Tag: diversity in living world

Questions Related to diversity in living world

Hemichordata posses .......... for respiration.

  1. Lungs

  2. Gill slits

  3. Alveoli

  4. None of the above


Correct Option: B
Explanation:

Hemichordates consists of a small group of worm-like marine animals with an organ-system level of organization. They are nonchordates. The circulatory system is of open type. The blood flows to a cavity known as hemocoel which bathes the organs directly with oxygen and nutrients and there is no distinction between blood and interstitial fluid. They respire with help of gill slits.

So, the correct answer is option B

Which of the following is not a characteristic of hemichordates?

  1. They are widely distributed in shallow, marine and tropical waters

  2. They have epidermal nervous system

  3. Most of them have pharyngeal slits

  4. They have cylindrical body


Correct Option: D
Explanation:

Hemichordates may not always have a cylindrical body, cylindrical body is the main characteristics of nematodes. Rest all are the characteristics of hemichordates.

Protochordata shows radial symmetry and they are diploblastic.

  1. True

  2. False


Correct Option: B
Explanation:

Protochordates are basically non-vertebrate chordates. They are bilaterally symmetrical and triploblastic animals. They are coelomates and lack a cranium. They are also referred to as acraniates.

So, the correct answer is 'False'.

Multicellular organisms with pores are called

  1. Protozoans

  2. Poriferans

  3. Arthropodans

  4. Aves


Correct Option: B
Explanation:

Poriferans are commonly known as sponges. They are multicellular organisms with cellular level of organization. They are sessile and sedentary in nature. These have an exoskeleton made up of either spongin fibers or calcareous or siliceous spicules. The spicules form the skeleton of the body which provides protection. These spicules are  formed by sclerocyte cells present in the mesenchyme.

So, the correct answer is option B.

Which of the following is not a class of Hemichordata ?

  1. Pterobranchia

  2. Enteropneusta

  3. Planctosphaeroidea

  4. Ascidiacea


Correct Option: D
Explanation:

Ascidiacea is a class of subphylum urochordata. Rest all  pterobranchiaEg. Rhabdopleura; Enteropneusta Eg. Acorn worms (Balanoglossus, Saccoglossus);planctosphaeroidea Eg. Planctosphaertara pelagica are class of Hemichordata.

Find the odd example ______________.

  1. Sea lily

  2. Sea fan

  3. Sea cucumber

  4. Sea urchin


Correct Option: B

Paired appendages are not found in _____________.

  1. Hemichordates

  2. Urochordates

  3. Cephalochordates

  4. All of these


Correct Option: D

Which group of protochordates contains Balanoglossus?

  1. Urochordata

  2. Cephalochordata

  3. Tunicata

  4. Hemichordata


Correct Option: D
Explanation:

A) Urochordata is a subphylum of the phylum Chordata and is included in protochordata. It does not include Balanoglossus.

B) Cephalochordata is a subphylum of the phylum Chordata and is included in protochordata It does not include Balanoglossus.
C) Tunicata is another word for Urochordata.
D) Hemichordata is a phylum included in protochordata and includes Balanoglossus.
Hence, the correct answer is 'Hemichordata'.

In hemichordates, the dorsal nerve cord is

  1. Absent

  2. Present throughout

  3. Restricted to tongue region

  4. Restricted to collar region


Correct Option: D
Explanation:

In hemichordates and chordates nerve cord is dorsally placed.

A) Hemichordates have a nerve cord. It is not absent in them.

B) Nerve cord although dorsal, is not present in hemichordates throughout the body.
C) Nerve cord is not present in the tongue region.
D) The nerve cord is present only in the collar region of the body.
So the correct answer is 'Restricted to collar region'.

The body of Tongue Worm Balanoglossus is differentiated into

  1. Head, trunk and tail

  2. Trunk and tail

  3. Proboscis, collar and trunk

  4. Proboscis and collar


Correct Option: C
Explanation:

Tongue worm Balanoglossus is a Hemichordate. The basic character of Hemichordates is a division of the body into proboscis, collar, and trunk.

A) Head and tail are not present in Balanoglossus.
B) The tail is absent in Balanoglossus.
C) The body of Balanoglossus is divided into proboscis, collar, and trunk.
D) Besides proboscis and collar, a trunk is also present.
So, the correct answer is 'Proboscis, collar, and trunk'.