebrae (atlas and axis) for greater freedom of movement for the head

Question 11

Autotomy

Answer 11

tail loss
adaptation allowing lizards to escape from predator grasp
Caudal vertebrae of many lizards include vertical fracture plane to allow this
Lizard later regenerates lost portion of tail

Question 12

An exception to ectothermy

Answer 12

brooding indian pythons use metabolic heat to raise their temperature when incubating eggs
also dinosaurs were often mesothermic

Question 13

Behavioural thermoregulation

Answer 13

Orientation at right angles to sun’s rays
warming by conduction from warm surfaces
Cooling by seeking shade or burrows, assuming erect posture and nocturnal habits
Panting and blood flow directed to mouth

Question 14

Marine iguanas

Answer 14

Feed on algae in cold water

Bask in sun, flood flow to skin is increased to gain heat

Question 15

Hibernacula

Answer 15

snakes group up in one for the winter
provides thermoregulatory benefit
mass of bodies retain heat
good for temperate climates
important areas to protect

Question 16

Aestivation

Answer 16

some reptiles in warm dry climates

prolonged torpor/dormancy of an animal during a hot dry period

Question 17

Feeding

Answer 17

• most are carnivores other than some turtles/tortoises

Question 18

Tongue types

Answer 18

nonprotrusible (turtles/crocodilians)

protrusible (lizards and tuatara)

Question 19

Feeding adaptations of snakes

Answer 19

• bones of skull/upper jaw = moveable
• ligaments loosely join the halves anteriorly
• posterior pointing teeth
• glottis opens far forward in mouth s o snake can breathe while swallowing prey
• hinged maxillary bone in vipers
• venom glands in some (modified salivary glands)

Question 20

Snake venom

Answer 20

• some are neurotoxins that attach nerve centers and cause respiratory paralysis
• some are hemotoxins. break up blood cells and attack blood vessel linings

Question 21

Median/parietal eye

Answer 21

3rd eye/ pineal eye
sense light and darkness levels
plays role in circadian and cirannual rhythms
also used in orientation to the sun

Question 22

Pit organs

Answer 22

• heat sensitive organs on side of face in pit vipers like rattlesnakes
• used to detect objects with temperatures that are different than surroundings
• helps locate warm-blooded prey at night

Question 23

Magnetic compass sense

Answer 23

sea turtles and several other migratory species can detect earth’s magnetic field
particles of magnetite have been found in brains of species with the ability

Question 24

Parthenogenesis

Answer 24

Development of an embryo from an unfertilized egg cell. Females only

Question 25

Incubation temperature

Answer 25

in alligators and some lizards and turtles incubation temp determines sex of offspring