Biology

Question 1

What is Urochordata also known as?

Answer 1

Urochordata is also known as tunicates because their body is surrounded by a leathery sheath composed of tunicin (cellulose).

Question 2

What type of feeders are Urochordata?

Answer 2

They are sessile and filter-feeders.

Question 3

What is retrogressive metamorphosis in Urochordata?

Answer 3

Retrogressive metamorphosis is when the notochord appears in the larval stage in the tail of the larva and disappears in the adult.

Question 4

What is the gut structure of Urochordata?

Answer 4

They have a U-shaped gut and a coelom is absent.

Question 5

What type of reproductive system do Urochordata have?

Answer 5

They are hermaphroditic.

Question 6

How does respiration occur in Urochordata?

Answer 6

Respiration occurs through gills.

Question 7

What type of circulatory system do Urochordata possess?

Answer 7

They have an incomplete closed circulatory system.

Question 8

What is the blood pigment in Urochordata?

Answer 8

Haemocyanin is the blood pigment.

Question 9

Do Urochordata have excretory organs?

Answer 9

The excretory organs are absent.

Question 10

How do Urochordata reproduce?

Answer 10

They reproduce asexually by budding.

Question 11

Give examples of Urochordata.

Answer 11

Examples include Herdmania and Selpa.

Question 12

What is the classification of Urochordata?

Answer 12

Urochordata is classified into three classes: Class I - Ascidiacea, Class II - Thaliacea, and Class III - Larvacea.

Question 13

What are the characteristics of Class I - Ascidiacea?

Answer 13

Class I - Ascidiacea includes sea squirts, has a notochord and post-anal tail found in the larval stage only, and consists of marine, solitary or colonial, sessile adults.

Question 14

What is the tunic composition in Class I - Ascidiacea?

Answer 14

The tunic is composed of an acellular matrix of tunicin.

Question 15

What openings do Class I - Ascidiacea have?

Answer 15

They have two openings: an inhalant and an exhalent siphon.

Question 16

What feeding method do Class I - Ascidiacea use?

Answer 16

They are filter feeders.

Question 17

What are the two orders of Class I - Ascidiacea?

Answer 17

The two orders are I) Enterogona and II) Pleurogona.

Question 18

What phylum were hemichordates formerly members of?

Answer 18

Hemichordates were formerly members of the phylum chordata.

Question 19

Why were hemichordates separated from chordates?

Answer 19

They were separated because they lacked a notochord.

Question 20

What structure in hemichordates resembles a notochord?

Answer 20

Their buccal diverticulum, which extends to the proboscis, resembles a notochord.

Question 21

What is the habitat and lifestyle of hemichordates?

Answer 21

Hemichordates are marine and solitary.

Question 22

What are the three body divisions of hemichordates?

Answer 22

The body is divided into proboscis, collar, and trunk.

Question 23

What type of symmetry do hemichordates exhibit?

Answer 23

Hemichordates are bilaterally symmetrical.

Question 24

What is the primitive notochord in hemichordates called?

Answer 24

The primitive notochord is restricted to the proboscis and is called stomochord.

Question 25

What type of tissue layers do hemichordates have?

Answer 25

Hemichordates are triploblastic.

Question 26

What type of body cavity do hemichordates possess?

Answer 26

Hemichordates have a true coelom.

Question 27

What is the shape of the gut in hemichordates?

Answer 27

They have a straight or U-shaped gut with an anus.

Question 28

What is the nature of the nervous system in hemichordates?

Answer 28

The nervous system is normally diffuse and variable.

Question 29

What type of circulatory system do hemichordates have?

Answer 29

Hemichordates have an open circulatory system.

Question 30

What is unique about the blood of hemichordates?

Answer 30

The blood has no color and corpuscles.

Question 31

What is the excretory organ in hemichordates?

Answer 31

The excretory organ is the glomerulus.

Question 32

What type of feeding do hemichordates practice?

Answer 32

Hemichordates are filter feeders.

Question 33

How many classes are there in Hemichordata?

Answer 33

There are four classes: Enteropneusta, Pterobranchia, Plantosphaeroidea, and Graptolita.

Question 34

Can you name examples of hemichordates?

Answer 34

Examples include Cephalodiscus and Rhabdopeura.

Question 35

What is the classification of Hemichordata?

Answer 35

Hemichordata is classified into four classes: Class I - Enteropneusta, Class II - Pterobranchia, Class III - Planctosoneroide, and Class IV - Graptolita.

Question 36

What are the general characters of Class I - Enteropneusta?

Answer 36

Class I - Enteropneusta (Acorn worms) has more than 70 species, is 2-2.5 m long, marine, solitary, and lives in shallow water. The body is divided into Proboscis, Collar, and Trunk.

Question 37

What are the key features of Enteropneusta?

