reptiles

Question 1

ectothermic

Answer 1

environment regulates body temp

Question 2

preferred optimum temperature zone

Answer 2

range of temperatures required to allow thermoregulation

Question 3

preferred body temperature

Answer 3

optimum temp for body functions

Question 4

behavioural fever

Answer 4

seek out higher than normal temperatures when sick/stressed

Question 5

humidity

Answer 5

50-70%

Question 6

lighting

Answer 6

12-14 hours of light/day
UVA light = 320-400nm - stimulates reproductive behaviour in lizards
UVB - 290-320nm = required for conversion of vit D3 in skin, important for calcium metabolism

Question 7

diet

Answer 7

Ca:P = 2:1
feeding frequency depends on weight gain/condition

Question 8

basic features

Answer 8

vertebrates
heavily keratinised skin
ectothermic
internal fertilization (most egg laying)
nucleated red blood cells

Question 9

what is thermoregulation controlled by

Answer 9

hypothalamus

Question 10

2 main mechanisms of acquiring heat

Answer 10

heliothermy - sun
thigomothermy - warm object

Question 11

CV system thermoregulation

Answer 11

heart rate and vasodilation/vasoconstriction
high temp - HR and vasodilation increases - warm blood to periphery
low temp - HR and vasodilation = warm blood retained in core
lungs can be bypassed by means of a right to left shunt, meaning reduced heat loss by evaporation

Question 12

behavioural thermoregulation

Answer 12

body position and shape
burrowing/hiding/shade seeking
pigmentation

Question 13

metabolism

Answer 13

slower than in mammals
15-20% at 37 degrees
dependent on activity, diet, size, body temp
reptiles utilise mainly aerobic metabolism but will switch to anaerobic for periods of intense activity
consequence = build up of lactic acid, drop in blood pH and reduced affinity for oxygen in haemoglobin

Question 14

light dependency

Answer 14

for physiological functions
natural sunlight provides optimum full spectrum
UVA 320-400nm required for normal feeding behaviour, reproductive activity etc
UVB 290-320nm required for conversion of sunlight to vitamin D3

Question 15

skeleton features

Answer 15

flexible spine
number of vertebrae variable
ribs well developed
movement of head occurs mainly at occipital condyle
99% of calcium stored in bones

Question 16

what conditions can develop if calcium metabolism is altered or dietary supply is insufficient?

Answer 16

metabolic bone disease
hypoglycaemia

Question 17

bone features

Answer 17

lack the haversian bone systems
bone healing is slow

Question 18

skeletal growth

Answer 18

epiphyseal growth plates do not close - no skeletal maturity occurs

Question 19

skull features

Answer 19

2 skull types; diapsid and anapsid

Question 20

integument features

Answer 20

waterproof
shed periodically to allow growth
3 layers;
stratum corneum
intermediate layer
stratum germinativum (stratum basale)

Question 21

ecdysis

Answer 21

shedding of old skin
controlled by thyroid gland

Question 22

dysedysis

Answer 22

failure to shed
usually husbandry related

Question 23

CV system features

Answer 23

blood volume = 8-10% bw
3 chambered heart
mixing of oxygenated and deoxygenated blood occurs but kept to a minimum

Question 24

portal systems

Answer 24

• renal portal system
  external iliac veins - carry blood draining from hind limbs = enter large renal portal vein
  means some of blood returning from hindlimbs enters kidney before returning to circulation
• hepatic portal system

Question 25

respiratory system

Answer 25

larynx easily identifiable
trachea leads to paired lungs
no diaphragm
lung is simple sac structure - reticular pattern of ridges increases surface area for gas exchange

Question 26

phases to respiration

Answer 26

expiration
inhalation
rest phase
temperature controlling factor

Question 27

GI system

Answer 27

oral cavity - mucous secreting glands - moisten and lubricated food
teeth - only present in lizards and snakes

Question 28

dentition

Answer 28

enamel, dentine and cement - NO periodontal ligament
3 types of tooth:
- acrodont
-pleurodont
-thecodont

Question 29

polyphydonty

Answer 29

teeth continually replaced throughout life

Question 30

urinary system

Answer 30

excrete uric acid as the end product of protein catabolism
kidneys located in caudal coelomic cavity
no renal pelvis, no loop of henle, no renal pyramids
bladder present - except snaked
ureters open directly into cloaca

Question 31

egg laying types

Answer 31

oviparous
lay eggs which develop outside of body

viviaparous - eggs hatched internally

Question 32

which feature determines the sub-order a species is placed in?

Answer 32

anatomy of neck

Question 33

what are shells composed of

Answer 33

keratinised plates called scutes

Question 34

chelonia cardiorespiratory

Answer 34

nasal breathers
trachea short
no diaphragm
can switch to anaerobic respiration for long periods.
3 chambered heart + renal portal system

Question 35

chelonia blood sampling

Answer 35

jugular vein
dorsal coccygeal vein

Question 36

chelonoa GI

Answer 36

25% species completely herbivorous, rest omnivorous
no teeth, sharp beak instead
thick fleshy tongue
simple stomach, lies near bilobed liver
colon large and caecum distinct in herbivores
digestion slow = 2-4wks transmit time

Question 37

chelonia - urinary system

Answer 37

kidney has no loop of henle and no renal pelvis
urine can be excreted directly into urodeum or refluxed into either bladder or colon for further water conservation

Question 38

chelonia male reproductive system

Answer 38

single phallus which protrudes from the proctodeum =not involved in urination
concave plastron to assist with mounting
presence of phallus
longer distance from caudal edge of plastron to cloaca
longer broader tails than females
internal testes

Question 39

chelonia female reproductive tract

Answer 39

paired ovaries and oviducts
ova travel down reproductive tract and egg is formed
oviparous
females store sperm for a long time - up to 6 years
flat pastron, shorter distance between caudal carapace and cloaca

Question 40

lizards thermoregulation

Answer 40

colour change
body posture/position
behaviour

Question 41

lizards integument

Answer 41

integument heavily keratinised
skin waterproof
some species - spines/horns
skin heals slowly in reptiles
ecdysis occurs at regular intervals

Question 42

lizards skeleton

Answer 42

kinetic skill - allows wider gape
- pterygoideus and external adductor muscles main jaw closers + depressor mandible is main jaw opener
flexible spine

Question 43

cardiorespiratory lizards

Answer 43

large volume lungs
glottis closed except during inspiration and expiration
no diaphragm
rely on respiratory muscles - increase chance of lung infection

Question 44

the 3 lung types found in lizards

Answer 44

unicameral
paucicameral
multicameral

Question 45

lizards GI

Answer 45

omnivores and insectivores - GI tract short and simple
herbivores - hindgut fermenters

Question 46

urinary system lizards

Answer 46

lobulated kidneys
bladder
species with high potassium diets have salt glands which are additional route for excretion

Question 47

male reproductive system

Answer 47

abdominal testes
paired hemipenes
- stored in tail base
- only one used in each copulatory event
- not used in urination, often prolapse

Question 48

reproductive tract female lizards

Answer 48

paired ovaries and oviducts = long and pleated
mature oocytes that fail to ovulate remain in ovary

Question 49

sexing lizards

Answer 49

males =
larger, more colourful
presence of prominent dewlaps, crests and spines
have prominent femoral pores on thigh areas

Question 50

snakes thermoregulation

Answer 50

based on behaviour
basking used to gain heat, coiling to retain

Question 51

snake integument

Answer 51

scales joined by small folded areas of skin
pigment in subdermal layers
ecdysis important to allow growth