Module 6

Question 1

Specializations in Subphylum Vertebrata

Answer 1

Living endoskeleton, Functioning pharynx and efficient respiration, Advanced nervous system, Paired limbs.

Question 2

Craniation in Vertebrates

Answer 2

The formation of the head coordinates more complex movement and feeding behaviours.

Question 3

Hox Genes in Craniates

Answer 3

Craniates have two clusters of Hox genes; lancelets and tunicates have only one.

Question 4

Superclass Agnatha

Answer 4

Jawless fishes, lacking jaws, internal ossification, scales, and paired fins; with porelike gill openings and eel-like body plans.

Question 5

Class Myxini

Answer 5

Hagfishes are scavengers and predators with slime glands for predation escape and a cartilaginous skull.

Question 6

Class Cephalaspidomorphi

Answer 6

Lampreys have keratinised teeth, seven gill pairs, and a long larval stage called ammocoete.

Question 7

Superclass Gnathostomata

Answer 7

Jawed vertebrates with diverse body plans, locomotion, and habitats.

Question 8

Subclass Elasmobranchii - Sharks

Answer 8

Sharks detect bioelectric fields using Ampullae of Lorenzini and vibrations with a lateral line system.

Question 9

Subclass Elasmobranchii - Rays

Answer 9

Rays are dorsoventrally flattened with large pectoral fins fused with the head.

Question 10

Subclass Holocephali

Answer 10

Chimaeras with flat plate-like jaws and an upper jaw fused to the cranium.

Question 11

Class Osteichthyes

Answer 11

Bony fishes with endochondral bone, lungs or swim bladder, and a bony operculum covering the gills.

Question 12

Class Actinopterygii

Answer 12

Ray-finned fishes with fins supported by lepidotrichia, operculum for gill protection, and a swim bladder for buoyancy.

Question 13

Class Sarcopterygii

Answer 13

Lobe-finned fishes with cosmine scales and a vascularised swim bladder for respiration and buoyancy.

Question 14

Tetrapods Adaptations

Answer 14

Strong skeletal framework, lungs, paired nostrils, double circulation, and modified sensory receptors for land.

Question 15

Derived Characteristics of Amniotes

Answer 15

Amniotic egg with protective membranes: Amnion, Chorion, Yolk sac, Allantois.

Question 16

Class Amphibia

Answer 16

Tetrapods with smooth, moist skin, ectothermic, and forelimbs usually with four digits.

Question 17

Order Gymnophioda

Answer 17

Caecilians are burrowing or aquatic carnivores, often blind as adults.

Question 18

Order Caudata

Answer 18

Salamanders, some exhibit paedomorphosis, maintaining larval traits into adulthood.

Question 19

Order Anura

Answer 19

Frogs and toads with keratinised skin for protection against abrasion and water loss.

Question 20

Class Reptilia

Answer 20

Reptiles have a shelled amniotic egg, keratinised skin, powerful jaws, and internal fertilisation.

Question 21

Order Anapsida

Answer 21

Turtles and tortoises enclosed in shells with dorsal carapace and ventral plastron.

Question 22

Order Squamata

Answer 22

Lizards, snakes, and worm lizards.

Question 23

Order Crocodilia

Answer 23

Crocodiles and alligators with a secondary palate and a four-chambered heart.

Question 24

Class Aves

Answer 24

Birds evolved feathers for flight, hollow bones, specialised bills, are endothermic, and have a high metabolic rate.

Question 25

Class Mammalia

Answer 25

Mammals have mammary glands, hair, high metabolic rates, larger brains, and differentiated teeth.

Question 26

Order Primates

Answer 26

Primates have grasping hands, flat nails, fully opposable thumbs, and the species Homo sapiens evolved about 200,000 years ago.

Question 27

Evolutionary Specializations of Vertebrates

Answer 27

Living endoskeleton, Functioning pharynx and respiration, Advanced nervous system, Paired limbs.

Question 28

Craniation Significance

Answer 28

Formation of the head enables complex movement and feeding behaviours.

Question 29

Superclass Agnatha Features

Answer 29

Jawless, lack internal ossification, scales, paired fins; eel-like body with porelike gill openings.

Question 30

Class Myxini Key Traits

Answer 30

Hagfishes with slime glands for escape, cartilaginous skull, and sensory adaptations for poor eyesight.

Question 31

Class Cephalaspidomorphi Characteristics

Answer 31

Lampreys with keratinised teeth, seven gill pairs, and long larval stage called ammocoete.

Question 32

Chondrichthyes: Sharks

Answer 32

Bioelectric field detection via Ampullae of Lorenzini; mechanoreceptors in lateral line sense prey vibrations.

Question 33

Chondrichthyes: Rays

Answer 33

Dorsoventrally flattened body with fused pectoral fins; adaptations for bottom-dwelling.

Question 34

Class Osteichthyes Traits

Answer 34

Bony fishes with endochondral bone, swim bladder or lungs, and bony operculum covering gills.

Question 35

Subclass Actinopterygii

Answer 35

Ray-finned fishes with dermal rays in fins, operculum, and buoyancy swim bladder.

Question 36

Subclass Sarcopterygii

Answer 36

Lobe-finned fishes with cosmine-covered scales and vascularised swim bladder for respiration.

Question 37

Tetrapod Adaptations to Land

Answer 37

Strong skeletal structure, lungs, paired nostrils, double circulation, and sensory adaptations.

Question 38

Class Amphibia Traits

Answer 38

Ectothermic with smooth skin; forelimbs usually have four digits.

Question 39

Order Gymnophioda

Answer 39

Caecilians with small eyes; burrowing or aquatic carnivores.

Question 40

Order Caudata Traits

Answer 40

Salamanders with rudimentary limbs in some forms; some retain larval traits (paedomorphosis).

Question 41

Class Reptilia Characteristics

Answer 41

Keratinised skin, shelled amniotic egg, powerful jaw closure, and internal fertilisation.

Question 42

Order Anapsida Traits

Answer 42

Turtles and tortoises with rigid shells, dorsal carapace, and ventral plastron.

Question 43

Order Crocodilia Features

Answer 43

Crocodiles and alligators with four-chambered heart and secondary palate.

Question 44

Class Aves Characteristics

Answer 44

Feathers, hollow bones, specialised beaks, endothermic, and high metabolic rate for flight.

Question 45

Class Mammalia Features

Answer 45

Mammals with mammary glands, hair, larger brains, and differentiated teeth.