Amphibians

Question 1

Give the species found within the class amphibian.

Answer 1

Caecilians
Salamanders/ Newts
Frogs/ Toads

Question 2

Give the phylogeny of caecilians

Answer 2

In the class amphibian
In the order Apoda 

Also found In the clade Gymnophiona

Question 3

Give the meaning of Apoda and Gymnophiona

Answer 3

Apoda- Without legs

Gymnophiona- Naked

Question 4

Do caecilians have limbs or limb girdles ?

Answer 4

Neither, have lost them due to their lifestyle of burrowing

Question 5

Give morphological adaptions of caecilians to burrowing.

Answer 5

Highly ossified and compact skull.

Small eyes, coverable by skin.

Question 6

How large are caecilians ?

Answer 6

5 cm to 150cm

Question 7

Describe the caecilian body,

Answer 7

Elongate
Segmented by annular grooves
Some have scales

Question 8

caecilians have a reduced lung, give the species which shares this characteristic through convergent evolution.

Answer 8

Snakes

Question 9

Give the habitat of caecilians

Answer 9

Moist forest soil, tropical conditions

Question 10

What is the diet of caecilians ?

Answer 10

They are carnivorous.

Grip prey and twist it to process it,

Question 11

Give the life cycle of most Caecilians

Answer 11

OVIPAROUS- lay eggs

Can be terrestrial or aquatic

Question 12

Some caecilians are VIVIPAROUS, What does this mean ?

Answer 12

Give birth to live young,

Question 13

How do viviparous caecilian offspring gain nutrients ?

Answer 13

Larvae have teeth to scrape epithelial lining of oviduct to gain nutrients secreted by oviducal cells.

Question 14

Matrotrophy can occur in caecilians. What does this mean ?

Answer 14

Mother cares for the offspring.

Question 15

Give the habitats of newts and salamanders.

Answer 15

Cooler, northern temperate regions.
Few tropical and subtropical species
Some entirely aquatic, others terrestrial

Question 16

Give the key defining features of Newts and salamanders

Answer 16

A Tail

Equal length limbs- bend body as walk.

Question 17

Describe the basic reproductive cycle of N&S

Answer 17

Eggs are laid in water
Larvae hatch as tadpoles
Metamorphose into adult

Question 18

What is Paedomorphis ?

Answer 18

The retention of larval features when the organism reaches maturity.

Question 19

Give an example of a species which shows this Paedomorphis.

Answer 19

Mole Salamanders.
Can remain in aquatic larval from throughout life, Retaining gills
Never progress to terrestrial adults
Dictated by environmental conditions in larval stage

Question 20

Fertilisation in newts and salamaders is mainly….

Describe the fertilisation process.

Answer 20

Internal (external can occur)
No copulation
M produce gelatinous spermatophores, capped with sperm
Females pick up and store sperm with Cloaca.
Eggs are fertilised as they pass out the cloaca
Deposited in clumps

Question 21

Give the 3 native UK newt and salamander species.

Answer 21

Palmate
Smooth
Great crested

Question 22

Give the 3 invader species of salamanders and newts.

Answer 22

Fire Salamander
Alpine Newt
Italian crested Newt

Question 23

Give the order that Frogs and toads are found in,

Answer 23

Anura (meaning no tail)

Question 24

How are frogs and toad adapted for jumping ?

Answer 24

Have large hind limbs and webbed toes

Question 25

What are the dietary habits of frogs and toads ?

Answer 25

Foragers Wide variety of prey items Mainly carnivorous Will use large protusible sticky tongue.

Question 26

What communication is crucial in frog and toad breeding ?

Answer 26

Visual and auditory Will amass in aggregations Males, large vocal sacs to give mating calls

Question 27

Fertilisation in Frogs and toads is....

Answer 27

Mainly external

Question 28

Give the 3 different larvae life cycles of frogs and toads

Answer 28

Mostly Oviparous with Aquatic eggs and larvae Oviparous- Terrestrial eggs Viviparous- Oviviparity

Question 29

What is Lecithotrophy ?

Answer 29

The only nutrients supplied by the mother are those contained in the yolk.

Question 30

Give the 4 native UK species

Answer 30

Common Frog Common Toad Natter jack Toad Pool frog

Question 31

Non native species to the UK include the African clawed toad and American bullfrog. How many are there in total ?

Answer 31

9 Non native UK species

Question 32

Give the 2 environments in which frogs and toads are not present.

Answer 32

Arid environments | Extreme latitudes

Question 33

What is the global diversity of amphibians thought to be dependant on ?

Answer 33

The formation of the continents | Breaking up of land mass developed and restricted certain species

Question 34

Other than continent formation, how else did amphibians colonise land mass ?

Answer 34

Washed across the ocean on land rafts, created in freak storms

Question 35

A major peak in amphibian diversity occurred in the Cretaceaous, what can this be attributed to ?

Answer 35

The evolution and diversification of flowering plants

Question 36

Give the 3 causes of amphibian species reduction.

Answer 36

``` Reduced habitat (wide variety- hard to protect) Over Exploited (Eating them, trade increasing) Enigmatic decline (global warming, disease) ```

Question 37

What is enigmatic decline ?

Answer 37

Decline in a species even when a suitable habitat remains.

Question 38

Give the main cause of enigmatic decline in amphibians

Answer 38

Chytrid fungus

Question 39

What is the bacterium that causes the cytrid fungus.

Answer 39

B. Dendrobatdis | Has motile zoospores that swim in water, infected skin of amphibians

Question 40

How has global warming propagated the chytrid fungus ?

Answer 40

optimum growth is between 17-25 C | Increasing temperatures make certain habitats able to support the fungus.

Question 41

What are the symptoms of the chytrid disease?

Answer 41

Sloughing of skin Paralysis of hind legs Sufferers will die.

Question 42

How do non native UK species influence the disease spread ?

Answer 42

Pest species are resistant, able to pass on the disease without suffering themselves

Question 43

How quickly is the chytrid disease spreading per year ?

Answer 43

20-100 km per year.