Answer 37

Key features include well-developed gill slits, stomochord, a dorsal strand of nerve cells, sexual reproduction, living in burrows, and filter feeding.

Question 38

What is an example of a species in Class I - Enteropneusta?

Answer 38

An example is Balanoglossus.

Question 39

What are the general characters of Class II - Pterobranchia?

Answer 39

Class II - Pterobranchia includes tiny, deep-sea, colonial organisms with a modified proboscis into a shield and a short, sac-like trunk.

Question 40

What are the reproductive characteristics of Pterobranchia?

Answer 40

Asexual reproduction by budding is common in Pterobranchia.

Question 41

What are the body features of Pterobranchia?

Answer 41

Pterobranchia has one or no pharyngeal slits and the body is covered with protein collagen.

Question 42

What is the classification of Hemichordata?

Answer 42

Hemichordata is classified into four classes: Class I - Enteropneusta, Class II - Pterobranchia, Class III - Planctosoneroide, and Class IV - Graptolita.

Question 43

What are the general characters of Class I - Enteropneusta?

Answer 43

Class I - Enteropneusta (Acorn worms) has more than 70 species, is 2-2.5 m long, marine, solitary, and lives in shallow water. The body is divided into Proboscis, Collar, and Trunk.

Question 44

What are the key features of Enteropneusta?

Answer 44

Key features include well-developed gill slits, stomochord, a dorsal strand of nerve cells, sexual reproduction, living in burrows, and filter feeding.

Question 45

What is an example of a species in Class I - Enteropneusta?

Answer 45

An example is Balanoglossus.

Question 46

What are the general characters of Class II - Pterobranchia?

Answer 46

Class II - Pterobranchia includes tiny, deep-sea, colonial organisms with a modified proboscis into a shield and a short, sac-like trunk.

Question 47

What are the reproductive characteristics of Pterobranchia?

Answer 47

Asexual reproduction by budding is common in Pterobranchia.

Question 48

What are the body features of Pterobranchia?

Answer 48

Pterobranchia has one or no pharyngeal slits and the body is covered with protein collagen.

Question 49

• Larval body covered with

Question 50

branched ciliary bands

Question 51

• Elimentary canal 'L' shaped

Question 52

Tornaria Larva

Question 53

Class IV - Graptolita

Question 54

General Characters

Question 55

• Extinct class

Question 56

•Fossil graptolites (e.g.

Question 57

Dendrograptus) were

Question 58

abrrer in frdovirin and

Question 59

Silurian period.

Question 60

• Tubular chitinous skeleton

Question 61

• Colonial habits

Question 62

1

Question 63

2

Question 64

3

Question 65

4

Question 66

PHYLUM CHORDATA

Question 67

• Possess four major characteristics besides

Question 68

several other characteristics:

Question 69

Presence of Notochord

Question 70

Presence of dorsal hollow nerve cord

Question 71

Presence of post anal tail

Question 72

Presence of gill slits.

Question 73

What are the three subphyla of Phylum Chordata?

Answer 73

The three subphyla are Urochordata/Tunicata, Cephalochordata, and Vertebrata.

Question 74

What classes are included in the Subphylum Urochordata?

Answer 74

The classes are Ascidiacea, Thaliacea.

Question 75

What class is included in the Subphylum Cephalochordata?

Answer 75

The class is Leptocardii.

Question 76

What classes are included in the Subphylum Vertebrata?

Answer 76

The classes are Ostracodermi, Cyclostomata, Placodermi, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia.

Question 77

What is the classification group for lower chordates?

Answer 77

The classification group is Protochordata.

Question 78

What is the classification group for higher chordates?

Answer 78

The classification group is Euchordata.

Question 79

What is the significance of the Subphylum Hemichordata?

Answer 79

Subphylum Hemichordata is now considered to be an invertebrate group.

Question 80

What are the characteristics of Urochordata (Tunicata)?

Answer 80

They are the most primitive chordates, found in marine environments, sessile, and filter-feeders.

Question 81

Why are Urochordata also known as tunicates?

Answer 81

They are known as tunicates because their body is surrounded by a leathery sheath composed of tunicin (cellulose).

Question 82

What type of metamorphosis do Urochordata undergo?

Answer 82

They undergo retrogressive metamorphosis.

Question 83

What is the gut structure of Urochordata?

Answer 83

They have a U-shaped gut and an absent coelom.

Question 84

How do Urochordata reproduce?

Answer 84

They reproduce asexually by budding.

Question 85

What is the blood pigment in Urochordata?

Answer 85

Haemocyanin is the blood pigment.

Question 86

What type of circulatory system do Urochordata have?

Answer 86

They have an incomplete closed circulatory system.

Question 87

What are the respiratory structures in Urochordata?

Answer 87

Respiration occurs through gills.

Question 88

What is an example of Urochordata?

Answer 88

Examples include Herdmania and Selpa.